Univox

And a little clip with a small cap to tame the squeels and a LPB-1 with a trimmer at the output to fix the level issue. Your browser does not support this audio

Note the pin layout required for the transistors.  This will accommodate many modern NPN silicon transistors, but you will need to either alter the layout or twist over pins if using transistors with a different pin layout like the 2SC828s used in the original.  One for a 1590BB, but I’ll do a 1590B friendly version … Read more