Saturday, December 24, 2011

Tinkering on Chrismas eve

Yesterday I tinkered with some vintage germanium transistors. I chased my tail for hours trying to figure out why the distortion was so bad on the audio I was trying to amplify! Not to mention that the gain was miserably small...

With lots of reading I have come to the conclusion, that the main reason you would ever want to tinker with vintage germanium transistors is to reproduce the distortion effects of "that era".

I set about measuring the Beta on them, they vary so much across the same model!

The AX9000 run from a Beta of 19 up to 36! The ACY21 vary from 70 up to 150! So getting a balanced pair out of these is a bit more difficult that I was expecting.

I might just put these back in their box and tinker with some "modern" silicon transistors, that date to the early 1970's. I picked them up last year at the AHARS HAM radio buy'n'sell here in Adelaide. This year I picked up some old school headphones and a 1960's microphone.