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[email protected] jurb6006@gmail.com is offline
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Default Scopes, Horizontal Deflection

Thanks. I actually just checked it real quick with the scope but did not pay alot of attention to the DC levels. I actually don't even know the pinout yet.

But I got square waves on one pin the the on/off time varies with the ten turn pot on the front panel for delay. That puts the problem right there, I should be able to smell it.

If the circuit works they way I think, which is they are feeding the emitter of Q4565, I do not like that. I mean I think it is bad because of the readings, but I think it went bad because of the way they used it.

But really, they probably had no other choice. I have seen it before, I have done failure mode analysis. And I have found that at times, they simply had no other choice and their circuit was going to beat on this certain part.

So anyway, what to put in there. I am not going to pay eBay $37 for a 11132-0002-1005 transistor, even if it is in original packaging. (I made the number up so don't bother)

It is pretty much a common base amp, but not really used linear, I THINK. No, I am pretty sure. You see the base hard biased by the two 1K resistors making the base voltage -4 volts. And it says right there that -3 volts starts B sweep.