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Vintage threads from the first ten years

Re: Big MUff

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6/17/1997 11:01 PM
Mark Hammer	Re: Big MUff Um, far be it for me to interrupt a good mystery, but do we actually KNOW that the e's, b's, and c's are where we believe them to be here? Have you pulled one of the BC239's out and stuck it into a transistor socket on your DMM to corroborate the assumed pinout. I'm not doubting anyone's competence here, merely the ability of manufacturers to stick to a standard!

6/18/1997 8:10 AM
R.G. Keen	Amen.

6/18/1997 12:53 PM
Paradiddle	Does anyone know the pinout for this transistor? Also i have the schmatic scanned if anyone wants it,....... Jeff

6/18/1997 10:54 AM
R.G. Keen	I forgot to mention - I just got a batch of BC239's in, I'll test the pinout and find out for sure - at least for the manufacturer I have. My experience is that all parts of a given type number will have the same pinout. Unfortunately, that is not necessarily true about DATA BOOKS describing pinouts for a given device...

6/18/1997 12:55 PM
Paradiddle	Thanks,......do you still want the schematic I drew up? Jeff

6/18/1997 5:20 PM
R.G. Keen	Schematic? Yes, please. email it to me as a file attached to the email if you can. That makes it easier to retrieve it.

6/21/1997 5:59 PM

Re: Big MUff>>Read for info!

I took a look at the schematic you drew, and although I didn't compare every part, it looks like if you swapped each collector for emitter, it would be a pretty fair match for the schematic I've seen. There are some component differences, but EH was infamous for sending techs out to surplus places for bags of the closest component they could find when they ran low on something.

I think this is most likely a simple pinout difference on the package, at least until I can do a component-by-component compare.

As a reliable guide, the most positive pin on an NPN is the collector, next is base, and least positive is the emitter. This is true for all situations except where the transistor is in hard saturation, or is deliberately not being used as an amplifier. (these look like they are)

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