Wattmeter (T1351E)

This circuit is from a February 1949 Radio Electronics magazine. The circuit uses 3 tubes and includes the power supply.

Pressure or Beat Sensor (CB11516E)
This circuit was obtained in a Popular Electronics of 1991. The magazine no longer exists, but the...
5 V x 4 A power supply (CB1155E )
With this voltage regulator we can have currents up to 4 A at a 5 V output for TTL circuit power. The...
Biofeedback Thermometer (CB24401E)
This circuit was found in February 1976, Radio Electronics magazine. The circuit is quite...