Transistor Radios

Strictly speaking, all "transistor" radios and "solid state" radios use the same technology, though in the world of radio collecting, "transistor" means a solid state portable. To recap a transistor set. Typical circuit diagram.

First, a transistor from Australia:
Note that Australian radios from the 30's thru the 60's were almost always "stationized".

..Pioneer>


Same company that did the Yorks down below. Not related to Firestone.

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Careful, the earphone jack on this rechargeable set is "hot" to the powerline!



The above center AM transistor is Lafayette #17-0102L, on the right is an AM/FM set Lafayette #99-3524
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I replaced all the carbon comp resistors (they drift higher resistance out of spec) with surface mount resistors on the back of the circuit board. The circuit lands are usually close together enough to allow bridging them with the larger SMD's. This also makes it easier on the circuit board, as one isn't trying to poke new resistor leads thru the board. Thus less likelihood of lifted traces. And the circuit paths are shorter (which doesn't really matter on AM MW radios, but would at VHF frequencies). Here's the circuit board after this work. Most of the resistors you can't see, as they are now SMD's on the other side of the board. Below is this back side (you should be able to spot the SMD's):


The above Lafayette looks just like this above Koyo 10 transistor.
My brother got the Lafayette new, model FS-129L, mid 60's.

1960:


"Nipco 8 HI-FI 8 transistor" from Japan, of course..

Its front end uses a white "pill" transistor usually found in FM mixers.

This radio above uses no transistors unless you count the thousands of transistors inside the two IC's used.

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- Inside Starfire


A Starfire 12 transistor radio. All they really did was take a 7 transistor circuit and added in parallel a 2nd transistor to each of the original transistors except for the audio preamp stage and the output stage driver. Thus a "12" transistor! The converter circuit, 1st IF, 2nd IF, and push-pull audio output stages all had paired transistors. Base to base, emitter to emitter, and collector to collector. This doesn't really add anything to the performance of the radio as only one of the pair (the one with the lower B-E voltage drop) will conduct any current and thus do all the work. It was just marketing hype. And it looks like they borrowed the album artwork from Ferrante & Teicher's LP record "Soundproof". Ferrante & Teicher used art from M.G.M. Pictures - producers of "Forbidden Planet"


In the USA, its AM band picks up a few nav beacons, on its FM band it gets a TV sound carrier.

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Just like my first radio, the Lafayette #17-0102L above


This one above is the 8 transistor version. A converter instead of a mixer transistor and an oscillator transistor, and only one instead of two audio driver transistors.


This above radio has an RF stage with 3 gang tuning cap. A good DXer.

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This radio has my name on it! model: 010