Re: AVO TT169 Transistor Tester
Sunning Up - thought I'd do a wee comparison test with more advanced transistor testers, even though the TT169 is merely an in-circuit tester. Used a 2GT182 Ga PNP (OC71 eq.).
1968 Mullard Data Book says expected hFE of 41
1968 AVO Tr. Data Manual says typical beta of 47
1996 TITS says hFE of 30
Results :- CT446 Mk2, beta = 64
1950's Sienens Ediswan Type R2285, alpha dash/beta = 54
1980ish Kamoden HM350, hFE = 30
DAC55, hFE = 48
Chinko/AVO Homebrew tester, hFE = 62
And the TT169 starts to flash at 1.5 on the control knob. Obviously this is just an arbitrary indication.
Both the DAC55 & the CT446 just showed a few tens of uA leakage.
Conclusion - just a handy reliable wee in-circuit go/no-go tester. But the probes are a bit awkward to use.
Regards, David
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