Code Sidetone Generator (CB26323E)

This code practice circuit was found in a 1990s issue of Radio Amaterur Today magazine. It produces an audio tone with the 555.

| Clique na imagem para ampliar |

Digital voltmeter 7107 (CB25985E)
The figure shows the basic way to use a 7107, a 3 and ½ digit converter in a digital voltmeter. The way...
Long-Range Wiretapping (CB19321E)
We found this wiretapping circuit in a publication from the 90s. The circuit allows the cable...
Light Meter (CB5306E)
This circuit is from the 80s own LM10 manual. The circuit can be implemented with other...