We found this circuit in a 73, magazine for radio amateurs of the 90s. The circuit is passive and most telecommunications receivers can be added.
This circuit was found in Philips documentation from 1965. No information was given about the...
This sophisticated decade of benchtop resistors was found in the November 1989 issue of Radio...
This configuration based on a conventional astable multivibrator was found in a 1982 publication. The...