FAKE TRANSISTORS (CB or QRP type finals).. testing being done by Earl Andrews VE3AB.. to make
sure I don't end up using (or selling) bum transistors. New Articles just being written 22 December
2013. This article is not finished yet..neither is my testing! I will be doing much more on this topic in
the next few days and weeks ahead.
PAGE TWO of this article on testing for FAKES and
I could not find an old 2sc1969 in my collection of parts but I found an equivilant..an old NEC C1307. At least..I think it is an older transistor from an estate sale or
something as there were 3 of them labelled in a small plastic bag. I buy parts over the internet (ebay mainly) but I also buy older parts from ham radio flea
markets and collectors/hobbyists who are selling off their parts. -- Actually..I'd rather have the old parts than the newer ones for obvious reasons ..now !!!
To make a long story a bit shorter. I tested all the C1969s (2sc1969s) -- I had bought a lot of 21 on ebay..and they all worked with full RF output (1 watt full
scale) with the drive level ..kept about the same. ONLY ONE of the C1969s did not pass. It had zero RF output. So I did another test on it using my
transistor tester. See pics below.
The defective transistor ..marked with RED pen..measured as a diode when tested. So..looks like one of the junctions is bad. So..I am happy thus far with the batch of
2sc1969s. They seem to work well..(at least on 7.050 mhz). Im going to run through them again but on 28 mhz and see if they hold up to full or near full output when the
frequency goes up.
Thats it for now..Merry Christmas.. 73 Earl VE3AB

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(they are mirror sites)..established 2005 by Earl Andrews VE3AB