Forum Home
PC World Chat
 
Thread ID: 123127 2012-02-05 07:26:00 SParkies, old P&T techs, anyone brighter than me ... Wiring Up A Bell Ringer Murray P (44) PC World Chat
Post ID Timestamp Content User
1257525 2012-02-05 21:43:00 Looks just like a bell in its own right and I seem to remember 18v. mikebartnz (21)
1257526 2012-02-05 21:44:00 Cheers B.M. and Dugimodo. I haven't managed to track an old P&T or BT spec or schematic, hence my post here and not that I'm particularly good at interpreting those things ...

But from the sounds of it, if I/my electrician patch in to a nearby light circuit with a close-ish power pack/transformer form Jaycar or like, we should be sweet. The fun will be isolating the bell push... unless I go for mechanically isolating the outside push from the inside switch, thinking aloud.
Murray P (44)
1257527 2012-02-05 21:46:00 Looks just like a bell in its own right and I seem to remember 18v.

Cat amongst the pigeons, Mike, you may well be right. It does look like a shop/factory type ringer.

How would I test it, I have a wee multimeter (once I replace the battery)
Murray P (44)
1257528 2012-02-05 22:00:00 That looks similar to the ringer / doorbell we had at the old flat. It was 8v. The transformer for it was screwed near the main powerboard in the flat

Tell me young man, how stealthy are you?
Murray P (44)
1257529 2012-02-05 22:03:00 Ahhh, then you'll need a ringer to drive the bells. HERE (www.kapiticoastmuseum.org) ;) B.M. (505)
1257530 2012-02-05 22:47:00 Quasimodo was a good bell ringer. Didn't need 'wiring up' either. Richard (739)
1257531 2012-02-05 23:27:00 How would I test it, I have a wee multimeter (once I replace the battery)
Still learning that type of thing. Have just rewired an old phone charger wall wart and am going to get a guy to test it to make sure I got it right rather than blow a $55 Arduino.
mikebartnz (21)
1257532 2012-02-06 00:11:00 The Ideal thing would be to find someone with a adjustable bench top AC power supply and just crank the voltage up until it starts ringing properly :)
I dunno if it will handle 50hz well so the frequency could be the biggest issue, if it does that little hammer will be going back and forth like Quasi on crack.
dugimodo (138)
1257533 2012-02-06 00:25:00 By the way assuming those coils are in series, and I think they will be, that gives you a 1k load so just divide your voltage by 1k to find out the current draw I=V/R simple ohms law, ignoring impedance and such it'll be fairly close.
So if you feed it 12V it'll use 12mA and 50V will use 50mA, not a huge amount so fairly safe to experiment with. See if you can find an AC plugpack to try.

worst case would be parallel which would make the load 250 ohms and increase the current to 48ma @ 12v and 200mA @ 50V so still not much
dugimodo (138)
1257534 2012-02-06 00:58:00 By the way assuming those coils are in series, and I think they will be, that gives you a 1k load so just divide your voltage by 1k to find out the current draw I=V/R simple ohms law, ignoring impedance and such it'll be fairly close.
So if you feed it 12V it'll use 12mA and 50V will use 50mA, not a huge amount so fairly safe to experiment with. See if you can find an AC plugpack to try.

worst case would be parallel which would make the load 250 ohms and increase the current to 48ma @ 12v and 200mA @ 50V so still not much

Unless I'm misinterpreting the photo attached to the OP, each coil has 500 ohms printed on it?
Murray P (44)
1 2 3