This 100 MHz bridge circuit was found in an American 1970s documentation. The supply voltages are not indicated, nor are the tubes.
This configuration can be found in other articles on this site. This is from European...
This 18 V x 300 mA power supply was found in a 1969 documentation. The integrated circuit is...
This experimental 555 circuit sends signals in the medium wave band to a receiver a few meters away....