This circuit is used in VHF and UHF superheterodyne receivers. The circuit is from the 1964 RCA transistors manual. Equivalent transistors such as the BF495 can be used.
Found in an Electronic Design from the 80's, this circuit monitors the charge of a 12 V battery....
Found in an EEE from 1970, this circuit supplies a voltage of 12 V DC x 10 mA current from the...
Using old germanium transistors like the CK722, this circuit has good gain. We found it in a...