This is a 1946 post-war model radio. The 3-tube receiver has a long-known tube configuration.
This fixed current source uses a Norton LM3900 amplifier. The maximum current depends on the...
This circuit was found in a 1973 publication. The SCR may be the TIC106 and must use a heat sink,...
This circuit was published in a 90s Radio Electronics. The circuit uses the well-known LM386 that...