This switched filter was found in the 1969 documentation. The FET should be current-matched and eventually equipped with a heat sink.
The 4028 CMOS IC not only contains the complete decade counter, but also the 7-segment decoder...
If the reader is skilled, he can mount this spy micro-transmitter with SMD components and obtain an...
This negative bias circuit provides negative voltages from 3.5 to 6.5 V sources. The circuit was...