Found in American documentation from the 1980s, this circuit has a diode feedback. At the exit we have an indicator LED. The LM3900 is a transconductance operational amplifier.
This converter was found in the June 1991 issue of Radio Electronics magazine. The circuit uses...
This simple field strength meter was found in a 1970 publication. The zero-adjustment...
Found in Philips' 1968 documentation, this circuit serves as a 6.3 V reference for high stability. |...