Peter, Early in the days of switched-mode power supplies we found on LF that
those units left on standby often emit more interference than when they are
actually switched on. I have fallen foul of a PC power supply problem only
because it drifted into 136 when its fan failed and it got hot. Checks by
switching it on did not indicate a problem, only switching it off after it
had come into the band, triggered the understanding. Glad you sorted it.
Most of these kind of problems can exist in your own premises because the
field drops quite quickly as you mose away from the source and its radiating
mains cable (aerial)....though you are probably in range of next-doors
rubbishy equipment too :-((
Well done, I hope that puts some of the pleasure back in to LF/MF for you.
Cheers de Alan G3NYK
----- Original Message -----
From: "M0FMT" <[email protected]>
To: <[email protected]>
Sent: Thursday, November 06, 2008 3:37 PM
Subject: Re: LF: 500 noise - Rik: Yep its in the house!
Hi Rik and LF
Thanks for pushing me into doing some thing about my 500kc/s noise. You
would think a bloke my age would have got to grips with this earlier. You
were dead right The noise was coming from a DVD player that was on the face
of it switched off. Using a small MW radio proved otherwise. I have to pull
the plug out of the wall to shut it up. Surgery with a hammer is planned
next!!!
Oh yes I am now hearing things again hope to hear you and have that QSO.
73 petefmt
--- On Mon, 3/11/08, Rik Strobbe <[email protected]> wrote:
From: Rik Strobbe <[email protected]>
Subject: Re: LF: 500
To: [email protected]
Date: Monday, 3 November, 2008, 2:50 PM
Hello Pete,
I found out that 90% of the noise on 500kHz came from inside my own house.
A lot of electronics is running of switched PSU's and you need just one of
these oscillating near 500 kHz to get a lot of noise.
I took a small portable AM radio (tuned to the lowest end of the medium wave
band = abt. 520kHz) to locate the noise sources. Use the ferrite antenna to
take
null bearings.
After replacing a couple of 12V switched PSU's by good old linear ones
noise was down by 10's of dB.
Another source of noise are energy saving lamps. You can locate them the
same
way.
73, Rik ON7YD - OR7T
Quoting M0FMT <[email protected]>:
> Hi Mal and LF
>
> I would like to be on for two way QSO's however its the old story
here I have a high noise level and am not hearing any thing other than
local
signals.
>
> I was on the Suffolk coast for this years holiday. I only had a Kenwood
TS50 and a 40 metre dipole up. I was hearing just about every thing on
500kc/s. Its not as though I live in a high density area apart from a
neighbour
either side the nearest other is about 1/4mile away but I do have 11kV at
the
bottom of the garden which to date has not been a problem. So I suspect an
insulator but the noise is not general it is not affecting HF at the
moment.
>
> I have an 8 foot Octagon tuneable and rotatable loop that I am playing
with at the moment but so far no real improvement.
>
> Sorry for the tale of woe but we are working on the problem.
>
> Chris XIZ has suggested X band so I may try that shortly.
>
> 73 petefmt
>
>
> --- On Mon, 3/11/08, mal hamilton <[email protected]> wrote:
>
> From: mal hamilton <[email protected]>
> Subject: Re: LF: 500
> To: [email protected]
> Date: Monday, 3 November, 2008, 11:32 AM
>
>
>
>
>
> Peter
> Listening on 500 recently it looks like the GAS has gone out.
> Mal/g3kev
>
>
> ----- Original Message -----
> From: M0FMT
> To: [email protected]
> Sent: Monday, November 03, 2008 11:10 AM
> Subject: Re: LF: 500
>
>
>
>
>
>
>
>
> Nice one Warren .... :))
>
> Sorry Mal.
>
> 73 Petefmt
>
> --- On Sat, 1/11/08, Warren Ziegler <[email protected]> wrote:
>
> From: Warren Ziegler <[email protected]>
> Subject: Re: LF: 500
> To: [email protected]
> Date: Saturday, 1 November, 2008, 7:24 PM
>
> Mal,
> You have a gas powered TX?
> 73 K2ORS
>
>
> On Sat, Nov 1, 2008 at 2:55 PM, mal hamilton <[email protected]>
> wrote:
>> Hi
>> Is there anyone listening on 500 ? or am I just burning up gas !! now
CQ
> for
>> a qso on 502.6
>> de g3kev
>>
>>
>
>
>
> --
> 73 Warren K2ORS
> WD2XGJ
> WD2XSH/23
> WE2XEB/2
> WE2XGR/1
>
>
>
>
>
>
>
> No virus found in this incoming message.
> Checked by AVG - http://www.avg.com
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7:08 PM
>
>
>
>
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