Holy-Terror-Manual-V6r5a.Pdf

VERSION 111611 Written & produced by the staff of

9167 Independence Ave. Chatsworth, CA 91311 (818) 998-7791 • FAX: (818) 998-7835 Skype: paul.patronete or patrick.selfridge www.MercuryMagnetics.com [email protected]

Circuitry design by Alan Cyr (www.Amp-Exchange.com)

If you do not know how to read a schematic, we strongly recommend that you take this project to a qualified technician for installation.

All Mercury Magnetics products are 100% handmade by us in California, USA. Copyright © 2006–2010 by Mercury Magnetics. All Rights Reserved. Mercury Magnetics, Mini-Choke, “Holy Terror,” “Holy Terror” Upgrade Kit, and “The Heart & Soul of Your Amp” slogan are trademarks of Mercury Magnetics. Axiom and ToneClone are registered trademarks of Mercury Magnetics. Orange Amps and Tiny Terror are trademarks of Orange Amps. Mercury Magnetics is not affiliated with Orange Amps. This project and its documentation is the result of technical investigations made by the engineering staff of Mercury Magnetics. The disclosure of the information herein may pertain to proprietary rights and the furnishing of these documents does not constitute an expresed or implied license to use such materials. Mercury Magnetics products are UL (Underwriters Laboratories Inc.) recognized components for the USA and Canada. OBJY2 component systems, electrical insulation, E120568. UL Recognition, class 130(b) – Class 200(n). OBJY8 component systems, electrical insulation, certified for Canada, class 130(b) – Class 200(n). Mercury Magnetics transformers and other products are in compliance with the European Union RoHS Directive 2020/95/EC with respect to the following substances: lead (Pb), mercury (Hg), cadmium (Cd, hexavalent chromium (CR (VI)), polybrominated biphenyls (PBB), and polybrominated diphenyl ethers (PBDE).

Attention: Modifying your Tiny Terror amp voids the Orange Amp warranty!

2 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

CAUTION! The voltages in your amplifier can be dangerous. Transformers and chokes are not user servicable parts. Installation of these components should always be performed by an experienced technician. The simple ability to use a soldering iron is not enough to qualify a “do-it-yourself person.” Those who are inexperienced in working with electronic circuits should never attempt to service their amplifiers. Household line currents can be deadly!! Transformers, chokes and large filter capacitors can store dangerous charges for several days, or longer, after the amplifier has been unplugged. Never touch the terminals of these components without being certain of their charge status. Risk of shock and damage to equipment may result from mishandling and/or improper use of these components. Please use common sense and always think safety first. After all, great tone is most enjoyed when you are alive to hear it.

SOLDERING NOTE: The Orange “Tiny Terror” is assembled using RoHS compliant, lead-free solder. Working with lead-free solder is different than standard solder. Generally a hotter iron is necessary. For more information we recommend doing a web-earch for “lead- free soldering techniques.” CAPACITOR DISCHARGE WARNING: Safe discharging of filter capacitors matters. It is essential for your safety and to prevent damage to the amp’s circuitry, that large or high voltage capacitors be fully discharged before measurements are made, soldering is attempted, or the circuitry is touched in any way. For information on how to do this, web-search “capacitor discharging.” Also see the appendix for additional information. CAPACITOR POLARITY: Note that many capacitors have positive and negative polarity, and are stamped accordingly. Be sure that their polarity is correct when soldering to a PCB. BRAIDING, TWISTING AND COILING LEADS: Do not braid, twist or coil the power transformer’s B+ lead wire. Check our reference illustrations and photos to see which leads are twisted together. Typically only the filament leads of the power transformer. Other posi- tioning of leads may be necessary to minimize amp noise. Follow are diagrams and instructs for optimal performance. TRIMMING TRANSFORMER LEADS: To minimize noise, measure and trim the solderable lead lengths of the transformers and Mini- Choke™. Route all wires cleaning around the tubes, chassis, etc. CLIPPING vs. UNSOLDERING PCB COMPONENTS: To make this Upgrade it will be necessary to remove several components from the Main PCB of the amp. Due to quality issues with modern off-shore PCB manufacturing, it can be difficult to unsolder an item without creating other problems, the most typical of which is an eyelet detaching from the PCB. Therefore we’ve indicated which components should be clipped vs. unsoldered. To unsolder heat your iron to 800ºF, then very quickly heating up one side of the existing solder connection while pulling it through on the other. If the iron is not hot enough, or you linger too long, the eyelet will get damaged (or fall off). If this happens you’ll have to fabricate a repair, or created a jumper to a trace. See this manual’s appendices for tips. POWERING UP A GUITAR AMP: After making any modifications to an amp’s circuit (e.g. this Upgrade) use a Variac along with an current meter (some have both) to slowly apply power to the amp while checking for warning signs of circuitry errors or shorts. See the section on “Using a Variac” at the end of this manual. LOADING OUTPUT TRANSFORMERS: You must connect a speaker or speaker cab to your amp before powering it up. Without a load the output transformer will blow. MINI-CHOKE FACTOID: A Mercury Mini-Choke™ replaces a resistor and adds a disernable amount of tonal dimension to the circuit. TRANSFORMER BREAK IN PERIOD: As a general rule, transformers require approximately 30 hours of playing time to be fully broken in. Please refer to Mercury’s website for more information. BE SAFE! ALWAYS USE PROTECTIVE EYEWEAR!

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 3

Mercury nameplate Mercury “Holy Terror” sticker CAPACITORS (silver mica)

680ρF .022µF “.022µF” capacitor may be marked ORP-TT-A ORO-TT 1x 2x as “223K” (power transformer) (output transformer)

RESISTORS (carbon film) CAPACITORS (electrolytic) 300KΩ 1/2W 1µF 1x (orange/black/yellow/gold) 1x 470KΩ 1/2W 2x (yellow/violet/yellow/gold) 4.7µF 2.2KΩ 1/2W 1x 1x (red/red/red/gold) 10µF 1.8KΩ 1/2W 1x Instructional CD ROM 1x (brown/grey/red/gold) 100KΩ 1/2W 10 F 2x (brown/black/yellow/gold) 1x µ 8x 2x 10KΩ 1/2W Note that many capacitors have +/- polarity. (brown/black/orange/gold) Be sure to study the schematics for the correct 8-32 size washers 330KΩ 1/2W directions when Upgrading your amp. 1x (orange/orange/yellow/gold) OTHER COMPONENTS ~12 in. double-poled, coils 1x double-throw Shielded RED, BLUE & YELLOW wire switch ~6 in. ~6 in.

insulation “spaghetti” Unshielded lament wire

Mercury guitar case sticker

4 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

Recommended tools for this project: • Good quality 25–35W solder iron • Drill & drill bits for making 1/4" & 7/16" holes in (capable of temps at ~800ºF) metal chassis • Electronics grade solder (60/40 rosen core) • Loctite 290 (green) • Solder sucker and/or wick • Pure isopropyl alcohol & Q-tips or electronic- • Set of screw drivers (Philips) grade contact cleaner • Small needle-nose plyers • Variac & current meter • Wire stripper & cutter • Dremel Tool – can be used for deburring & • Needle-nose pliers enlargening small holes, etc. • Various open-ended & box-headed wrenches (metric)

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 5

At this point, triple check your work to make sure that nothing is missing or incorrectly modified. You are about to reassemble the amp. If you later have to debug your work, it’ll take considerable more time later. 11. Bolt back in the main PCB back into the chassis, using Loctite, but follow the hook-up sequence indicated below. a. Trim, tin and solder the OT’s Blue/Red/Blue-White leads onto their indicated locations on the main PCB. Note to cut the wires so that they can be tucked off the top edge of the board. b. Trim, tin and solder the Blue/Red/Black leads to the output PCB, and re-attach it back into the chassis. Note to tuck the wires towards the far wall of the chassis, away from the main PCB. c. Complete the hookup of the PTS and bolt it into place. Depending upon your technique, you may find it easier to bolt it into place first and complete the soldering from there. Do NOT over tighten the PTS’s retaining nut or you will strip the threads. d. Reattach the chassis ground lead (Green-Yellow), trim and tin the PT’s Green-Yellow lead – bolt them both into the chassis in the original location.

6 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

Be sure to read and follow these helpful hints and tips! Tech hint: The main PCB is double-density board – with separate circuits etched on the top and the bottom layer. It is sometimes easier to solder to the top of the board than the bottom, especially if the eyelets have been damaged in the de-soldering of the components you’ve removed. Tip: Use parts trays to hold the parts as you are disassembling the amp. Tip: When removing components from the PCB, remove all of the old solder from the holes. Also, use an electronics-approved contact cleaner to clean the board after the initial parts removal and then again after you’ve made all of the upgrades (but before the PCB is bolted back into the chassis). Note: On some “Tiny Terrors” that the retaining clips of the leads (primarily from the transformers) are “spring loaded.” The clips won’t just pull off – you have to pull back the clear plastic sheathing, and using a tiny screw driver (or something similar) push the retaining metal “lip” in while pulling off the clip.

Versions of the “Tiny Terror”: There are currently four versions of the “Tiny Terror.” The original (Version 1) was a relatively limited run and rare. Version 2 can be identified by the “Made in Korea” marking on the back of the amp. Version 3 can be identified by the “Made in PRC” (Republic of China) marking on the back and the marking “ORA-PC211-X” (where “X” is “1,” “2” or “3”) on the main PCB. Version 4 is also “Made in PRC” and has the marking “ORA-PC211-4” on the main PCB. Note: The this manual is divided into two sections, one for Versions 1, 2 & 3 and another for Version 4.

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 7

2-1/2” 2-1/2” 2” 1-1/8” 3-1/8” 3-1/8” 2-1/2” BLK BLK BLU BLU RED BLU BLU BLU RED RED BLU/WHT BLU/WHT BLU BLU RED

BLU/WHT BLU/WHT (All dimensions are nominal) NOTE: Footprint has been

slightly modified to fit the PRIMARY SECONDARY BLU BLU RED (INPUT) (OUTPUT) existing chassis holes. BLU/WHT ~1-3/4” BLUE BLACK

RED RED (8Ω) 2-3/8” 2-3/8” ~1-3/4” ~1-3/4”

BLUE/WHITE BLUE (16Ω)

ORO-TT ORO-TT BLK BLU RED for the

Origin: Billy Yates of the Venice Amp Company CLASS: Axiom® MOUNTING: Vertical TYPE: Output Transformer POWER RANGE: Our OTs are rated PART NO.: ORO-TT to handle up to 50% more power than ORIGINAL ORANGE the original manufacturer spec. PART NO: “Tiny Terror Output” DATE: 06-22-11 Copyright © 2008–11 by Mercury Magnetics. All Rights Reserved. Mercury Magnetics, FatStack, Mini-Choke & Mercury Vintage are trademarks of Mercury Magnetics. Axiom and ToneClone are registered trademarks of Mercury Magnetics. Mercury Magnetics is not affiliated with Orange.

8 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

2-1/2” 3” 2” 1-5/8” 3-1/8” 3-1/8” 2-1/2” BLK YEL YEL YEL YEL PUR PUR GRY GRY GRN GRN BR N GRN/YEL BLK BRN (All dimensions are nominal)

GRN/YEL GRN/YEL GRN/YEL BLK BRN 1-7/8”

GREEN/YELLOW (SHIELD)

GREEN 0V 0V BLACK GREY C/T B+

PURPLE 290V

YELLOW

FILAMENT 6.3V 120V BROWN

2-7/8” 2-7/8” YELLOW 2-5/16” 2-5/16” PRIMARY SECONDARY (INPUT) (OUTPUT)

Low flux/high inductance design with primary to secondary humbucking winding configuration.

ORP-TT-A ORP-TT-A YEL YEL

YEL YEL for the PUR

GRN

Origin: Billy Yates of the Venice Amp Company CLASS: Axiom® MOUNTING: Vertical TYPE: Power Transformer VA RATING: 30VA PART NO.: ORP-TT-A DATE: 04-14-08 ORIGINAL ORANGE REVISED: 10-01-09 PART NO: “Tiny Terror Main” Copyright © 2008–9 by Mercury Magnetics. All Rights Reserved. Mercury Magnetics, FatStack, Mini-Choke & Mercury Vintage are trademarks of Mercury Magnetics. Axiom and ToneClone are registered trademarks of Mercury Magnetics. Mercury Magnetics is not affiliated with Orange.

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 9

of chassis. of chassis. left corner from bottom bottom from to new holes. new holes. to Use 7/16” bit. bit. 7/16” Use Lead pass thru pass thru Lead hole re-locations: hole re-locations: rubber grommets grommets rubber 9-5/8”W x 3-1/2”H Then, swap original swap Then, (v3) EL84 (V1) 12AX7 12AX7 of chassis. left corner Use 1/4” bit. 1/4” Use from bottom from Pentode/Triode 5-3/4”W x 1/2”H Switch Location: Location: Switch is not affiliated with Orange Amps. Mercury Amps. with Orange Magnetics is not affiliated FRONT (v4) EL84 (v2) 12AX7 12AX7 for the Orange“Tiny Terror” the Orange“Tiny for Upgrade Orange Amps and Tiny Terror are trademarks of Orange Amps. Amps. of Orange trademarks are Terror Tiny and Amps Orange Chassis mods for Version 1 & 2 (Korean PCB), Version 3 & 4 (Chinese PCB) amps Version PCB), 1 & 2 (Korean ChassisVersion mods for The “Holy Terror” Terror” “Holy The . All Rights Reserved. Mercury Magnetics, “Holy Terror” and the slogan “The Heart & Soul of Your Amp” are trademarks of Mercury Magnetics. Axiom and ToneClone are registered trademarks of trademarks registered are ToneClone and Axiom of Mercury trademarks are Magnetics. Amp” “TheYour Heart & Soul of and the slogan Terror” “Holy Mercury Magnetics, Rights All Reserved. Mercury © 2008–9 by Magnetics . Copyright Lead Lead pass thru pass thru Lead Lead pass thru pass thru GROUND TRANSFORMER . The disclosure of the information herein may pertain to proprietary rights, and the furnishing of these documents does not constitute an expressed or implied license to use such materials. use such materials. to or implied license an expressed and the furnishing does not constitute of these documents pertain may herein proprietary to of the information disclosure rights, The the engineering staff of Mercury made by Magnetics . investigations of technical the result projectare This and its documentation MERCURY’S POWER MERCURY’S ORANGE indicates new hole locations hole locations ORANGE new indicates Back panel view view Top www.MercuryMagnetics.com www.MercuryMagnetics.com [email protected] (818) 998-7791 ~11-3/4” x 5-1/9” x 2” CHASSIS TOP and BACK PANEL VIEW (all specifications shown are nominal) VIEW are shown (all specifications PANEL and BACK TOP CHASSIS x 2” x 5-1/9” ~11-3/4”

10 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

ORO-PC211-X (where “X” is either “1,” “2” or “3”)

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 11

16 Ω

µ F–450V 22 C5 R13 REVISED: 02-12-10 REVISED: VERSION: 09-02-08 VERSION: 15K Ω Schematic drawn by — by Schematic drawn TRANSFORMER STOCK OUTPUT STOCK B A C www.MercuryMagnetics.com www.MercuryMagnetics.com

A1 A2

µ F–450V

Terminal Terminal 47 Terminal Terminal C6 R2 R1 R4 470 Ω− 5W 470 Ω− 5W 10K Ω

µ F–63V

V4 220

EL84 C3

µ F–450V 47

EL84

Ω –5W 120 R5 R3 150 Ω− 5W A R7

. Mercury Magnetics. R10

1.5K Ω 1.5K Ω

Ω Ω 220K

R6 R6

Ω –.25W 220K

R8 & R9 & R8

µ F–400V 100

µ F F .0022 500KL 500KL

FS2

C15 C15 RV2 RV2

Ω Ω Ω 220K 220K

RV3(B) RV3(B) RV3(A)

DUAL DUAL µ F F 500KA .01 C1 C1

TO FILAMENTS FILAMENTS TO

Ω Ω Ω 100

D3 100 D4

R16 R16 R17

C17

.1 µ F

µ F F .047 C16 C14 .1 µ F V2B

R29

1M Ω C 12AX7 Ω Ω 100K

R15 R15

Ω Ω Ω Ω 47K 1.2K

R26 R26 R27 R27 SEC

Ω Ω 100K R14 R14 is not affiliated with Orange Amps. Mercury Amps. with Orange Magnetics is not affiliated R28 1M Ω V2A PRI STOCK POWER POWER STOCK TRANSFORMER Stock Wiring Schematic Schematic Wiring • Stock C13

.047 µ F

, “Holy Terror,” the slogan “The Heart & Soul of Your Amp,” FatStack & Mercury Vintage of trademarks are & Mercury FatStack Amp,” “TheYour Heart & Soul of the slogan Terror,” “Holy Mercury Magnetics, Mercury Magnetics.

RV1(B) RV1(B)

Ω Ω 220K R25 R25 C8

Orange Amps and Tiny Terror are trademarks of Orange Amps. Amps. of Orange trademarks are Terror Tiny and Amps Orange

.047 µ F

ρ F F

470 R19

68K Ω C18 C18 P IG Ic IK 7 7 8 8

IP V1B HT Orange Tiny Terror Tiny Orange

G2 Ic

µ F F

Stock Schematic for Version 1, 2 PCB (Korean) & Version 3 PCB (Chinese) Amps Version & 2 PCB (Korean) 1, Version Stock Schematic for 1

12AX7 9 9

6 6 C11 C11

Ω Ω

100 500KA DUAL

R12 R12

Ω Ω 1.5K 5 H 5 H R24 R24 EL84 12AX7 1 1 4 4 H Ic H 2P 3 3 2 2 C10 .0001 µ F

K G1

2G 2K RV1(A) RV1(A)

Ω Ω 470K R23 R23 R22 68K Ω . The disclosure of the information herein may pertain to proprietary rights, and the furnishing of these documents does not constitute an expressed or implied license to use such materials. use such materials. to or implied license an expressed and the furnishing does not constitute of these documents pertain may herein proprietary to of the information disclosure rights, The the engineering staff of Mercury made by Magnetics. investigations of technical the result projectare This and its documentation C12

.001 µ F

V1A

µ F F 22

12AX7

C9 C9

Ω Ω 100

R11 R11 Ω Ω 1.5K R21 R21 JULY 4, 2006 4, JULY R18 68K Ω

PCB VERSION: ORA-PC211-1 VERSION: PCB www.OrangeAmps.com www.OrangeAmps.com

Ω Ω

1M LTD. ORANGE MUSICAL ELECTRONIC CO. R20 R20 C7 .22 µ F SK1

12 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

µ F–450V ORO-TT 22 C5 Mercury Magnetics Transformer Output #: PART A B R13 10K Ω 15K Ω A2 C A1 Terminal Terminal Triode Triode Triode Triode Pentode Pentode

Terminal Terminal

Pentode Pentode = PCB Modifications & Chinese Korean = PCB-only Modifications Korean

µ F–450V 47 C6 TRIODE SWITCH R4 OPTIONAL PENTODE/ 10K Ω 10K Ω R2 B 470 Ω− 5W

µ F–450V 470 Ω− 5W 47

µ F–63V

V4 220 EL84 C3 V3 R3 EL84

150 Ω− 5W

Ω –5W 120 R5 A . Mercury Magnetics.

R7 Ω Ω 220K

1.5K Ω

R10 R6

1.5K Ω

µ F–400V 100

Ω –.25W 220K R8 & R9 & R8

FS2

µ F F .0022 500KL 500KL

C15 C15

RV2 RV2 D1 D2

µ F F .01

C1 C1

Ω Ω Ω 220K 220K FILAMENTS TO

RV3(A) RV3(A)

DUAL DUAL RV3(B)

500KA

Ω Ω Ω Ω 100

D3 100 D4

R17 R17 R16 R16

C17 .1 µ F

µ F F .047

ORP-TT C16 C14 .1 µ F V2B is not affiliated with Orange Amps. Mercury Amps. with Orange Magnetics is not affiliated 12AX7

R29

SEC C 1M Ω Ω Ω

100K Mercury Magnetics Transformer Power #: PART R15 R15 for the the for

, “Holy Terror” and the slogan “The Heart & Soul of Your Amp” are trademarks of trademarks are Amp” “TheYour Heart & Soul of and the slogan Terror” “Holy Mercury Magnetics, Mercury Magnetics.

Ω Ω

47K Ω Ω 1.2K PRI

R26 R26

R27 R27 Ω Ω 100K R14 R14

R28 V2A 1M Ω

µ F F .022

C13

.047 µ F

Ω Ω 470K Amps. of Orange trademarks are Terror Tiny and Amps Orange

RV1(B) RV1(B)

Ω Ω

VOLTAGE DIVIDER VOLTAGE 220K

µ F F .022 R25 R25 P IG Ic IK 300K–320K Ω 7 7 8 8 IP HT G2 Ic 9 9 6 6

V1B Upgraded Schematic for Version 1, 2 PCB (Korean) & Version 3 PCB (Chinese) Amps Version & 2 PCB (Korean) 1, Version Schematic for Upgraded

µ F F

12AX7 1 D C11 C11

5 H 5 H

Ω Ω

50K 500KA DUAL EL84

R12 R12 Ω Ω 2.2K 12AX7 R24 R24 1 1 4 4 H Ic H 2P 3 3 2 2

K G1

RV1(A) RV1(A)

Ω Ω 470K

680 ρ F R23 R23 R22 . The disclosure of the information herein may pertain to proprietary rights, and the furnishing of these documents does not constitute an expressed or implied license to use such materials. use such materials. to or implied license an expressed and the furnishing does not constitute of these documents pertain may herein proprietary to of the information disclosure rights, The the engineering staff of Mercury made by Magnetics. investigations of technical the result projectare This and its documentation 470K Ω 100K Ω OPTIONAL RC NETWORKOPTIONAL RC

V1A

C12 C12

JULY 4, 2006 4, JULY µ µ F F 4.7 or F 10

12AX7

µ C9 F F .001 to .01

Ω Ω 100K

R11 R11 Ω Ω 1.8K R21 R21 ORA-PC211-1 VERSION: FROM BOARD ORANGE MUSICAL ELECTRONIC CO. LTD. LTD. ORANGE MUSICAL ELECTRONIC CO. www.OrangeAmps.com www.OrangeAmps.com

R18

68K Ω

Ω Ω 1M R20 R20 JUMPER LATEST REVISION: 02-12-10 REVISION: LATEST ORIGINAL VERSION: 08-20-08 VERSION: ORIGINAL Schematic drawn by — by Schematic drawn SK1 www.Amp-Exchange.com www.Amp-Exchange.com www.MercuryMagnetics.com www.MercuryMagnetics.com

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 13

J2 J2

TX4 TX4 TX3 TX3 STBY2 STBY2 STBY1 STBY1 TX2 TX1 Red Green Green Yellow Yellow C4 FS1 FS2 T4A

T250mA REVISION: 10-01-09 REVISION: R17 C1 Schematic drawn by — by Schematic drawn VERSION: 08-17-08 (original) VERSION:

D2 D1 D2 D4 D3 D4 www.Amp-Exchange.com www.Amp-Exchange.com R16

www.MercuryMagnetics.com www.MercuryMagnetics.com

5W150RJ 5W150RJ R6 R6 HTR0 HTR5

LAMP1

CT R3 R3 ORA-PC211-1 2008 16th February Designed & built by Musical Orange Ltd. Electronic Co.,

Brown Brown

TP3 C17 C17

C2 TP0 400V

Green Green

104K 104K R4 R4

LK0

R29 R29

B R2 R2

V4 V4 C6

400V 400V

R10 R10 5W470RJ 5W470RJ

104K 104K A100K

V2 HTR2 C16

473K/400V 473K/400V C15 C15

R9 R9

HTR4

Y R28

RV3 RV3

R27 R27

R15 R15

C14 C14

473K/400V 473K/400V R24 Remove

Y R14 R26 R26 R13 R13

TP5

A2 473K/400V

C3 C13 Red

R25 R25 C8 C8

of R1 & R2 TP4 473K/400V TP7 C5

A500K from the main PCB from 5W120RJ R24 R24

Remove C11 Remove

A1 If you will be makingIf you the R19 R19

ORANGE ‘Tiny Terror’ Terror’ ‘Tiny ORANGE

Black R12 Pentode/Triode switch option, option, switch Pentode/Triode disconnect the north terminals R5

R1 R1 RV2

C11

5W470RJ 5W470RJ C10 C10

R8 R8

The Pentode/Triode Switch OPTION Switch Pentode/Triode The V3 R23 R23 C18 C18 R22 R22

V1 HTR1 R7 R7

Remove C10 Remove HTR3 C12

TP6

R18 R18 R21

R11 R11 A500K C9 C9 C7 TP2

224K 250V TP1

RV1 RV1 6.3vac 6.3vac R20 R20 Remove R21 Remove SK1 Remove C18 Remove Remove R22 Remove for the the for Remove R19 Remove Remove C9 Remove the top side of the main PCB PCB main the of side top the Remove these components from from components these Remove VERSIONS 1, 2 (KOREAN) & 3 (CHINESE) (CHINESE) 3 & (KOREAN) 2 1, VERSIONS

This project and its documentation are the result of technical investigations made by the engineering staff of Mercury Magnetics. The disclosure of the information herein may pertain to proprietary rights, and the furnishing of these documents does not constitute an expressed or implied license to use such materials. Copyright © 2008–9 by Mercury Magnetics. All Rights Reserved. Axiom and ToneClone are registered trademarks of Mercury Magnetics. Mercury Magnetics, “Holy Terror” and the slogan “The Heart & Soul of Your Amp” are trademarks of Mercury Magnetics. Orange Amps and Tiny Terror are trademarks of Orange Amps. Mercury Magnetics is not affiliated with Orange Amps.

14 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

V1 VERSIONS 1, 2 (KOREAN) & 3 (CHINESE)

680ρF capacitor C9 100KΩ resistor (provided) R20 C12 (provided) (brown/black/yellow/gold)

470KΩ resistor (provided) R21 680 (yellow/violet/yellow/gold) R23 A500K RV1 R22

At PCB location R22

Optional “R C N etwor k” Detail Experiment with and without “RC Network #1” to determine your preferred tone.

“Voltage Divider” Detail

.022µF capacitors (w/kit)

100KΩ resistor (w/kit) (brown/black/yellow/gold)

piggybacks original R12 resistor R12 .022K Y Note: The “Voltage Divider” HTR2 connects, as shown, to 3 points to the Main PCB at: 300KΩ resistor (w/kit) .022K R12 (south terminal) (orange/black/brown/gold) R24 (south terminal), and V2 (at pin 8) V2 B It is best to build it separately before mounting to the Main PCB. See reference photographs for more clues. R24

2.2ΩK resistor (w/kit) (red/red/red/gold) Schematic drawn by — Optional: Use 470KΩ resistor (w/kit) insulator (w/kit) here (yellow/violet/yellow/gold)

www.MercuryMagnetics.com www.Amp-Exchange.com VERSION: 08-12-08 (original) Revised: 05-26-11

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 15

VERSION: 08-17-08 (original) VERSION: Schematic drawn by — by Schematic drawn

(brown/black/orange/gold) (brown/black/orange/gold)

J2 J2

www.Amp-Exchange.com www.Amp-Exchange.com

TX4 TX4 TX3 TX3 STBY2 STBY2 STBY1 STBY1 TX2 www.MercuryMagnetics.com www.MercuryMagnetics.com Red TX1 Green Green Yellow Yellow C4 FS1 FS2 T4A

T250mA R17 R17 C1

D2 D1 D2 D4 D3 D4

R16 R16

5W150RJ 5W150RJ R6 R6 HTR0 HTR5 LAMP1

CT Disconnect the

pentode/triode pentode/triode switch as shown as shown switch R3 R3 diagram) (see separate and connect the to north of R2 terminal ORA-PC211-1 2008 16th February Designed & built by Musical Orange Ltd. Electronic Co., Brown Brown

This cluster of components of components cluster This

is called an “Voltage Divider”“Voltage is called an TP3 RED = PENTODE TRIODE = BLUE C17

C2 TP0 400V

Green Green

R4 R4

104K 104K

LK0 R29 R29

Connect A2 to Connect A2 to R2 switch as shown as shown switch pentode/triode pentode/triode switch as shown as shown switch

V4 V4 C6

After disconnectingAfter the

400V 400V R10 R10

lead to the pentode/triode the pentode/triode lead to 5W470RJ

north this of R2 run terminal

104K 104K A100K

V2 HTR2

C16

473K/400V 473K/400V C15 C15

R9 R9

HTR4

Y R28

RV3 RV3

R27 R27

R15 R15

473K/400V 473K/400V C14 C14

Y R14 top terminals terminals top Jumper across Jumper across R26

At R24 add 2.2K Ω At resistor (provided) resistor (red/red/red/gold)

R13 R13 .022K

TP5

A2 473K/400V

C3 C13 Red

R25 R25 C8 C8 Pentode/Triode Pentode/Triode

Switch (provided) (provided) Switch TP4 473K/400V TP7 C5

A500K Mercury Amps. with Orange Magnetics is not affiliated 5W120RJ 5W120RJ R24 R24

.022K R19

ORANGE ‘Tiny Terror’ Terror’ ‘Tiny ORANGE

Black R12 R5 R5

R1 R1 RV2 The Pentode/Triode Switch OPTION Switch Pentode/Triode The

C11

5W470RJ 5W470RJ

C10 C10 C11 add 1 µ F At

R8 R8 V3 V3

R23 R23 (provided) capacitor C18 C18 R22 R22

Connect A1 to Connect A1 to

V1 pentode/triode pentode/triode switch as shown as shown switch HTR1 R7 R7

optional modification optional modification HTR3 C12

layout schematic regarding this schematic regarding layout

be mounted in the chassis before in the chassis before be mounted TP6 The pentode/triodeshould The switch R18 R18 R21

any connections are made—see chassis are any connections R11 R11 A500K C9 C9 C7 TP2 224K 250V TP1 RV1 RV1 6.3vac 6.3vac

extend the lead to makeextend the lead to the fit switch as shown—you’ll need to need to as shown—you’ll switch R20 and connect to the pentode/triode and connect the pentode/triode to Disconnect the north of R1 terminal Orange Amps and Tiny Terror are trademarks of Orange Amps. Amps. of Orange trademarks are Terror Tiny and Amps Orange At R21 add 1.8K Ω At resistor (provided) (provided) resistor (brown/grey/red/gold) (brown/grey/red/gold) SK1 Korean PCB: PCB: Korean Chinese PCB: PCB: Chinese resistor (provided) (provided) resistor Change C9 to 4.7 µ F C9 to Change Change C9 to 10 µ F C9 to Change capacitor (provided) (provided) capacitor (provided) capacitor Piggyback R13 with 10K Ω Piggyback (brown/black/orange/gold) (brown/black/orange/gold) Also see optional Also At R22 add 470K Ω At Piggyback R12 with Piggyback resistor (provided)— resistor “RC Network” diagram “RC Network” (yellow/violet/yellow/gold) north connection of R18 the upper-right terminal the upper-right terminal Solder a jumper between of input jack SK1 and the connects to the “RC #2/ Network connects the to (brown/black/yellow/gold) 100K Ω (brown/black/yellow/gold) resistor (provided)—note that it also that (provided)—note resistor (see separate diagram) diagram) (see separate Divider” Voltage for the the for . of Mercury trademarks are Magnetics . Amp” “TheYour Heart & Soul of and the slogan Terror” “Holy Mercury Magnetics, Mercury of trademarks Magnetics . registered are ToneClone and Axiom Rights All Reserved. Mercury © 2008–2011 by Magnetics . Copyright VERSIONS 1, 2 (KOREAN) & 3 (CHINESE) (CHINESE) 3 & (KOREAN) 2 1, VERSIONS Make these modifications modifications these Make to the top side of the main PCB PCB main the of side top the to . The disclosure of the information herein may pertain to proprietary rights, and the furnishing of these documents does not constitute an expressed or implied license to use such materials. use such materials. to or implied license an expressed and the furnishing does not constitute of these documents pertain may herein proprietary to of the information disclosure rights, The the engineering staff of Mercury made by Magnetics . investigations of technical the result projectare This and its documentation

16 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

To “TX1” on main “TX1” To

J2 J2

TX4 TX4 TX3 TX3 STBY2 STBY2 STBY1 STBY1 TX2 TX1 Red Green Green Yellow Yellow C4 FS1 FS2 T4A

T250mA R17 R17 C1

Green power transformer transformer power Green

lead to “TX2” on main PCB “TX2” lead to D2 D1 D2 D4 D3 D4

R16 R16

5W150RJ 5W150RJ R6 R6 HTR0 HTR5

LAMP1

CT R3 R3 indication on mainPCB indication ORA-PC211-1 2008 16th February Designed & built by Musical Orange Ltd. Electronic Co., Red output transformer Red output transformer Brown Brown

TP3 lead to “CT Brown” Brown” “CT primary lead to

C17 C17

C2 400V TP0

Green Green

104K 104K R4 R4

LK0

R29 R29

R2 R2

5W470RJ 5W470RJ

V4 V4 C6

400V 400V

R10 R10

104K 104K A100K

V2 HTR2

C16

473K/400V 473K/400V C15 C15

R9 R9

HTR4

Y R28

RV3 RV3

R27 R27

lead to “A2” “A2” primary lead to R15 473K/400V 473K/400V

indication on mainPCB indication C14

Y R14 R26 R26

Blue/White output transformer output transformer Blue/White

R13 R13 .022K

TP5

A2 473K/400V

C3 C13 Red

R25 R25 C8 C8 TP4 473K/400V TP7

A500K 5W120RJ 5W120RJ R24 R24

.022K R19

ORANGE ‘Tiny Terror’ Terror’ ‘Tiny ORANGE

Black R12 R5 R5 R1 R1 RV2

C11

C10 C10 5W470RJ 5W470RJ

R8 R8 V3 V3

R23 R23 C18 C18 R22 R22

HTR1

LK1 LK1 R7 R7

To LK0 LK0 To HTR3 C12

TP6 SK5 SK5

R18 R18 R21 amp using a variac. variac. a using amp

R11 R11 A500K before replacing the tubes tubes the replacing before C9 and test firing your modified modified your firing test and Make these final connections connections final these Make C7 lead to “A1” “A1” primary lead to TP2 224K 250V TP1

RV1 RV1 indication on mainPCB indication

6.3vac 6.3vac Blue output transformer Blue output transformer

R20 R20

Yellow/16OHM Yellow/16OHM SK4 SK4

SK1 Orange/8OHM Orange/8OHM

Mercury Amps. with Orange Magnetics is not affiliated SK3 SK3 SEE REFERENCE WIRE TWISTING WIRE

AND ROUTING/PLACEMENTS AND ROUTING/PLACEMENTS

PHOTOS FOR RECOMMENDED FOR RECOMMENDED PHOTOS

01 01 Black Black for the the for VERSIONS 1, 2 (KOREAN) & 3 (CHINESE) (CHINESE) 3 & (KOREAN) 2 1, VERSIONS Revised: 05-26-11 Revised: Diagram drawn by — by drawn Diagram VERSION: 08-17-08 (original) VERSION: Red output transformer Red output transformer indication on output PCB indication www.Amp-Exchange.com www.Amp-Exchange.com www.MercuryMagnetics.com www.MercuryMagnetics.com . The disclosure of the information herein may pertain to proprietary rights, and the furnishing of these documents does not constitute an and the furnishing does not constitute of these documents pertain may herein proprietary to of the information disclosure rights, The the engineering staff of Mercury made by Magnetics . investigations of technical the result projectare This and its documentation Amp” “TheYour Heart & Soul of and the slogan Terror” “Holy Mercury Magnetics , of Mercury trademarks Magnetics . registered are ToneClone and Axiom Rights All Reserved. Mercury © 2008–2011 by Magnetics . Copyright use such materials. to or implied license expressed Amps. of Orange trademarks are Terror Tiny and Amps Orange of Mercury trademarks are Magnetics . Blue output transformer Blue output transformer indication on output PCB indication on output PCB indication lead to “Black” “Black” secondary lead to Black output transformer Black output transformer lead to “Orange/8ohm” “Orange/8ohm” secondary lead to lead to “Yellow/16ohm” “Yellow/16ohm” secondary lead to

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 17

cription des

n tha

ferent dif

are

PTS

ndoff sta

and

ors col

d lea

t tha

e Not

3).

rsion (ve

PCB

n mai

ified mod

ly ful

to: pho

reference

Chassis

18 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

cription des

n tha

ferent dif

are

PTS

ndoff sta

and

ors col

d lea

t tha

e Not

3).

rsion (ve

PCB

n mai

ified mod

ly ful

to: pho

reference

Chassis

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 19

cription des

n tha

ferent dif

are

PTS

ndoff sta

and

ors col

d lea

t tha

e Not

3).

rsion (ve

ssis cha

ssembled rea

ly ful

to: pho

reference

Chassis

20 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

rsion (ve

ssis cha

ssembled rea

ly ful

to: pho

reference

Chassis

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 21

Reference photo showing the connections to the PTS.

22 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

This photo and those on the next 2 pages are intended for reference purposes. Note that the filament leads (the twin yellow leads coming from the PT) are the only leads that must be “braided” – which lessens RF.

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 23

26 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

ORO-PC211-4

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 27

16 Ω

µ F–450V 22 C5 R13 VERSION: 09-02-08 VERSION: REVISION: 02-12-10 REVISION: 15K Ω Schematic drawn by — by Schematic drawn TRANSFORMER STOCK OUTPUT STOCK B A C www.MercuryMagnetics.com www.MercuryMagnetics.com

A1 A2

µ F–450V

Terminal Terminal 47 Terminal Terminal C6 R1 R2 R4 470 Ω− 5W 10K Ω 470 Ω− 5W

µ F–63V

V4 220

EL84 C3

µ F–450V 47

EL84

Ω –5W 120 R5 R3 150 Ω− 5W A R7

. Mercury Magnetics . R10

1.5K Ω 1.5K Ω

Ω Ω 220K

R6 R6

Ω –.25W 220K

R8 & R9 & R8

µ F–400V 100

µ F F .0022 500KL 500KL

FS2

C15 C15 RV2 RV2

Ω Ω Ω 220K 220K

RV3(B) RV3(B) RV3(A)

DUAL DUAL µ F F 500KA .01 C1 C1

TO FILAMENTS FILAMENTS TO

Ω Ω Ω Ω 100

D3 100 D4

R16 R16 R17 R17

C17

.1 µ F

µ F F .047 C16 C14 .1 µ F V2B

R29

1M Ω C 12AX7 Ω Ω 100K

R15 R15

Ω Ω Ω Ω 47K 1.2K

R26 R26 R27 R27 SEC

.047 µ F

RV1(B) RV1(B)

Ω Ω 220K R25 R25 Stock Schematic for Version 4 PCB (Chinese) Amps Version Stock Schematic for

R19

Orange Amps and Tiny Terror are trademarks of Orange Amps. Amps. of Orange trademarks are Terror Tiny and Amps Orange 68K Ω

ρ F F 470

C8 C18 C18 P IG Ic IK .047 µ F 7 7 8 8

IP V1B HT Orange Tiny Terror Tiny Orange

G2 Ic

µ F F

12AX7 1 9 9

6 6 C11 C11

Ω Ω

100 500KA DUAL

R12 R12

Ω Ω 1.5K 5 H 5 H R24 R24 EL84 12AX7 1 1 4 4 H Ic H 2P 3 3 2 2 C10 .0001 µ F

K G1

2G 2K RV1(A) RV1(A)

Ω Ω 470K R23 R23 R22 68K Ω . The disclosure of the information herein may pertain to proprietary rights, and the furnishing of these documents does not constitute an expressed or implied license to use such materials. use such materials. to or implied license an expressed and the furnishing does not constitute of these documents pertain may herein proprietary to of the information disclosure rights, The the engineering staff of Mercury made by Magnetics . investigations of technical the result projectare This and its documentation C12

.001 µ F

V1A

µ F F 22

12AX7

C9 C9

Ω Ω 100

R11 R11 Ω Ω 1.5K R21 R21 JULY 9, 2008 9, JULY R18 68K Ω

PCB VERSION: ORA-PC211-4 VERSION: PCB www.OrangeAmps.com www.OrangeAmps.com

Ω Ω

1M LTD. ORANGE MUSICAL ELECTRONIC CO. R20 R20 C7 .22 µ F SK1

28 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

µ F–450V ORO-TT 22 C5 Mercury Magnetics Transformer Output #: PART A B R13 10K Ω 15K Ω A2 C A1 Terminal Terminal Triode Triode Triode Triode Pentode Pentode

Terminal Terminal

Pentode Pentode

µ F–450V 47 C6 TRIODE SWITCH R4 OPTIONAL PENTODE/ 10K Ω 10K Ω R2 B 470 Ω− 5W

µ F–450V 470 Ω− 5W 47

µ F–63V

V4 220 EL84 C3 V3 R3 EL84

150 Ω− 5W

Ω –5W 120 R5 A . Mercury Magnetics .

R7 Ω Ω 220K

1.5K Ω

R10 R6

1.5K Ω

µ F–400V 100

Ω –.25W 220K R8 & R9 & R8

FS2

µ F F .0022 500KL 500KL

C15 C15

RV2 RV2 D1 D2

µ F .01

Ω Ω Ω 220K 220K FILAMENTS TO

RV3(A) RV3(A)

DUAL DUAL RV3(B)

500KA

Ω Ω Ω 100

D3 100 D4

R16 R16 R17

C17 .1 µ F

µ F F .047

ORP-TT C16 C14 .1 µ F V2B is not affiliated with Orange Amps. Mercury Amps. with Orange Magnetics is not affiliated 12AX7

R29

SEC C 1M Ω Ω Ω

100K Mercury Magnetics Transformer Power #: PART R15 R15 for the the for

Ω Ω

47K Ω Ω 1.2K PRI

R26 R26

R27 R27 Ω Ω 100K R14 R14

R28 V2A 1M Ω

µ F F .022

C13

.047 µ F

Ω Ω 470K Amps. of Orange trademarks are Terror Tiny and Amps Orange

Upgraded Schematic for Version 4 PCB (Chinese) Amps Version Schematic for Upgraded RV1(B) RV1(B)

Ω Ω

VOLTAGE DIVIDER VOLTAGE 220K

µ F F .047 R25 R25 P IG Ic IK 300K–330K Ω 7 7 8 8 IP HT G2 Ic 9 9 6 6

V1B

µ F F

12AX7 1 D C11 C11

5 H 5 H

Ω Ω

50K 500KA DUAL EL84

R12 R12 Ω Ω 2.2K 12AX7 R24 R24 1 1 4 4 H Ic H 2P 3 3 2 2

K G1

RV1(A) RV1(A)

Ω Ω 470K R23 R23 R22 . The disclosure of the information herein may pertain to proprietary rights, and the furnishing of these documents does not constitute an expressed or implied license to use such materials. use such materials. to or implied license an expressed and the furnishing does not constitute of these documents pertain may herein proprietary to of the information disclosure rights, The the engineering staff of Mercury made by Magnetics . investigations of technical the result projectare This and its documentation 470K Ω

V1A

C12 C12

JULY 9, 2008 9, JULY µ F F 10

12AX7

µ C9 F F .001 to .01

Ω Ω 100K ORA-PC211-4 VERSION: PCB

R11 R11 Ω Ω 1.8K R21 R21 ORANGE MUSICAL ELECTRONIC CO. LTD. LTD. ORANGE MUSICAL ELECTRONIC CO. www.OrangeAmps.com www.OrangeAmps.com

R18

68K Ω

Ω Ω 1M R20 R20 JUMPER LATEST REVISION: 02-12-10 REVISION: LATEST VERSION: 08-20-08 (original) VERSION: Schematic drawn by — by Schematic drawn SK1 www.Amp-Exchange.com www.Amp-Exchange.com www.MercuryMagnetics.com www.MercuryMagnetics.com

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 29

Yellow Yellow Yellow Yellow

HUM BALANCE BALANCE HUM

TX3 TX3 TX4 TX4

Red Red Green Green

TX1 TX1 TX2 TX2

VR1 T4A FS2 FS2 T4A C4 FS1

T250mA

Revision: 12-30-08 Revision: R17 R17 C1 Schematic drawn by — by Schematic drawn VERSION: 12-30-08 (original) VERSION:

D2 D1 D2 D4 D3 D4 www.Amp-Exchange.com www.Amp-Exchange.com R16

www.MercuryMagnetics.com www.MercuryMagnetics.com 5W150RJ 5W150RJ HTR0 HTR5

LAMP1

CT R6 R3 R3 ORA-PC211-4 9th July 2008 Designed & built by Musical Orange Ltd. Electronic Co.,

Brown Brown

TP3 C17 C17

C2 TP0 400V

Green Green

104K 104K R4 R4

LK0

R2 R2 R29 R29

V4 V4 C6

400V 400V

R10 R10 5W470RJ 5W470RJ

104K 104K A100K

V2 HTR2 C16

473K/400V 473K/400V C15 C15

R9 R9

HTR4

Y R28

RV3 RV3

R27 R27

R15 R15

C14 C14 473K/400V 473K/400V

Y R14

R26 R26 R19 Remove

A2 A2 R13 R13

TP5 Remove R24 Remove 473K/400V 473K/400V

C3 C13 Red

C8 C8

TP4 473K/400V TP7

R19 R19 A500K 5W120RJ 5W120RJ A1 A1

Remove C11 Remove

R24 R24

ORANGE ‘Tiny Terror’ Terror’ ‘Tiny ORANGE C18

Black R5 R5 R1 R1 RV2 RV2

400VDC ARE PRESENT ON THIS PCB 400VDC ARE PRESENT ON

!!! WARNING – VOLTAGES OF UP TO TO OF UP VOLTAGES – WARNING !!! B

C11 5W470RJ 5W470RJ

C10 C10

R8 R8 V3 V3 R12 R12

R25 R25

R23 R23

Y R22 R7 R7 C12 C12

Remove C10 Remove HTR3

TP6 C9

V1 R11 R11 A500K

R18 R21 R21 TP2

TP1

RV1 RV1 6.3vac 6.3vac R20 R20 C7 224K 250V Remove C9 Remove TT15 TT15 COMBO TT15 COMBO SK1 Remove R22 Remove Remove C18 Remove for the the for Remove R21 Remove VERSION 4 (CHINESE) (CHINESE) 4 VERSION Make these modifications modifications these Make to the top side of the main PCB PCB main the of side top the to The Black and Yellow Yellow Black and The Note: supply leads are filament on this diagram. not shown Do not detach them.

T his pr oject and its documen ta tion ar e the r esult of t echnical investiga tions made b y the engineering staff of Mer cury Magnetics. T he disclosur e of the informa tion her ein may pertain t o pr oprietary righ ts, and the furnishing of these documen ts does not c onstitut e an e xpr essed or implied lic ense t o use such ma t erials . Cop yrigh t © 2008 b y Mer cury Magnetics. A ll Righ ts Reserved. A xiom and ToneC lone ar e r egist er ed tr ademarks of Mer cury Magnetics. Mer cury Magnetics, “Holy Terr or” and the slogan “T he Heart & Soul of Your A mp” ar e tr ademarks ofMer cury Magnetics. Or ange A mps and Tiny Terr or ar e tr ademarks of Or ange A mps . Mer cury Magnetics is not affilia t ed with Or ange A mps .

30 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

for the www.MercuryMagnetics.com www.Amp-Exchange.com VERSION 4 (CHINESE) VERSION: 11-16-11 “Voltage Divider” Detail .022K (marked 223K) silver mica capacitor

Y 5 4 6 300KΩ HTR2 (orange/black/yellow/gold) 3 7 or .022K 330K Ω 2 8 (orange/orange/yellow/gold) carbon film resistor 1 9 Note: you may swap this resistor V2 B for any other value up to 1MΩ for extending the clean headroom. R19 Note: It is easier to build the network separately 470KΩ before connecting it to (yellow/violet/yellow/gold) the Main PCB. carbon film resistor R26

COMPONENT SIDE VIEW OF PCB

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 31

VERSION: 12-30-08 (original) VERSION: Schematic drawn by — by Schematic drawn Yellow Yellow Yellow Yellow

HUM BALANCE BALANCE HUM

TX3 TX3 TX4 TX4

Red Red Green Green

TX1 TX1 TX2 TX2 VR1 www.Amp-Exchange.com www.Amp-Exchange.com

www.MercuryMagnetics.com www.MercuryMagnetics.com T4A FS2 FS2 T4A C4 FS1

T250mA R17 R17 of components cluster This is called a “Voltage Divider.” “Voltage is called a C1

D2 D1 D2 D4 D3 D4

R16 R16 5W150RJ 5W150RJ HTR0 HTR5

LAMP1

CT R6 Disconnect the pentode/triode pentode/triode R3 switch as shown switch of R19. Connect the remaining leads of the 3 compontents together. together. leads of the 3 compontents Connect the remaining of R19. and connect the to (yellow/violet/yellow/gold) resistors and connect together resistors and 470K Ω (yellow/violet/yellow/gold) ORA-PC211-4 9th July 2008 Designed & built by Musical Orange Ltd. Electronic Co., north of R2 terminal Brown Brown

attaches to the north to and the 330K Ω attaches terminal of R26, the south terminal to TP3

as shown. Note that the cap connects to V2’s terminal #8, the 470K Ω connects #8, terminal V2’s the cap connects that to Note as shown. C17 C17 RED = PENTODE TRIODE = BLUE

C2 400V 400V 330K Ω (orange/orange/yellow/gold) a .22K (markedmica capacitor, Use 223K) silver TP0

Green Green

104K 104K R4 R4

LK0

R2 R2 R29 R29

Connect A2 to switch as shown switch pentode/triode switch as shown switch

V4 V4 C6

After disconnectingAfter the

400V 400V R10 R10

lead to the pentode/triode the pentode/triode lead to 5W470RJ

north this of R2 run terminal

104K 104K A100K

V2 HTR2 C16

473K/400V 473K/400V C15 C15

R9 R9

HTR4

Y R28

RV3 RV3

R27 R27

R15 R15

C14 C14 473K/400V 473K/400V

Y R14 top terminals top R26 Jumper across

A2 A2

R13 R13 .022K TP5 473K/400V 473K/400V polarity)(note

At R24 add 2.2K Ω At (red/red/red/gold) (red/red/red/gold)

resistor—piggyback resistor—piggyback C3 C13 Red

F radial capacitor capacitor with a 1 µ F radial C8 C8 Pentode/Triode

Switch (provided) Switch

TP4 473K/400V TP7 C5

R19 R19 A500K Mercury Amps. with Orange Magnetics is not affiliated 5W120RJ 5W120RJ A1 A1

R24 R24

ORANGE ‘Tiny Terror’ Terror’ ‘Tiny ORANGE C18 Black R5 R5 RV2 RV2 The Pentode/Triode Switch OPTION Switch Pentode/Triode The

400VDC ARE PRESENT ON THIS PCB 400VDC ARE PRESENT ON

!!! WARNING – VOLTAGES OF UP TO TO OF UP VOLTAGES – WARNING !!! B

C11 5W470RJ

C10 C10

R1 R1 R8 R8 V3 V3

R25 R25

R12 R12 resistor R23 R23

Connect A1 to

pentode/triode switch as shown switch

Y R22 At R22 add 470K Ω At R7 R7 C12 C12 optional modification (yellow/violet/yellow/gold) (yellow/violet/yellow/gold) HTR3

layout schematic regarding this schematic regarding layout TP6 C9 be mounted in the chassis before in the chassis before be mounted The pentode/triodeshould The switch V1

any connections are made—see chassis are any connections R11 R11 A500K

R18 R21 R21 TP2 TP1 RV1 RV1 6.3vac 6.3vac

Jumper north

extend the lead to makeextend the lead to the fit switch as shown—you’ll need to as shown—you’ll switch and connect to the pentode/triode and connect the pentode/triode to R20 Disconnect the north of R1 terminal north C9 at terminal C7 224K 250V Orange Amps and Tiny Terror are trademarks of Orange Amps. Amps. of Orange trademarks are Terror Tiny and Amps Orange terminal of R21 with positive of R21 with positive terminal TT15 TT15 COMBO TT15 COMBO SK1 (note polarity)(note resistor resistor resistor resistor At R21 add 1.8K Ω At 10 µ F axial capactor resistor—piggyback resistor—piggyback (brown/grey/red/gold) (brown/grey/red/gold) (brown/black/yellow/gold) (brown/black/yellow/gold) Piggyback R12 with 100K Ω Piggyback Piggyback R13 with 10K Ω Piggyback (brown/black/orange/gold) (brown/black/orange/gold) for the the for the upper-right terminal the upper-right terminal Solder a jumper between of input jack SK1 and the left-side connection of R18 . of Mercury trademarks are Magnetics . Amp” “TheYour Heart & Soul of and the slogan Terror” “Holy Mercury Magnetics , of Mercury trademarks Magnetics. registered are ToneClone and Axiom Rights All Reserved. Mercury © 2008–11 by Magnetics . Copyright VERSION 4 (CHINESE) (CHINESE) 4 VERSION Make these modifications modifications these Make to the top side of the main PCB PCB main the of side top the to The Yellow and Yellow The Note: supply Black filament not shown leads are Do not on this diagram. detach them! . The disclosure of the information herein may pertain to proprietary rights, and the furnishing of these documents does not constitute an expressed or implied license to use such materials. use such materials. to or implied license an expressed and the furnishing does not constitute of these documents pertain may herein proprietary to of the information disclosure rights, The the engineering staff of Mercury made by Magnetics . investigations of technical the result projectare This and its documentation

32 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

To “TX1” on main “TX1” To

Yello w w Yello Yello w w Yello

HUM BALANCE BALANCE HUM

TX3 TX3 TX4 TX4

Red Red Gr een een Gr

TX1 TX1 TX2 TX2 VR1

Green power transformer transformer power Green lead to “TX2” on main PCB “TX2” lead to T4A FS2 FS2 T4A C4 FS1

T250mA R17 R17 C1

D2 D1 D2 D4 D3 D4

R16 R16 5W150RJ 5W150RJ HTR0 HTR5

LAMP1

CT R6 R3 R3 indication on mainPCB indication ORA-PC211-4 9th July 2008 Designed & built by Musical Orange Ltd. Electronic Co., Red output transformer Red output transformer Brown Brown

TP3 lead to “CT Brown” Brown” “CT primary lead to C17 C17

C2 TP0 400V

Green Green

104K 104K R4 R4

LK0

R2 R2

R29 R29

5W470RJ 5W470RJ

V4 V4 C6

400V 400V

R10 R10

104K 104K A100K

V2 HTR2 C16

473K/400V 473K/400V C15 C15

R9 R9

HTR4

Y R28

RV3 RV3

R27 R27

lead to “A2” “A2” primary lead to R15 C14 C14 indication on mainPCB indication 473K/400V

Y R14 R26 R26

Blue/White output transformer output transformer Blue/White

A2 A2

R13 R13 .022K

TP5 473K/400V 473K/400V

C3 C13 Red

C8 C8

TP4 473K/400V

TP7 C5

R19 R19 A500K 5W120RJ 5W120RJ A1 A1

R24 R24

ORANGE ‘Tiny Terror’ Terror’ ‘Tiny ORANGE C18 Black R5 R5 RV2 RV2

400VDC ARE PRESENT ON THIS PCB 400VDC ARE PRESENT ON

!!! WARNING – VOLTAGES OF UP TO TO OF UP VOLTAGES – WARNING !!! B

C11

C10 C10

R1 R1

R8 R8 V3 V3

R25 R25 R12 R12

R23 R23

5W470RJ 5W470RJ

Y R22 R7 R7 C12 C12

HTR3

LK1 LK1

To LK0 LK0 To TP6 C9

V1 amp using a variac. variac. a using amp

SK5 SK5 R11 R11 A500K before replacing the tubes tubes the replacing before

R18

and test firing your modified modified your firing test and Make these final connections connections final these Make R21 R21 lead to “A1” “A1” primary lead to TP2 TP1

RV1 RV1 indication on mainPCB indication

6.3vac 6.3vac Blue output transformer Blue output transformer R20 R20

Yellow/16OHM Yellow/16OHM 224K 250V SK4 SK4 TT15 TT15 COMBO TT15 COMBO SK1

Mercury Amps. with Orange Magnetics is not affiliated Orange/8OHM Orange/8OHM

SEE REFERENCE WIRE TWISTING WIRE SK3 SK3

AND ROUTING/PLACEMENTS AND ROUTING/PLACEMENTS

PHOTOS FOR RECOMMENDED FOR RECOMMENDED PHOTOS

01 01 Black Black for the the for VERSIONS 4 (CHINESE) (CHINESE) 4 VERSIONS Revised: 05-26-11 Revised: Diagram drawn by — by drawn Diagram VERSION: 08-17-08 (original) VERSION: Red output transformer Red output transformer indication on output PCB indication www.Amp-Exchange.com www.Amp-Exchange.com www.MercuryMagnetics.com www.MercuryMagnetics.com . The disclosure of the information herein may pertain to proprietary rights, and the furnishing of these documents does not constitute an and the furnishing does not constitute of these documents pertain may herein proprietary to of the information disclosure rights, The the engineering staff of Mercury made by Magnetics . investigations of technical the result projectare This and its documentation Amp” “TheYour Heart & Soul of and the slogan Terror” “Holy Mercury Magnetics, of Mercury trademarks Magnetics. registered are ToneClone and Axiom Rights All Reserved. Mercury © 2008–2011 by Magnetics. Copyright use such materials. to or implied license expressed Amps. of Orange trademarks are Terror Tiny and Amps Orange of Mercury trademarks are Magnetics. lead to “Orange/8ohm” “Orange/8ohm” secondary lead to Blue output transformer Blue output transformer indication on output PCB indication on output PCB indication lead to “Black” “Black” secondary lead to Black output transformer Black output transformer lead to “Yellow/16ohm” “Yellow/16ohm” secondary lead to

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 33

Version

from

“Holy Terror” “Holy

reassembled

and

Upgraded

fully

Reference photo: Reference

34 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

Version

from

“Holy Terror” “Holy

reassembled

and

Upgraded

fully

Reference photo: Reference

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 35

Reference photo showing the connections to the PTS.

36 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 37

38 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

NOTE: If you are adding Mercury’s Mini-Choke after you’ve already made the “Holy Terror” Upgrade you will probably not be able to easily remove the circuit board. So, instead of removing the PCB, you may very, very carefully drill small holes for self-tapping metal screws for the Mini-Choke. Mount and secure your Mini-Choke, pull the leads through the hole, and then follow the instructions for removing the 5 watt 150W resistor and soldering your new Mini- Choke into place. See the chassis diagram on the next page for the hole locations and sizes.

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 41

42 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

16 Ω

µ F–450V 22 C5 ORO-TT R13 10K Ω 15K Ω Mercury Magnetics Transformer Output #: PART A B C

µ F–450V A1 47 Terminal Terminal

Triode Triode Triode Triode Pentode Pentode Terminal Terminal C6 Pentode Pentode R4 10K Ω 10K Ω TRIODE SWITCH The “ McMod ” option also applies to ” versions 1, 2 and 3 Terror “ Tiny ( Mini-Choke replaces resistor R3).. OPTIONAL PENTODE/ B R2

470 Ω− 5W µ F–450V 47 R1 C2

470 Ω− 5W ®

µ F–63V

220 MM-9H-CH V4 R3 EL84 C3 V3 EL84

Mercury Magnetics Mini-Choke #: PART Ω –5W 120 R5 The “ McMod ” option A

R7 Ω Ω 220K

1.5K Ω

R10 R6

1.5K Ω

µ F–400V 100

Ω –.25W 220K R8 & R9 & R8

FS2

µ F F .0022 500KL 500KL

C15 C15

RV2 RV2 D1 D2

µ F .01

Ω Ω Ω 220K 220K FILAMENTS TO

RV3(A) RV3(A)

DUAL DUAL RV3(B)

500KA

Ω Ω Ω 100

D3 100 D4

R16 R16 R17

C17 .1 µ F

µ F F .047

ORP-TT C16 C14 .1 µ F V2B Mercury Amps. with Orange Magnetics is not affiliated 12AX7

R29

SEC C 1M Ω Ω Ω

100K Mercury Magnetics Transformer Power #: PART R15 R15

for the the for

Ω Ω

47K Ω Ω 1.2K PRI

R26 R26

R27 R27 Ω Ω 100K R14 R14

R28 V2A 1M Ω

µ F F .022

C13

.047 µ F

Ω Ω 470K Amps. of Orange trademarks are Terror Tiny and Amps Orange

Upgraded Schematic for Version 4 PCB (Chinese) Amps Version Schematic for Upgraded RV1(B) RV1(B)

Ω Ω

VOLTAGE DIVIDER VOLTAGE 220K

µ F F .047 R25 R25 P IG Ic IK 300K–330K Ω 7 7 8 8 IP HT G2 Ic 9 9 6 6

V1B

µ F F

12AX7 1 D C11 C11

5 H 5 H

Ω Ω

50K 500KA DUAL EL84

R12 R12 Ω Ω 2.2K 12AX7 R24 R24 1 1 4 4 H Ic H 2P 3 3 2 2

K G1

2G 2K . of Mercury trademarks are Magnetics . Amp” “TheYour Heart & Soul of and the slogan Terror” “Holy Mercury Magnetics , of Mercury trademarks Magnetics . registered are ToneClone and Axiom Rights All Reserved. Mercury © 2008–10 by Magnetics . Copyright

RV1(A) RV1(A)

V1A

C12 C12

JULY 9, 2008 9, JULY µ F F 10

12AX7

µ C9 F F .001 to .01

Ω Ω 100K ORA-PC211-4 VERSION: PCB

R11 R11 Ω Ω 1.8K R21 R21 ORANGE MUSICAL ELECTRONIC CO. LTD. LTD. ORANGE MUSICAL ELECTRONIC CO. www.OrangeAmps.com www.OrangeAmps.com

R18

68K Ω

Ω Ω 1M R20 R20 JUMPER Schematic drawn by — by Schematic drawn LATEST REVISION: 04-08-10 REVISION: LATEST VERSION: 08-20-08 (original) VERSION: SK1 www.Amp-Exchange.com www.MercuryMagnetics.com

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 43

The Mini-Choke replaces this resistor (R3)

Pictures 1 & 2: These show the removal of the circuit board. Disconnect the filaments to the pilot light. Also, clip and remove resistor R3. Leave yourself plenty of the resistor’s lead wire so that you can easily bend a hook to solder the Mini-Choke leads into place.

44 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

Picture 4: This shows where the new 9 Henry Mini-Choke will be placed near the Power Transformer (see the chassis diagram at the first of this section for the exact placement). Mark the holes and carefully drill the 2 holes for Mercury’s Mini-Choke.

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 45

Picture 6: The chassis with the new Transformers and the Mini-Choke in place looks great!

46 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

Picture 8: Solder the Mini- Choke leads onto the old resistor wires of R3.

REMEMBER to add a little shrink tubing to the ends of the Mini-Choke leads.

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 47

To Make the “McMOD” Give Mercury a call. You’ll need Mercury Magnetics’ Mini-Choke (Part No. MM-9H-CH). Also considering experimenting with other choke values. Mercury makes a Multi-Choke compatible with this amp size (Part No. MM-MULTI-9C). This version of the Multi-Choke can be set from 1 Henry to 9 Henry in single Henry increments. Enjoy!

The Mercury Mini-Choke The Mercury Multi-Choke

48 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

Using a Variac & Current Meter Don’t power-up your amp without ’em! NOTE: IF YOU ARE NOT A QUALIFIED AMP TECH, DO NOT ATTEMPT TO POWER UP YOUR MODIFIED AMPLIFER, YET. INSTEAD, Mercury RECOMMENDS THAT IT BE INSPECTED BY A QUALIFIED TECHNICIAN. AN AMP TECH WILL GO OVER YOUR WORK AND VERIFY THAT IT IS SAFE TO POWER IT UP.

After modifying your amp, the next step is to power it up using a variac and current meter. The Variac and current meter allows you to slowly add voltage while checking the indicators to make sure that your handiwork is correct. Without a variac you run the extreme risk of frying your amp or some of its components, getting hurt, electrocuted, etc. A Variac is a standard amp tech tool. No amp tech should be without one. They are available from many electronic stores or online, eBay, etc. Prices start at about $50 and go up from there. The better units (such as the Tenma isolated variable AC power supply shown in these photos) include output current metering. Consider that the cost of a Variac is free, because a single error without one can easily cost more than the Variac itself! As the following instructions show, you’ll need to monitor the output current while increasing power to the amp with the Variac. If your Variac doesn’t have a self-contained current meter this can also be done with a separate amperes meter connected to the fuse-holder of the amp (with the fuse removed). Specific instructions for how to use Variacs and current meters are beyond the scope of this manual. Check the web or owner manuals of the devices for specific methods.

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 49

Variac: A variable transformer used to vary AC voltages. Also the tradename for a brand of variable AC transformer. There are other brands, but the term is generically used to describe all of them. A variac allows adjustment of the incoming AC mains voltage. The better quality units have meters for voltage and current, or both, and fuses for protection. Variacs come in many shapes and sizes. But their function is basically the same. If your variac does not have an amperes (current) meter, you’ll need to use a separate meter. NOTE: The Variac in the photo to the left does not have an amperes meter whereas the Tenma model does.

50 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

STEP C: While watching the current (amp) meter, slowly roll on the Variac’s output voltage knob. The amp should turn on at about 45 volts.

When you get to about 60 volts you don’t want to see more than a few hundred milliamps. If the current meter reaches anywhere above half an amp, roll the Variac back to zero, shut everything down, discharge the caps, and look for the error, short or bad component. Correct the problem and repeat until this test passes.

STEP D: Once you can reach 120 volts drawing less than half an amp, you are in good shape.

NOTE: If you don’t have a current meter on your Variac, remove the fuse from the amp, and with an amp meter across the empty fuse holder socket, turn on the amp and perform the test above.

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 51

PCBs cost substantially less to produce than their predecessors, i.e. point-to-point circuit boards. And are used by amp manufacturers to maintain affordable prices for consumers.

On a PCB components are often attached to the top of the board and then soldered from the back via pass-through conductive “eyelets” where they follow the copper traces that make up the circuit.

Asian-made PCBs are typically not as resilient as Repair to a damaged eyelet: The lead from component bypass- es the damaged eyelet and is soldered to either a revealed trace 2 or another terminal on the same trace (as in this example). those made in the west. Therefore they’re likely to require patching and repair work as you make the 1 3 Upgrade. This is normal, and easy to do – as long as you know a few tricks.

Revealing a Trace: Sometimes we need to “reveal” traces so that the PCB can be modified or repaired. 4 An easy way to do this is to take a sharp knife or Exacto and carefully scrape away the lamination 5 to “reveal” the copper foil under it. Use high-grade (99%) Isopropyl alcohol and a Q-tip to clean these Various examples: 1. Jumper. 2. Jumper. 3. Trace repair new contacts before soldering to them. (jumper soldered from terminal to terminal on same trace). 4. Trace repair (ditto). 5. Damaged eyelet repair (lead is soldered to a revealed trace). Continued on next page è 52 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

Or, if there’s a nearby soldered connection on the Various examples: This photo shows a cut trace, and a com- same trace, you can use the component’s lead to ponent lead jumpered and soldered to a revealed trace. It’s best jumper directly to the terminal. to not drill a hole directly into a trace. Instead make the hole off to the side of the trace and then, as in this example, solder the If an eyelet is damaged or missing or the trace component’s leg to the trace. material around it is very thin, then you may consider soldering a reinforcement jumper across it. or a Dremel Tool with a cutting or grinding edge attachment to make the cuts. How to Cut a Trace: A “trace” is the conductive strip (foil) on a printed circuit board. It has a very A trace cut severes the embedded metal laminent thin laminate or lacquer layer over it. Cutting a trace on a PCB. The purpose of a trace cut is to modify or is like clipping a wire. Use a box knife, Exacto knife re-route the electrical flow of the circuit.

Here’s two 1 2 different ways to cut a trace:

Dremel Tool

Trace cut

OR 1 2

3 4

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 53

This photograph shows a twisting pattern that you should aim for. Consistent, even twisting is important. Ideally about 10 twists per inch. Cable tie these leads as high off the Main PCB as possible, and as close as possible to both the power transformer. This will minimize amp noise and hum.

54 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

RP LPL LSL RS

C1 LP RH RE C2

C1 Primary Self Capacitance LP Primary Inductance C2 Secondary Self Capacitance RP Primary Resistance C3 Interwinding Capacitance RS Secondary Resistance LPL Primary Leakage Inductance RE Core Eddy Current Losses LSL Secondary Leakage Inductance RH Core Hysteresis Losses “Blessed are the Tone Makers” The above circuit reveals the properties of an audio output transformer. The transformer is a reactive component—its values change depending upon the information feeding it. Transformers for tube-based electric guitar amps are designed to intentionally provoke the tubes into distortion— the polar-opposite of demands of hi-fi. The best guitar tone comes from harnessing and manipulating the inherent flaws of the imperfect transformer. This is where art meets science in our pursuit of great guitar tone. —Sergio Hamernik

Consider the above vs. this typical dummied-down transformer symbol

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 55

Players who know tone insist on Mercury Magnetics transformers 9167 INDEPENDENCE AVE. • CHATSWORTH, CA 91311 • (818) 998-7791 • FAX (818) 998-7835 www.MercuryMagnetics.com Copyright © 2006 by Mercury Magnetics. All Rights Reserved. Mercury Magnetics, ToneClone, Mercury Vintage, FatStack, Mini-Choke, M.A.G.I.C. and VoodooScrew are trademarks of Mercury Magnetics. Axiom and Multiple Arrayed Geometric Inductive Coupling® are registered trademarks of Mercury Magnetics. DANGER! READ ME! DISCHARGE THOSE FILTER CAPS!!!!!

The following is a collection of notes on discharging Filter Capacitors Compiled by the staff at Mercury Magnetics

DISCHARGING CAPACITORS – The filter – OR jumper the power amp tube plate pin to capacitors in an amp will retain a charge for quite ground for a minute or so (Class A, single power some time after the amp is shut off and unplugged. tube only) It is a good idea to make sure your amp is safe – OR jumper the positive (+) lead of each large to work on. One way is to take a wire with an cap to ground for several seconds. A jumper with INSULATED alligator clip on each end, clip one a built-in resistor (10K or so) will help prevent end to a good ground point, and the other to one sparks here. of the plate leads for the first stage preamp tube. Another method would be to put a 100K, 5W or Some or all of these methods may result in a spark. more resistor in line of these two clips by attaching Obviously, your flesh can act as a jumper also. one end to ground (first), then the other to the filter caps themselves. NEVER SHORT THEM OUT It’s NEVER a good idea to touch amp circuitry when DIRECTLY! it’s switched on. And don’t work on amps in bare feet, or on a damp basement floor. BE THE ONE-ARMED TECHNICIAN – There will come a time when you have to work on a * * * chassis that is running. When doing so, if possible Letting the capacitors discharge slowly is preferable clip one of your meter’s test leads to ground, and to having them do it all at once through your body use only one hand to probe the circuit, keeping while you’re poking around inside the amp. Having the other in your pocket, etc. That way if you DO the supplies you need on hand makes the job go take a shock, your heart is not in line of the path faster. of least resistance – in one arm and out the other. When you ABSOLUTELY must use two hands, be You’ll want screwdrivers, contact cleaner (you can EXTREMELY CAREFUL, and use common sense, use Gunk brand choke and carburetor cleaner or but PLEASE try to avoid these situations! WD-40), a toothbrush and – unless you own an air compressor – an aerosol can of compressed air – * * * soldering supplies and a volt/ohm meter (learn how to use them!). “Filter” caps can store fatal amounts of electrical current. The caps are connected near the rectifier Start by unplugging the amp from the wall, the and are part of the power supply, and aid in speakers from the amp, and removing the amp converting AC to DC. In fact, they are a standard chassis from the case. For Fender amps, removing component in any power supply. the chassis involves unscrewing the upper back case panel, then unscrewing the chassis from the If you’re completely lost, and don’t understand this, top of the case. Put the screws, nuts, and lock DON’T MODIFY YOUR AMP. You haven’t enough washers where they won’t get lost. knowledge to work on high voltage/current circuits safely. With the chassis out of the case, you can locate the filter capacitors you’ll want to avoid touching as Several ways to discharge caps: you perform the tune-up. These will be cardboard cylinders (usually orange or tan or vintage Fenders) FIRST, UNPLUG THE AMP! (But that doesn’t with “+” printed near one terminal. It’s also a good make it safe!) idea to steer clear of wiring connected to the power transformer because it’s a discharge path for the THEN, take a screwdriver or a jumper and short filter capacitors. the capacitors leads.

56 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

This project and its documentation is the result of technical investigations made by the engineering staff of Mercury Magnetics. The disclosure of the information herein may pertain to proprietary rights and the furnishing of these documents does not constitute an expresed or implied license to use such materials. If you haven’t given the capacitors a couple of days such as PVC tubing or a dowel rod. Make sure to discharge – or if you just want to be cautious – enough of the copper wire is exposed to act as a you can use a short length of insulated wire with contact point. alligator clips on the ends to discharge them. First, make certain that the amp is unplugged. Attach Step 5: Attach the alligator clip to one of the one alligator clip to a capacitor’s positive (+) lead, capacitor’s leads. Be sure the amplifier is then touch the other clip to the amp chassis several completely powered off before doing so. times. Repeat the procedure for each capacitor Step 6: Touch the bare wire end of the PVC tube marked with a voltage (VDC) rating higher than 25. or dowel rod to the other lead of the capacitor. It The time spent on this precaution can spare you is very important to not touch any of the exposed from a numbing electric shock that you’ll remember leads or wires at this time. Hold the bare wire on the long after the amp is back together. lead for at least several seconds to fully discharge the capacitor. How to Discharge a Power Step 7: Test the capacitor with a multimeter to be Capacitor in Tube Amp sure all voltage has been safely removed. by Kevin Krause eHow contributing writer Discharging Capacitors To be able to properly test and troubleshoot your in a Guitar Tube Amp tube amplifier with a multimeter it is important to Take pride in how safe you can be. discharge the capacitors located in the amp’s power You can’t play guitar or build amps if you’re dead. section to avoid false readings. Capacitors act as short-term batteries, storing a charge that can be You may have heard various horror stories about called on by other components. This charge will things inside amps that can store a charge that can remain in the capacitor even after the amp has kill you. Well, it’s true! However, those dangerous been powered off, and can produce misleading voltages can be easily drained in just a few voltage readings along circuit paths. Because of the minutes, so take your time and don’t rush. high level of the stored power in the capacitor, safe It is absolutely vital that we drain the filter capacitors discharging is a must. in the DC power supply before working on any Things you’ll need: guitar amplifier. These often hold a charge of 1. High wattage resistor several hundred volts, which is potentially deadly. 2. Alligator clip Capacitors can hold their charge for a long time, 3. Copper wire even with the power off and the amp unplugged. It’s 4. PVC tube or dowel rod very important that we learn to properly “drain” this 5. Soldering iron residual voltage so that we may safely work on the 6. Solder inside of our amplifiers. 7. Multimeter What You’ll Need: Instructions Level of difficulty: Moderate Step 1: Strip about 1/4 inch of insulation off each end of a 2-foot length of insulated copper wire, and solder one end of the wire to one of the leads of a high wattage resistor. The resistance required can be determined by adding 5 to 50 ohms per volt of the capacitor’s rating. For instance, a 100V capacitor would require a resistor rated anywhere from 500 to 5k ohms. Step 2: Attach the other end of the wire to an alligator clip. Filter Capacitor Discharge Tool Step 3: Solder the free lead of the resistor to a short piece of bare copper wire. 1. Safety glasses. Always use safety glasses. If you wire a capacitor in backwards there is a very Step 4: Tape the resistor and bare copper wire to good chance that it will explode in your face. one end of a length of non-conductive material, Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 57

This project and its documentation is the result of technical investigations made by the engineering staff of Mercury Magnetics. The disclosure of the information herein may pertain to proprietary rights and the furnishing of these documents does not constitute an expresed or implied license to use such materials. 2. Digital multi-meter. Capable of reading 500 “Shorting” with a screwdriver will almost instantly volts DC. drain the caps to zero volts, causing sparks from high current. This is not acceptable. If there are 3. Capacitor discharge tool. A jumper wire several hundred volts stored in the caps, be consisting of alligator clips on the ends, with a prepared for a nice sized spark. It will most likely resistor in series in the middle of the jumper. leave a black mark on the chassis, and in extreme 4. Needle nose pliers. With very good insulation cases, partially weld the screwdriver to the chassis. on the handles for holding the alligator clips of the capacitor discharge tool. Now we’re ready to start testing and Always make sure your tools are in good condition. discharging If there’s any question, replace them. Cracked insulation is one of the first things to check, and Set your multi-meter to read DC voltage. Adjust check often. the meter’s range so that it’s above 500 volts. Clip the black lead of your multi-meter to the chassis. Turn the power switch OFF, and place the standby Using only one hand, with the other hand far from switch in the ON position. This isn’t the same as the chassis (preferably in your pocket or behind having your amp “on standby.” your back), measure the DC voltage across one Always unplug the amp from the wall. Unplugging of the filter capacitors. You can adjust the meter’s from the wall will not drain the filter capacitors range down if you can’t get a clear reading. Any DC completely, but again this is for our own safety. voltage readings less than 5 volts are harmless, so Unplugging is the equivalent to “locking out” before the amp can be safely worked on, but do a double working on a downed machine. check of all the caps just to make sure. If not we must drain off the residual voltage with a resistor Because filter caps are almost always of the until it is safe. electrolytic type, they’re “polarized” and therefore have a positive and negative end. We can identify Use a resistor value somewhere between 10K and the positive or negative ends by looking for the 100K, with a power rating of 5W or so (a high power “polarity indicator” printed on the cap’s side. rating is not really necessary for heat dissipation reasons, but mainly because the higher power Our first objective is to check for residual voltage resistors are physically more robust and won’t tend with a multi-meter. In some cases most of the to break). The larger the resistor value, the longer it voltage may have already been drained. Many will take to discharge. If your capacitors do not have amplifiers will incorporate “bleeder” resistors, which a dangerously high voltage, say around 30 volts, will drain the capacitor charge automatically in feel free to use a smaller 1K 1 Watt resistor. a few minutes after the amp is turned off. Don’t depend on this resistor to do the job. Never assume Now take your capacitor discharge tool and clip the caps have been drained to a safe level without one side to the chassis. Always clip to the chassis checking with a reliable multi-meter. ground first before connecting to the circuit. If you clip to the circuit first you will have a hot wire Here’s a couple of ways to measure the residual hanging out of your amp, which is very dangerous. voltage contained in the filter capacitors. Note that Once you have one side clipped to the chassis, these are also equally valid for draining the caps: take your needle nose pliers with good insulation on the handles and hold the alligator clip that will go to 1. Across the capacitor. the circuit with the needle nose pliers. 2. From the positive side of the cap to the Clip this to pin 1 or 6 of the first preamp tube. This chassis. This is essentially the same as seems to be the safest way of discharging the draining “across” the caps since the negative capacitors. If you’re working on the first preamp side is at the same electrical potential as the tube socket, then clip your discharge tool to pin 1 or chassis. 6 of the second preamp tube. Wait a few minutes 3. From the chassis to a tube pin. This can be (about 5 minutes, if the amp has bleeder resistors done at pin 3 of any power tube, or pins 1 or this time will be shorter) then, while the discharge 6 of any preamp tube. By shorting the chassis tool is still in place recheck all the capacitors with to the correct pin the caps will be forced to your multi-meter and keep that other hand behind drain through the plate load of that tube. This you. Keep checking until the voltage has reached prevents sparking from high current. a safe level. Note: This procedure must be done every time you turn the amp on then off. IMPORTANT NOTE, HOW NOT TO DO IT: In old electronics books they tell you to use a screw driver Remember to remove the discharge tool before with an insulated handle to short out the caps. powering on the amp. Make it a bright color like

58 Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit

Orange “Tiny Terror” • Mercury “Holy Terror” Upgrade Kit 59