This circuit is from a 1980s Motorola documentation. The circuit can be made with modern equivalent components. The original circuit is for the 115 Vac (110 V) grid and has two settings.
We found this circuit in an old documentation for hams. In it we have the way to use a varicap to...
Found in an 80's documentation this circuit uses an integrated from the uncommon era today. Other...
This circuit is stabilized by a thermistor or NTC with a resistance between 2 and 5k. The signal is...