how to build a transistor tester

[sgmezei]

IT308

   1.   6, 96,      90
   2.   18, 141  123
   3.   10, 97,    87
   4.   10, 121   111
   5.   30, 156   126
   6.   27, 186   159
   7.   8, 88,       80
   8.   15, 121   106
   9.   10, 90,     80
   10.   26, 156   130
   11.   12, 107    95
   12.   9, 98,        89
   13.   20, 120    100
   14.   10,112     102
   15.   7, 92,        85
   16.   11, 108,    97
   17.   20, 133     113
   18.   18, 121     103
   19.   12, 95,      83
   20.   17,117      100
   21.   7, 97          90
   22.   13, 103     90
   23.   7, 114       107
   24.   5, 83         78
   25.   10, 112     102
   26.   5, 88         83
   27.   8, 111       103
   28.   7, 103       96
   29.   6, 77         71
   30.   16, 111     95
   31.   9, 84         75
   32.   19, 120     101
   33.   10, 103      93
   34.   9, 104        95
   35.   7, 82          75
   36.   13, 111      98
   37.   9, 90          81
   38.   6, 86          80
   39.   12, 107      95
   40.   6, 101        95

[Haberdasher]

So 40 out of 100?

[plesur]

It's like you're starting your own numbers station ...  

[sgmezei]

Yes 40 out of 100, I got tired of testing so I am taking a break for a few days. They sound great.

And no, no number station....hahaha

[Haberdasher]

What about the gt402e's?  do those sound good too?

[jimmybjj]

wow, you are getting lucky with those gains. My last batch of tranny's (100) didnt have 1 fuzz faceable transistor.

[sgmezei]

Alright here is what I have come up with for testing all of them so far.


https://docs.google.com/spreadsheet/ccc?key=0AiuJFraWqwPxdDdUNE5fdmRuSE95S28tc2p0ZlJ0VWc


Also, I have to correct myself. I got the 108's not the 308's

[sgmezei]

Some of the Russian germaniums have an internal "shunt" resistor that makes measuring the gain accurately very difficult. The big-ass GT404 trannies don't see to have them, but the smaller flying-saucer trannies usually do.

On the other hand, the Russian trannies are generally far more modern in manufacture than the "coveted" US/UK germanium units. As a result, they tend to have lower leakage and lower failure rates. At least in my experience, that is.

Is there a better way to test these type of transistors then? A more accurate way for our purposes?