Quote:
Originally Posted by bigus01
'There is a small voltage of about 2.5v across T5 & T6 with handset off the hook.'
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There should be no d.c. voltage across the receiver. There's a couple of reasons why you may be seeing it.
Have you got another, more modern telephone plugged in elsewhere, or is there something else across the line you're using for your testing?
Can you disconnect your telephone from the line, disconnect the handset from the telephone terminal block and measure the resistance from terminal T1 of the
dial terminal block to terminal T5 of the
telephone terminal block? The only resistance you should measure is the 35 Ohms of the ASTIC winding.
With the handset disconnected and the carbon mic in place, can you measure the resistance of handset wires green - red and green - white?
Out of interest, can you see the numbered connections on the ASTIC (induction coil)?