We found this circuit in a Radio Electronics from February 1966. The transistor is from the time and so are the transformers. The circuit is battery powered. Observe the impedances.
Written in an article in Radio Electronics magazine in April 1987, this circuit triggers an alarm...
This is the receiver circuit for the previous transmitter. The circuit has a programming key to...
This is an example of a temperature sensor shield using the Texas Instruments TMP390 obtained from...