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TonyDuell · 7th Feb 2023, 4:58 pm

With the telephone unplugged, set your multimeter to a resistance range that covers 1KOhms (probably marked 'Ohms * 100' or 'Ohms * 1K' on the selector dial). Put one probe on T4 and the other on T16. What resistance do you measure? Does the meter needle move at all?

The 2 bell coils are connected in series. One pink wire goes to one end of one of the coils. There is a connection from the other end of that coil to one end of the other coil. And the final end of 'the other coil' goes to the other pink wire.

I seem to remember there are 2 versions of the Telephone 706 Mk2. In one of them the connection between the coils is made by a wire connected to the coils. In the other, it's made by having one tag from each coil soldered to the circuit board, there is a copper track on the board that links them.

The 706 Mk2 is actually one of the easiest telephones to take apart, and a good 'first project' as a result. It's some time since I've done one, but I think you can loosen (not totally remove) the short screw at the top of the dial mounting (you put the screwdriver in from the side of the telephone) and then unhook the complete dial unit. It's still connected to the circuit board by 5 wires. Then one (? maybe 2) screws come out and the entire circuit board assembly lifts out leaving just the bell gongs attacted to the baseplate of the telephone.

7th Feb 2023, 4:58 pm	#25
TonyDuell Dekatron Join Date: Jun 2015 Location: Biggin Hill, London, UK. Posts: 5,209	Re: Vintage 706L not ringing With the telephone unplugged, set your multimeter to a resistance range that covers 1KOhms (probably marked 'Ohms * 100' or 'Ohms * 1K' on the selector dial). Put one probe on T4 and the other on T16. What resistance do you measure? Does the meter needle move at all? The 2 bell coils are connected in series. One pink wire goes to one end of one of the coils. There is a connection from the other end of that coil to one end of the other coil. And the final end of 'the other coil' goes to the other pink wire. I seem to remember there are 2 versions of the Telephone 706 Mk2. In one of them the connection between the coils is made by a wire connected to the coils. In the other, it's made by having one tag from each coil soldered to the circuit board, there is a copper track on the board that links them. The 706 Mk2 is actually one of the easiest telephones to take apart, and a good 'first project' as a result. It's some time since I've done one, but I think you can loosen (not totally remove) the short screw at the top of the dial mounting (you put the screwdriver in from the side of the telephone) and then unhook the complete dial unit. It's still connected to the circuit board by 5 wires. Then one (? maybe 2) screws come out and the entire circuit board assembly lifts out leaving just the bell gongs attacted to the baseplate of the telephone.