Off line Telephone tester

Posted on Feb 7, 2014

Off line Telephone tester. Here is a circuit of an off-line telephone tester which does not require any telephone line for testing a telephone instrument. The circuit is so simple that.

Off line Telephone tester
Click here to download the full size of the above Circuit.

Leave Comment

characters left:

New Circuits



Popular Circuits

0-50V 2A Bench power supply circuit and explanation
Expandable Graphic Equaliser
pic RN-41 bluetooth module not transmitting data
inductance meter adapter circuit
simple gauss detection switch
interfacing ultrasonic distance sensor ascii pic microcontroller
Brightness display circuit 555
Five sections of the spectrum display circuit
SE9518 holiday lights ASIC
Press light switch double circuit 3