High impedance window comparator (CB6091E)

General Electric suggests this circuit in a 1980s documentation. The operational of the time is FET-type input. Modern equivalents may be used.

| Clique na imagem para ampliar |

Power Transformer Test (CB21053E)
This test circuit for transformers connected to the power grid makes use of a variac. We found it in...
Mini Radio AM (CB20322E)
In this receiver the is formed by 80 turns of wire 28 or close in a ferrite rod. The handset is...
Phono amplifier (CB23747E)
This audio amplifier circuit was found in Radio Electronics magazine from June 1966. The circuit is a...