identifying transistor

What is the circuit? Is it a critical application? Any NPN might work depending on the voltages and current. Again gain depends on their application Frank

I don't have a schematic, it's an old VHF transceiver board that I wanted to debug. I don't even have the transceiver shell to identify it. Of course if I had a schematic I could guess better.

Thanks Frank IZ8DWF

what sort of date ?

on the board it is printed 19 MAI 1982, looks like a date in some language.

Regards Frank IZ8DWF

If it is a Motorola radio, it is a house number. You would have to talk to a Motorola two way radio shop and give them the assembly number to figure out what radio it is from. The information was never made public.

Looks as though you'll have to desolder that other one and measure the gain at different f and repeated with some added pF, and if darying try and find Vc and Ic max or at least some minimum values from the circuit their in

-- Diverse Devices, Southampton, England electronic hints and repair briefs , schematics/manuals list on

Frank, I used to work at a Motorola 2-way FM radio service shop (back in the 70s). Many of their semiconductors were marked in this fashion, but the real device number was preceded by an "M"; thus, making the transistor number M9570. Search the NTE reference for a cross and see if it matches with what you know about it.

Cheers!!

On 09 Oct 2009 08:56:37 GMT, frank put finger to keyboard and composed:

It crosses to the following:

- Franc Zabkar

Thank you very much! It looks like a common part will fit in its place though.

Now I have to find a JFET replacement for a custom HP part, but that's another story... I'll dig on my HP parts units first.

Best regards

Francesco