Author Topic: Dimmer buzz  (Read 184 times)

Offline Jack Aman

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Dimmer buzz
« on: May 26, 2018, 10:26:35 AM »
I have a D1 on an end table.  The lamp on the end table, (and it's mate on the either end) is on a dimmer.  When the lights are on, the phone picks up a raspy buzz...not terrible--you can still talk--but just loud/present enough to be annoying and make me want to use another phone.  Turning off the lamps silences it.  Interestingly, touching or holding the metal body of the D1 also silences it.  (Ground?)  Can a permanent fix be put into place?  All my other D1's and B1's run on subsets...this one has an AE mini-network inside.  Works perfectly otherwise.

Offline AL_as_needed

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Re: Dimmer buzz
« Reply #1 on: May 26, 2018, 10:39:45 AM »
Thats an odd one. Is there something that is not grounding correctly with the lamp and causing the feed back? I'm not sure how the issue crosses from the lamp to the  phone as they do not directly share a common power source (unless they tie into a home PBX or xlink etc).
TWinbrook7

Offline HarrySmith

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Re: Dimmer buzz
« Reply #2 on: May 26, 2018, 11:15:48 AM »
I would check the ground on the lamps or the lamp circuit to start with.
Harry Smith
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Offline Jack Aman

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Re: Dimmer buzz
« Reply #3 on: May 26, 2018, 12:40:31 PM »
Further experimenting this AM...the buzz is there even with the D1 disconnected.  Therefore it's RF.  Further it seems to be the phone itself that's acting as the antenna, not the cord.

Offline Key2871

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Re: Dimmer buzz
« Reply #4 on: May 26, 2018, 01:14:03 PM »
Are they CFL's ? Those will cause a buzz in a radio with a weak signal, or an older telephone. You could try a filter cap in the phone and see if it helps any.

Offline AL_as_needed

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Re: Dimmer buzz
« Reply #5 on: May 26, 2018, 02:03:51 PM »
Thinking about this further, and thanks key2871 for jogging my memory...another possibility.

I had a similar buzzing/humming concerning a princess phone of mine. After much back and forth it ended up being the wall-wort transformer I used to power its lighted dial. When plugged in, the wall wort back fed some stray voltage through the hook-switch (of the princess) into the phone wiring through the whole house. The buzz could be heard on all my phones depending when in-call and there was silence (drove me nuts  ;D)
TWinbrook7

Offline Jack Aman

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Re: Dimmer buzz
« Reply #6 on: May 27, 2018, 08:53:34 AM »
The buzz is audible even with the phone disconnected from the house wiring, therefore it's RF from the Lutron dimmer itself, transmitted from the cords and wiring inside the lamps.  Going to try a different brand of dimmer and hope it's better shielded/filtered.  Thanks for all replies.

Offline Ktownphoneco

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Re: Dimmer buzz
« Reply #7 on: May 27, 2018, 09:47:06 AM »
FYI, in addition to dimmer units, in the event your using LED bulbs in your table lamps, both dimmable and non dimmable "LED" lights emit radio frequency waves.    As your probably aware, LED lights operate by going on and off faster than the human eye can detect.   Apparently from what I've been told,  the circuitry  inside that drives the LED's, creates the RF.    According to several companies that produce garage door openers, LED light bulbs installed either in, or close to, some garage door openers that use RF remote transmitters to open and close the door, will cause the units to malfunction, creating a situation where the garage door opener will open and close on it's own.
If your using the older incandescent bulbs in your table lamps, then disregard what I just typed.  :D

Jeff Lamb

Offline Jack Aman

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Re: Dimmer buzz
« Reply #8 on: May 27, 2018, 11:00:01 AM »
That's a good thought Jeff and thanks for it.  As I was trying to narrow this down, I tried incandescent bulbs (you're right...my "daily drivers" are Cree LED"S) and then tried NO bulbs.  Buzz present in the D-1's receiver even with the lamps not operating at all.  Definitely the source is the Lutron credenza dimmer.  It's replacement will be here today from the Source Of All Things (Amazon.)

Offline Ktownphoneco

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Re: Dimmer buzz
« Reply #9 on: May 27, 2018, 12:55:50 PM »
Jack   ....   That's good.  I'm glad it was what you suspected as the problem.   I've used Cree bulbs as well, and I've yet to detect any "RF" interference on an antique telephone, but I don't have any telephones sitting in close proximity to lamps with LED bulbs either.    Yes, if Amazon don't carry it, it's usually not worth mentioning.  ;D
Have a great day.

Jeff
   

Offline Jack Aman

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Re: Dimmer buzz
« Reply #10 on: May 28, 2018, 11:24:29 AM »
Epilogue:  I replaced my Lutron credenza dimmer with a Leviton unit.  The Leviton replacement dims better and while not completely silent in terms if putting "buzz" into the D1 that sits on my end table, it is easily 80-90 percent better.  The phone is comfortable to use again with only the faintest hum audible when the lights are on.  The Lutron introduced a raspy buzz that really made the phone unusable with the lights on.  Glad to have it solved.

Offline Key2871

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Re: Dimmer buzz
« Reply #11 on: May 28, 2018, 12:56:38 PM »
I used to work in electrical supply business, and I had several electricians come in and want leviton dimmers, only.
At one point I asked one guy, why? He said leviton were better with less problems than the lutron dimmers.
After a short time that's all we stocked.
All this brought back the memories of working there.