AC128 Fuzz pedal

152

01:41:01

Germanium transistor and diodes 

published 6 years ago

westelaudio

6 years ago

AC128 are crap and known to fail quite often. Sadly it's used in many great receivers etc. for quasi complementary pairs and the reason for their demise. They are probably getting rare. Bon't use this transistor on anything new.

westelaudio

6 years ago

I mean, at least matched pairs are getting rare. Would be nice if someone started to make them again but more reliable

giomix

6 years ago

Is possible find some ACxxx in internet yet, I have someone in my hobbyist laboratory. I use them only to repair some receivers of year '50

westelaudio

6 years ago

They were used up until the early 70s, mostly for complimentary output stages in low power radios but also in combination with AD149 or other big ones for Darlington/Sziklai output pairs in HiFi receivers. And for those applications you need matched pairs with AC127 or 176, otherwise it will not work correctly or even blow.

giomix

6 years ago

I agree with you 100%

westelaudio

6 years ago

I actually have a receiver needing a new pair right now, lol.

giomix

6 years ago

In the first OM receiver I built, perhaps a reflex or reaction type don't remember well, ( I was fourteen now unfortunately I'm near the 60 ... ) I used an ac188K, how much time ago!!!

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