Telephone-tap


Posted on Aug 9, 2012

Amplify or record a telephone call with the simple circuit shown. The 8-0 secondary winding of a miniature transistor output transformer is connected in series with either of the telephone lines.


Telephone-tap
Click here to download the full size of the above Circuit.

The 1000-0 primary winding can feed either a cassette recorder or an audio amplifier.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

Motor speed controller with timer 555
Visual zero-beat indicator
Variable-Frequency Audio Bp Filter Circuit
Charge amplifier
TC35I use wireless data transmission and GSM communication module circuit design schematics



Top