Hello! I have a portable radio tape with both Si and Ge transistors - Craftsman or 'Record O Matic' Record-0-Matic Radio Craftsman; Chicago, Illinois., build 19 . It had some problems on tape, poor sensitivity on AM, overlap on some FM near stations ecc. Hardly I have solved a part of them including new socket for power cable, new socket for batteries, new capacitors. By mistake I broke a pin from the final transistor 2SB364. I can't find this, but can I replace it with either a pair of 2SB324 or a SFT323?
Here is the diagram (taken from the radio).
Here is the diagram (taken from the radio).
An externally hosted image should be here but it was not working when we last tested it.
Thanks. I saw on a Panasonic diagram which also worked at 9V that they used 2SB324. Should it work?
An externally hosted image should be here but it was not working when we last tested it.
The 2SB324 should be fine. There so many very similar transistors at that time that will work. The EBC pinout was pretty standard too.
Does anyone have an account on RadioMuseum for helping me taking this diagram: AM/FM Cassette Tape Recorder Radio Orion Electric Co., ? This is another radio tape very similar to the model I have and the diagram would have a better quality scaned that the once I have. Thanks a lot!
> RadioMuseum ...: AM/FM Cassette Tape Recorder Radio Orion Electric Co., ?
That's not a good scan, and it is not remotely like the plan you post in #1. (Note transformer[less].)
Replace both final transistors with the same type number new Germanium. Change the emitter resistors to 10X their present values (to ensure it won't burn-up right away). Smoke-test. Measure voltage on emitter resistors. I would expect your plan to idle at 10mA to 50mA (not fussy). If, with 10X emitter resistors, it idles at 1mA-5mA, all is well. Change the resistors back and it should play OK.
That's not a good scan, and it is not remotely like the plan you post in #1. (Note transformer[less].)
Replace both final transistors with the same type number new Germanium. Change the emitter resistors to 10X their present values (to ensure it won't burn-up right away). Smoke-test. Measure voltage on emitter resistors. I would expect your plan to idle at 10mA to 50mA (not fussy). If, with 10X emitter resistors, it idles at 1mA-5mA, all is well. Change the resistors back and it should play OK.
Attachments
An AC128 is near identical.
The collector on both are the coloured dot or tab unlike the silicon type transistors.
ac128 transistor | eBay
2SB364/8023 NTE Equivalent NTE102A TRANSISTOR PNP GERMA... - Wholesale Electronics
The collector on both are the coloured dot or tab unlike the silicon type transistors.
ac128 transistor | eBay
2SB364/8023 NTE Equivalent NTE102A TRANSISTOR PNP GERMA... - Wholesale Electronics
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