In article ,
Syd Rumpo wrote:
On 08/11/2016 17:59, The Natural Philosopher wrote:
On 08/11/16 17:43, Syd Rumpo wrote:
On 08/11/2016 15:34, WeeBob wrote:
Hello.

I have an old wired doorbell that has an 18V DC power supply. The
actually transformer has been (I think) channelled into the wall, or
underfloor boards in the attic. i.e. hard to get to.

A new fancy doorbell requires connection to a 8V AC power supply.

Is there a simple way to do this? i.e. 18V DV in, 8V AC out?

Thanks.

There is no /simple/ way to convert. Best buy a transformer - it
seems that 8V AC is quite a common doorbell voltage. For something
that's connected to the mains and left unattended for years, I
wouldn't fiddle about.

https://www.amazon.co.uk/Friedland-D.../dp/B00EPESM2U



If the power so low enough and audio amplifier fed from a 50Hz
oscillator is one way.

Would you *seriously* fit that yourself rather than use a bell
transformer designed for continuous use?

Of course. He's a very clever electronics design engineer. I'm told. By
him. And his company went bankrupt.


It's not simple, not
certified, certainly not as reliable and awkward to explain to the
insurance company when the firemen have left.

Assuming the 18v supply can provide enough current - which is likely since
an electronic device is replacing a mechanical one (I guess) a simple
voltage regulator should do the job.


Cheers

--
*Virtual reality is its own reward *

Dave Plowman London SW
To e-mail, change noise into sound.