buzzing noise from elec clock

SS

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Aug 30, 2011, 3:22:49 PM8/30/11

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I use a cheapo electric alarm clock/radio, I also have a touch type
bedlight. Both require to be plugged into an extension as too far from
socket.
When both are plugged in the alarm gives a low annoying buzz, but stops if I
unplug the lamp.
Any ideas on how to stop the buzzing.
thanks

John Williamson

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Aug 30, 2011, 3:31:42 PM8/30/11

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First try running the lamp via a second extension lead, and if that
doesn't help, try moving the lamp about the same distance again away
from the radio.

It seems the electronics in the lamp are transmitting interference
either along the cable or through free space.
--
Tciao for Now!

John.

Frank Erskine

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Aug 30, 2011, 4:10:24 PM8/30/11

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On Tue, 30 Aug 2011 20:22:49 +0100, "SS" <none...@blueyonder.co.uk>
wrote:

Err - unplug the lamp.

HTH -
--
Frank Erskine

Andy Burns

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Aug 30, 2011, 4:37:16 PM8/30/11

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John Williamson wrote:

> SS wrote:
>
>> I use a cheapo electric alarm clock/radio, I also have a touch type

>> bedlight. When both are plugged in the alarm gives a low annoying
>> buzz
>

> It seems the electronics in the lamp are transmitting interference
> either along the cable or through free space.

It's not unknown for the radio's aerial to be within the mains flex
where the earth conductor isn't.

SS

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Aug 30, 2011, 7:07:15 PM8/30/11

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"Frank Erskine" <frank....@btinternet.com> wrote in message
news:ksgq575ijbvqqv7n2...@4ax.com...

Maybe I should have mentioned I want to keep both plugged in. :-)

Brian Gaff

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Aug 31, 2011, 4:01:38 AM8/31/11

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Is this a lamp with a transformer or switch mode psu in it by any chance?

Brian

--
Brian Gaff - bri...@blueyonder.co.uk
Note:- In order to reduce spam, any email without 'Brian Gaff'
in the display name may be lost.
Blind user, so no pictures please!
"SS" <none...@blueyonder.co.uk> wrote in message
news:6Na7q.152959$29.2...@newsfe08.ams2...

SS

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Aug 31, 2011, 4:53:37 AM8/31/11

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"Brian Gaff" <Bri...@blueyonder.co.uk> wrote in message
news:j3kpos$ink$1...@dont-email.me...

Brian it is one of those lamps that you just tap it and it changes the light
ouput (3 different levels) so I guess it must have something built in.
It doesnt have an on/off switch, just tap it and it goes off or on.

Dave Plowman (News)

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Aug 31, 2011, 5:10:48 AM8/31/11

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In article <x3e7q.166537$Z04.1...@newsfe07.ams2>,
SS <none...@blueyonder.co.uk> wrote:

Try moving them apart. This will show if it's RF or mains borne
interference.

--
*Pride is what we have. Vanity is what others have.

Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.

John Williamson

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Aug 31, 2011, 1:30:35 PM8/31/11

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Triac controlled by some circuitry which senses the hum induced by your
finger when it touches the lamp. The triac can generate RFI when there
is no suppression fitted or it is missing. If you radio has poor AM
rejection on FM, then that's what's causing your buzzing. Moving them
apart, even by a few inches, will help.

charles

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Aug 31, 2011, 2:32:00 PM8/31/11

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In article <9c79d9...@mid.individual.net>, John Williamson

I have one of those lights right beside my DAB bedside radio. No problem.

--
From KT24

Using a RISC OS computer running v5.16

Andy Champ

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Aug 31, 2011, 3:38:07 PM8/31/11

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On 31/08/2011 19:32, charles wrote:
> I have one of those lights right beside my DAB bedside radio. No problem.

Finally a good word for DAB!

Seriously I'm not surprised. It must surely be designed to reject a
little mains hum.

Andy

charles

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Aug 31, 2011, 3:43:18 PM8/31/11

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In article <VImdncUan-sCEMPT...@eclipse.net.uk>,

It won't be a little mains hum. It could be nastly spikes caused by the
dimmer, albeit a mains frequency.

> Andy