This audible continuity test was obtained in a book from the 90's describing simple projects. The feeding is done with a single battery.
Analog Devices/Hittite's HMC3653LP3BE HBT Gain Block MMIC Amplifier covers 7GHz to 15GHz and is...
This circuit was suggested by Motorola's 1993 Linear Interface ICs. Equivalent operational amplifiers...
Indicated to be used at the sensor input of a PC, this circuit was found in an English...