[BakeliteBear]

Firstly - thanks for all your help.

I have had a play and have created my version of the rectifier as shown in the image. I don't have any originals to compare with, but it seems to be OK.

I would like some help with the electronics here though. My diode theory is v.poor and I am not really clear how they operate in the circuit. Can anyone help?

Also various people I have spoken to, have quite contradictory views as to whether fitting them in 200 and 300 series telephones is necessary or desirable. Indeed, one dealer I know takes then out of the 700 series telephones.

I have been told the following.

1. They are quite unnecessary in the 200 and 300s and that if the dial contacts are clean and the telephone wired correctly there should be no extraneous noise.

2. Fitting the diodes can have a detrimental effect on speech volume.

3. They should be fitted to 300s, but not 200s – although one of my friends tells me that they always fit them in 200s without bellsets.

Can anyone offer some clarity to this fog??