Bike speedometer (CB20497E)

This circuit can be powered by a solar cell. The circuit is from a 1991 documentation having a phototransistor as sensor.

Cascode Stage with FET (CB4189E)
This circuit was found in an old 1980s valve documentation. The circuit can directly replace a...
Bargraph Indicator (CB5177E)
This circuit is from an 80's component manual. However, the circuit may be of a modern equivalent...
VCO and Frequency Comparator (CB21051E)
Found in an Electronic Design from the 90s, this circuit makes use of a PLL CMOS. Values for...