Williams sys11 transistor testing

[48]

Getting ready to crank up my sys 11 game, reading on clays guide on dirty transistor testing, using a multimeter on continuity (buzz) to test to ground.
Thing is on my game there are around 30 transistors buzzing, can't see that many being bad.
Should I have removed some connectors off the cpu board or something? I feel I must be getting some feedback somewhere but damned if I know from what.
Anyone tried this? perhaps a tip or two or a point in the right direction.
BTW  no coils shorted, all test OK.
Cheers.

[ddstoys]

Unalaska test my tip102 with the black mm lead on the metal tab and the red on either side leg you should see between .4 and .6v on each outside leg.  Not 100% but almost.   I've found the dirty test to buzz even in good transistors

[Retropin]

I find Clays transistor testing to be pretty hit and miss.

Best way i do is with an anologue and read the sweep... Base to collector - lo one way high the other
 Base to Emitter - Lo one way Hi the other

Emitter to Collector should always be High either way round.

You dont need to know which is which to do this.. just swap leads at each reading.


This way is about 99% accurate for in cct i find

[48]

Thanks Daniel and Retro,
Didn't think it was right, was looking for a quick way out.. 
As usual, ends up taking longer using a short-cut!

[FirePower]

... reading on clays guide on dirty transistor testing, using a multimeter on continuity (buzz) to test to ground.
Cheers.

Lindsay does your meter have a diode test function? You might have a look at this as well, it is a test that measures the forward voltage drop of the junction which should be about 0.4 to 0.6V for a silicon based junction.

[48]

Actually I do have one with a diode test, going to hook into this thing tonight hopefully.
Thanks David.

[ddstoys]

Sorry Lindsay i did foget to add set your multi meer to diode function

[48]

Thats fine Daniel, good news is they all seem OK  God there are a lot of them though......