CB935 switchboard

[ricksteptoe]

Hoping someone can help.
I've just got one of these and am a bit confused re the connections, as there are only two terminals for the exchange line would they be connected to 2 and 5 in the BT socket, and if so, does it matter which way round?
Next, what voltage would the power supply be, I have seen reference to a 12 volt supply, but the N diagrams don't give a voltage?
Finally, what modifications would I need to make to extension phones?, should the white and green cords be commoned to make them two connection and can any series phones be used?
Sorry if i've used the wrong terminology but only recently into period phones.

Rick

[JohnBHanson]

I think about 10 volts or so would be ok. Line to be connected to pins 2/5 on BT socket (or via asdl filter).

Phone connections are for A+B wires, connections depend on the phone. To use modern phones use a master socket and connect to pins 2 and 5.

Hope that helps and enjoy.
Which period phones are you looking at (N diagram connect as for a phone line to A+B of the extension).

[Dave Moll]

For plug-in extensions from a CB935, I tend to connect the extension pairs to BT master sockets. That way, the 'phones themselves may use either their internal ringing capacitor or that in the socket, depending on how they are wired.

When connecting an old 'phone directly, just make sure it hasn't been converted to three-wire operation (i.e. its ringing capacitor is still in circuit).

I run them from 12 volts (either 2x996 lantern battery or 8xC cell in suitable holders). Either arrangement can be fitted neatly inside the cabinet if desired.

[ricksteptoe]

Thanks for the replies. I'm planning to use 232s and 332s, presumably the 232s would each require their own bellboxes. I am still not clear on the actual wiring of the termination block, for instance my 332 has the standard three core cord in red, green and white, so would I parallel the green and white together for one contact and red for the other, This is for a hard wired system with onlt the switchboard plugging in to a bt style socket. I've been collecting odd bits for years and am finally in a situation where I can put them to use.

Hope I have explained adequately!

Rick.

[Dave Moll]

If your 332 has its internal capacitor correctly wired (as per diagram N432), you should be able to ignore the green wire altogether - this would only have been used in such setups as a series-connected extension bell, earth for shared-line working, etc.

[ricksteptoe]

Thanks Dave,
now comes the boring bit, putting in the hard wiring!

Regards,

Rick.