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General discussion

How to connect an old tel. bell to door bell.

Sep 19, 2012 5:27AM PDT

Hi,
I have an old Telefone very loud Bell & want to connect it to the gate small bell (which i cannot hear).

I wish I could attach a foto here, but it has 2 2" bells, silvery cylinder el. component 3" long, 2 electromagnets 2" long & 10 screw connectors for wires.

It used to work untill a disconnected it & now use cordless telefone.

Does anybody have a cristall ball to see it & advise if I can use it as a gate bell? .....thanx ......nick

Discussion is locked

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FUN PROJECT!!!
Sep 19, 2012 5:36AM PDT

The problem here is that we have a few issues to solve. The first is understanding that the really old ringers required a signal from the telephone company so let's find out what that signal was. (I'm going to use duckduckgo instead of google here.)

http://duckduckgo.com/?q=telephone+ring+signal+specifications

AHA, we find out it matters what COUNTRY this Telephone is from. You spelled it as "Telefone" so for this discussion you'll have to use your country's specs. For the USA I read at http://www.epanorama.net/circuits/telephone_ringer.html that it's "20Hz minimum ring voltage supplied is 40Vrms (delivered into a 5 REN load)."

Now that we know this we have to find a way to create such a signal. Again, we duckduckgo.com as above to find this link. http://www.techlib.com/electronics/telephone.html

The second schematic is what we need. Now try connecting your wires from your current bell to that ring inhibit and see if that works for you.
Bob

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How to connect an old tel. bell to door bell
Sep 19, 2012 5:43AM PDT
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And it looks like you need to build the circuit to drive it.
Sep 19, 2012 5:49AM PDT

Since most AC or MAINS is 60Hz and these bells need 20Hz (varies on country) then you are looking at a small electronics project.
Bob

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How to connect an old tel. bell to door bell
Sep 19, 2012 6:22PM PDT

Sorry for the shortcut "....fone", it is here in the old UK BT.

Did you see the attached foto of it?

Could'nt make a word of all that but the duck was fine.

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Saw the foto
Sep 20, 2012 12:57AM PDT

And it sounds like a fun project. The links I gave have the necessary details but I can imagine those that don't make their own stuff may feel challenged.
Bob

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How to connect an old tel. bell to door bell
Sep 20, 2012 4:01AM PDT

OK thanx all, can never manage it, will sell it !!!???