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trying to amplify wireless doorbell with guitar amp

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Big Sammy

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My father is deaf without his hearing aids, and wants me to amplify the wireless doorbell so he can hear it at night. I thought the easiest way would be to run a patch cord from the wires in the doorbell unit out to a small practice guitar amp. I did this, but I just get a loud hum. When the doorbell is pushed, I can hear it, but the hum is way too loud. Is this caused by the "noise" in the household current that the wireless system is plugged into? How can I solve this problem? Help!!!
Thanks,
(the doorbell unit is 120V AC, 60 Hz, 0.06A) I don't know if this helps, but it can't hurt!
 
Does the doorbell make ding-dong tones through a speaker?
Is the doorbell circuit safe with a power transformer?
Connect shielded audio cable to the speaker in the doorbell and to the input and ground of the amplifier. The shield of the cable is the circuit ground at both ends.
 
Without actually seeing the receiving end and how it is configured it is real hard to say. Sounds like the amp is picking up 60Hz hum (noise) from the AC. This would explain the buzz you hear. Pictures of the receiving end would help, anything so people can get an idea of how this particular system works.

I can honestly say been there and done that with my father-in-law up to and including using a flashing lamp with the telephone system.

Ron
 
What I am trying to use is a guitar cord, with one end cut off. It has a jack at the other end that will plug into the input of the amplifier. The cord has a coated wire, surrounded by copper wire and there looks to be some sort of foil there as well. What do I connect to the speaker so the sound will travel down the cord to the amp? Just the coated wire? How do I ground it?
Thanks....
 
The "coated" wire is probably the insulated center wire that carries the signal.
The surroundong copper wire and foil are the shield that connects to the signal ground at both ends.

If you do not know which wire on the doorbell speaker is the ground then try it both ways.
 
If the receiver uses a speaker, then the best way would be to use the signal to the speaker directly into the amp input. That is pure speculation and winging it. The speaker could be a piezo speaker which is a different animal. The approach you are describing likely won't work for several reasons, among them getting a guitar string to pick up the audio.

Ron
 
Guitar string? No...I have a guitar cord which has an input male jack on both ends. One end ususally plugs into guitar, the other end into the amp. I have cut one male end off and want to wire that to the chime speaker. The other end I want to plug into the amp, which I am hoping will amplify the tone from the door chime.....but when I turn the amp on, I get a loud humming.....how can I wire this so that there is no hum, but the chime is amplified louder? the chime (it is a new wireless one) plugs into an outlet.
 
OK, now I much better understand. Trying to picture it I was like what is he doing. Maybe I should open a beer.

You can try and I say try placing the leads across the speaker connections. If you get the hum try reversing the leads. Door chime systems can vary so much it is hard to call. I haven't a clue what type circuit is driving the speaker. If you reverse the leads across the speaker and you still get the hum this won't be all that simple. We don't even have a clue what is driving the speaker and what signal level it actually is. Sort of walking blind if you will.

Ron
 
And the speaker says "KB 100 ohm 0.1W RONS" on the back....(just trying to provide as much info as possible...don't know if it helps)
 
Have you tried just placing the amp input across the speaker? Then if a hum reversing the leads across the speaker? The guy good at this stuff is AG who hopefully will return with something to add that I am missing.

Ron
 
I am worried that the cheap wireless doorbell has no power transformer then has the speaker connected directly to 120VAC or earth depending on its power plug. I do not want it to cause the chassis of the amplifier to be 120VAC.
 
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