5-tube commercial radio (T1619E)

This commercial superheterodyne receiver was found in a 1949 Radio Electronics. The circuit uses battery.

LED Binary Counter (CB4345E)
This circuit came out in an American magazine that no longer exists. It's the Electronic...
Code Switch (CB10287E)
This circuit originally came out in a Budget Electronics from 1981. The American magazine no...
LM382 Preamplifier (CB15083E)
This is the traditional audio preamp configuration with the National Semiconductor LM382. The...