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Identify OLD Electronic Components! Answered

So today, i found a VERY old radio, it was the size of a cabinet!
it had;
some 2 12"s (the voice coil diameter is about 1.5")
2 horn drivers!
120v transformer, 30Vac 3 Amps, 5.5Vac 6 Amps

Anyway, i pulled some transistors (not vacuum tubes, which was what i was hoping for) out, and i need to identify them! and find the data sheet too

Thank you in advance!

The last picture, those are npn transistors with hFE of 300


Wow... The circuit board is interesting, most of the tracking, is curved...

. I didn't come up with much. :(
. First pic looks like power transistors (audio out?), but nothing turned up on Google
. Second & third pics look like a transistor. No details found.
. Fourth pic looks like a 7009 9V regulator. (That looks like "274" to me)
. Fifth pic is transistors. EBC = Emitter Base Collector. No info found.
. You may be able to find a schematic by searching for the model number of the radio.

yes, 274... but the board i pulled the 274 out of had E B C on it, near the pads of the transistor

The E B C means...

E = Emitter
B = Base
C = Collector

. Then it may be a transistor (could be audio out, instead of the xistors in pic#1), but it was not unusual for there to be "weird" lead markings on old PCBs. . A schematic would be a BIG help.

I have no further information on this radio, how about a photo of the PCB?

. Probably won't do me much good, but it may help others. . Any model/serial/revision numbers may help. The Manufacturer's name may help.

PS: westfw or Goodhart may know what some of the components are. If they don't reply soon, PM them with a pointer to this topic.

everything that has BCE where it was on the board should be a transistor they can be used for a variety of stuff even without knowing the exact specs (the trial and error way) and i think if you solder them back to place you got a nice audio amplifier of atleast some 10 - 20 W RMS. enough power to feel some small vibrations in the room

ya, that's not really possible, i took out too many components, capacitors, transistors, the PSU. plus there are a bunch of plugs that connect various components, power, speakers, antenna, etc.... I do not have the plugs I was kind of hoping to build a new amp, from the components I salvaged

many components are not too critical in their exact value. for example in capacitors often anything of same external size (which means close enough in capacity) works. if you want the amp try to recover it as much as you can and power up ! the new amp is a circuit that in its basic variant included in the existing amp circuit. but the existing amp sure has extra filtering etc that improve sound quality you can use the transistors in a new amp by means of trial and error. find a circuit that uses transistors you think are close. put in the transistors here and see if they overheat. if yes add resistors etc. and so on they can also be used in free circuit like switching / dimming huge amount of LEDs / inverter (AA batteries powered CFL) etc

ehhh: capacitor the same size!?! You can have a 100uF capacitor and a 1uF capacitor be the same size, just different voltage rating.

youre right. i meant capacitors of about same voltage too however even then it usually works - just too silent or with noise depending on the direction of error in capacitor value

just find in inet with words like transistor amp. i dont have anything above that


9 years ago

They all look like transistors to me. Pictures 1 and 4 could be the same transistor (xxx274) in different power packages; this is pretty common. It's also pretty common to only put PART of a part number on components, if the other parts are unknown. That could make them 2n274s, or 2sc274s, or ... I couldn't find a datasheet for any of the likely candidates to compate. Likewise the tiny transistors I was better were something like MPAS012. Except that there doesn't seem to be any such thing. (that could make the small cans the same transistor in a different package too. they have the 012 marking as well.) Or I could be looking at the date code and guessing all wrong...

yeah, 4th pic looks like a regulator some of these components might be "house marked" so nothing will turn up on google

you can just experiment with them without much knowledge. if you use resistors and low voltage youre not likely to blast the transistor by wrong connection look how they were connected in the circuit to guess what entries are emitter collector and base. for example in normal NPN transistor : the entry that goes to earth directly or thru small resistor is likely to be emitter the entry that is connected to other stuff thru high-ohm resistors is likely to be base then the third entry is collector the 7001 (img 1) 012 (img 3) 7009 (img 4) seem to me like manufacture dates - XXth week of 1970. they have nothing to do with the component and should not be used as search terms in google

I would guess that the fourth picture shows 274, not 214.