Re: Matched Transistors
When I was a teenager I built a transistor tester for all those bags of mixed parts.
It is still in my workshop.
Collector currant was originally set with fixed resistors with 5 values between 2ma and 100ma with fixed VCE.
It was originally accompanied by a set of log tables and later a calculator to divide collector current by the measured base current to get the HFE.
A bench power supply has since been added to get many more collector current settings going as high as 2 amps for big power transistors.
It was effectively a 1970s teenagers curve tracer but it is still useful.
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