This 80's General Electric circuit is guarded by the noise-guard for operating current. The circuit has an input sensitivity of 3 pA. The font must be symmetrical.
This circuit was found in Motorola documentation from 1966. The lamps are according to power and...
This circuit, which uses components still common today, was found in a 1997 documentation. It...
This circuit is intended to apply the music signal from a stereo to a telephone line for the...