This circuit was found in an ancient American documentation. With it is possible to double the frequency of a transmitter For the range of 6 meters obtaining 8 W. The circuit makes use of varicap.
In the figure we show how to supply a DC motor from 6 to 12 V with alternating current. The diodes...
This circuit was obtained in a 90’s documentation. The operational amplifiers are from that time....
When the remote connection is disconnected or interrupted, the lamp will come on. The transistors can be...