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Old 18th Sep 2017, 11:55 pm   #17
russell_w_b
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Default Re: REN, Resistors &c.

Quote:
Originally Posted by ThePillenwerfer View Post

Doesn't setting the volume to 'Off' short the whole thing thereby rendering all bells mute?
The ringer still draws the same current and has the same voltage dropped across the 'bell' wires (T4 and T16) irrespective of whether the switch is off or loud, so I'm presuming it makes no difference (well, OK... There's a couple of milliamperes difference, but that's all. ).

Looking at the graph I plotted re: current versus voltage and thinking about it, I suspect the design brief was for a 1000 Ohm 'ringer' which would draw 20.4mA with the series capacitor on a 75V ringing supply at the premises.
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