Released in December 1957, the TR-63 Was Sony's First Pocket-Size Transistor Radio
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Released in December 1957, the TR-63 was Sony's first pocket-size transistor radio. It's a 6-transistor superhet design with some interesting design features, including the use of Sony-manufactured NPN transistors in the circuit. Masaru Ibuka served with the Impe- used in schools and courts. much discussion, Sony's research labo- rial Navy Wartime Research Committee Following Ibuka's visionary 1952 ratory head, Mikato Kikuchi, suggested during World War 2, leaving in 1946 to trip to the USA to sign a licence with dropping Bells' preferred doping agent, join Akio Morita to form Tokyo Tsushin Western Electric, Sony acquired pat- indium, and substituting phosphorus Kogyo Kabushiki Kaisha, "Totsuko". ent rights for the transistor and subse- instead. When that didn't work, Morita Morita, a physics graduate, had served quently began manufacturing portable called for "more doping"! alongside Ibuka in the Research Com- radios in 1955. It soon paid off and Sony were able mittee, and their friendship laid the to produce the transistors used in their foundations for the international pow- Early difficulties first solid-state radios. Their TR-55 erhouse we now know simply as Sony. Sony preferred NPN transistors be- model, released in 1955, is now a rarity Tokyo Tsushin Kogyo's first prod- cause of their better high-frequency and the last one to be listed online some uct, a rice cooker, says a lot about the response but were initially unable to years ago had a price tag of $US1500. company. Japan had suffered massive produce working examples. One can only imagine the energy destruction during World War 2 due to NPN devices exploit the fact that invested by Sony to leap from Ibuka's bombing and people needed utensils to electrons move more quickly than licensing agreement to a marketable cook their staple food, which was rice. holes, ie, they have higher mobility. transistor radio in just three years. It's So a rice cooker that simply used two This is critical in the base region and also possible to imagine their frustra- insulated metal plates ingeniously met it's here that low mobility has the most tion at being pipped at the post by Re- a vital need. That combination of op- effect on high-frequency performance. gency's TR-1 transistor radio (SILICON portunity and ingenuity set the model The problem is that NPN devices were CHIP, April 2013), which was released for Sony's future. Their first radio- more difficult to manufacture using less than six months before. related product, a shortwave converter germanium feedstock. Sony's first "pocket-size" transistor for broadcast-only radios, helped open Knowing that, theoretically, NPN radio, the TR-63, was subsequently Japanese society up to the wider world. transistors were the way to go, Sony released in December 1957. It was, Tape recorders subsequently became saw experiment after experiment fail to however, reputed to be too big for a a major product line and were widely demonstrate useful performance. After standard shirt pocket and the story goes 82 SILICON CHIP siliconchip. corn. au R9 220 R11220 W1 on Vol Cont. • R16 m 5attery 27 k 1 XS 9V DS L121112 2766 1743 R14 7: IIIMICO C13 C16 200 p R2 t 20 T2 — C3 R17 G.. ToPert 27524 42R Red (5 10 n T R1 5 k D. RIB White Volume aig 42 R RB C14 C2 it Speaker 3k3 30 8 ohms NOTES: RF voltages 30 % modulated, 400 Hz, audio 400 Hz, 10 mW output. Resistances in ohms unless k = x1000, all10% unless otherwise. Drawn: lan Charles Batty, 12107/2015) Capacitances: whole numbers/ p = picofarads, n o nanofarads, n = microfarads. DC voltages with VTVM, no signal, thus 0 except max signal thu RFIAudio signal injections Fig.1: the circuit uses six NPN transistors (X1-X6). X1 is the converter stage, X2 & X3 are IF amplifier stages, X4 is an audio pre-driver and X5 & X6 form a push-pull audio output stage. that, for its launch, Sony had special The TR-63 of 1957 cracked open the The TR-63 N shirts made with pockets that could US market and launched the new in- was one of 1, take the radios. dustry of consumer microelectronics". the last sets With total exports to the US alone with Sony's Sony's TR-63 of about 100,000, the TR-63 was a true old "lighting bolt" logo. At first glance, Sony's TR-63 is a runaway success. pretty conventional 6-transistor set, The accompanying photo of the TR- with three transistors used in the RF/ 63 shows the red "Conelrad" marks IF section and the other three in the on the dial at 640kHz and 1240kHz, audio amplifier stage. All the transis- as required by US law at that time. So tors were manufactured by Sony and what was "Conelrad"? they are all NPN types. Basically, this acronym stood for onauseum.org and other sites. Any im- As noted above, Sony preferred NPN CONtrol of ELectronic RADiation and portant differences between the R-6C2 transistors because of their better high- was set up in the US in 1951 to pro- and R-6C1 are noted in the following frequency performance. My set was kit- vide emergency radio warnings to the circuit description and on the circuit ted out with the rectangular TO-22 can public during the Cold War. If an alert diagram. transistors, the same style as used by was received, most radio stations were Converter stage X1 uses base injec- Texas Instruments in the Regency TR-1. required to cease transmission, while tion and a cut-plate tuning gang (ie, the Sony's hand-held TR-63 was offered each remaining station was to move oscillator section is smaller than the in lemon, green, red and black. It used to either 640kHz or 1240kHz. They antenna section), so there's no need for a miniature, solid-dielectric "poly- would transmit for several minutes a padder capacitor. This stage follows varicon" for the tuning capacitor and and then go off the air, and another the common practice of fixed bias, so it also required a new battery design station would take over on the same gain control is left for the following that became the iconic "PP9" and set frequency in a "round robin" chain, IF section. the standard for transistor radios. the idea being to confuse enemy air- The first IF transformer (L3) uses As a piece of portable electronics, the craft that might be navigating using a tapped, tuned primary and an un- TR-63 is a winner. It's small enough to radio direction finding. tapped secondary and this feeds the pop into my shirt pocket, something By law, radio sets manufactured be- first IF amplifier stage which is based which couldn't be said for the TR-1 tween 1953 and 1963 had the required on X2. This stage is gain-controlled and other early sets from Raytheon, GE frequencies marked by the triangle-in- by the DC voltage fed back from the and Zenith. It also fits the hand better, circle (CD Mark) symbol of Civil De- demodulator. Unusually, X2's bias is the rounded edges giving it an easier fence, so that the set could be quickly derived from a voltage divider (R6 & feel than many others. tuned to either 640kHz or 1240kHz. R7). While this would usually provide What's more, the TR-63 is a good constant bias and thus constant gain, performer. It's also one of Sony's last Circuit details R6 and R7 have higher values than sets with the old "lighting bolt" logo Several circuit variations exist (de- usual and this allows "relaxed" control that was superseded by the "Roman noted by the circuit board number) and of X2's base voltage. text" logo we're more familiar with. As these are based on either the early pro- Basically, this allows the AGC cir- well, it carries the "Totsuko" stamp on duction R-6C1 sets or the later R-6C2 cuit to control X2's gain but with less the rear cover. version. The circuit shown here (Fig.1) effect than in the circuits commonly But it's not just an elegant personal is based on my R-6C2 and is also the used in other sets. radio. It's described thus in Schiffer's version shown in an H. W. Sams Pho- The second IF amplifier is based on The Portable Radio in American Life: tofact. transistor X3 and this gets its bias from ". (Sony) was not first, but its tran- In addition, the schematics for both X2's emitter, so AGC is applied to both sistor radio was the most successful. versions are available on www.radi- IF stages to give effective control. Note siliconchip.com.au JANUARY 2016 83 which is shunted by a top-cut capacitor Output Output in both versions. T2 in turn drives a 3.5- inch (89mm) internal speaker via an Bias earphone socket. The earphone socket FAD, disconnects the loudspeaker when an Diode AY-0-VAt. 1 earphone is plugged in. MALLORY : R OR EQUiV LEN Initial tests 1st Converter This was another easy set when it Audio 1 came to restoration, at least as far as Earphone its appearance was concerned. A good clean and a light polish were all that OSC', Socket were needed to restore it to near-new condition. A quick check of the ear- Coil phone socket revealed that it was OK and I gave the volume control a light spray of contact cleaner to ensure trou- ble-free operation.