I haven't tried the Animato yet but when it comes to germanium transistors I tend not to worry about parts numbers, gains and leakage is more important IMHO. The germanium transistors in this circuit forms a "Sziklai pair" (https://en.wikipedia.org/wiki/Complementary_feedback_pair) which usually works best with low gain and very low leakage transistors. Hfe 40 to 60 is usually well enough.
I left a comment the other day but I don’t think it went through. Built this using AC127 and 128 germaniums for Q1/Q2 and 2N5088 for Q3 - Q7. I had no gain but I flipped Q2 and it solved that problem. I turned the 10k trim pot up very little. This thing is a BEAST! Love it. Works great. You can tag this one. Thanks for this layout. Another fine job Sir. Matt
Could I use an AC128 pnp and a 2n1308 npn in this and have it sound good? Has anyone tried these in the Animato
ReplyDeleteI haven't tried the Animato yet but when it comes to germanium transistors I tend not to worry about parts numbers, gains and leakage is more important IMHO.
ReplyDeleteThe germanium transistors in this circuit forms a "Sziklai pair" (https://en.wikipedia.org/wiki/Complementary_feedback_pair) which usually works best with low gain and very low leakage transistors. Hfe 40 to 60 is usually well enough.
I left a comment the other day but I don’t think it went through.
ReplyDeleteBuilt this using AC127 and 128 germaniums for Q1/Q2 and 2N5088 for Q3 - Q7.
I had no gain but I flipped Q2 and it solved that problem. I turned the 10k trim pot up very little. This thing is a BEAST!
Love it. Works great. You can tag this one. Thanks for this layout. Another fine job Sir.
Matt
Also the AC127 / 128 had hfe of 50 to 65
DeleteExcellent! Will tag it and thanks for the transistor info.
Delete