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Old 28-06-2009, 17:22
SWIZZ?
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Has anyone found & cured this problem?

I connected my headphones radio base to the red & white RCA connections on the HDR.
There is a hum which doesn't occur when similarly connected to a Pace Sky+ box.

I tried moving the radio base around with no effect.

David
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Old 30-06-2009, 17:53
germanycalling
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Has anyone found & cured this problem?

I connected my headphones radio base to the red & white RCA connections on the HDR.
There is a hum which doesn't occur when similarly connected to a Pace Sky+ box.

I tried moving the radio base around with no effect.

David
I use the red & white connectors to my trusty Denon amplifer (stereo) and the audio quailty is perfect. I use it a lot for radio. On a sample of one I would conclude that this has to be a local problem. Could this be[LIST][*]something radiated out of the Foxsat which is not present in the $ky box? Different frequency for the display for example?[*]Are you using a two pin power connection or three for the headphones base? Could it be a grounding loop?[*]If it is two pin power have you tried rotaing the plug 180 degrees? Sounds daft I know, but I have had some sucess in doing this many moons ago![*]Do you have audio out on the TV? If so what happens if you connect the headphone radio base to that?[/LIST]
Just thinking out loud here ..............
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Old 30-06-2009, 17:58
grahamlthompson
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Has anyone found & cured this problem?

I connected my headphones radio base to the red & white RCA connections on the HDR.
There is a hum which doesn't occur when similarly connected to a Pace Sky+ box.

I tried moving the radio base around with no effect.

David
You could try the audio out from the vcr scart using a scart to phono adaptor
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Old 30-06-2009, 21:38
SWIZZ?
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You could try the audio out from the vcr scart using a scart to phono adaptor
Thanks Graham.
So far I've found one adapter is completely duff !
I have also a posh gold plated one which I will test in daylight.
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Old 30-06-2009, 22:22
SWIZZ?
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I use the red & white connectors to my trusty Denon amplifer (stereo) and the audio quailty is perfect. I use it a lot for radio. On a sample of one I would conclude that this has to be a local problem. Could this be[LIST][*]something radiated out of the Foxsat which is not present in the $ky box? Different frequency for the display for example?[*]Are you using a two pin power connection or three for the headphones base? Could it be a grounding loop?[*]If it is two pin power have you tried rotaing the plug 180 degrees? Sounds daft I know, but I have had some sucess in doing this many moons ago![*]Do you have audio out on the TV? If so what happens if you connect the headphone radio base to that?[/LIST]
Just thinking out loud here ..............
Thanks Germanycalling.

If I call your bullet items A B C & D.
A-- My Sky+ is stacked on the HDR, so unless the Pace Sky+ is a perfect shield then this is not the answer.
B-- Yes it is 2 pin, & the boxes a are giving shocks a bit more than a tickle to my sweaty forearms when changing connections! Tomorrow I will look at earthing the 2 boxes, & see if this changes anything.
Both boxes are double insulated. So this is probably induced electricity. At least it is not leakage & over 30mA or my house supply trips.
C-- Tried that - no change. I do have an alternative AC to DC converter which I will try. (both ways round)
D-- This is possible but difficult to reach & would stop me eliminating sound on main speakers without stopping sound on headphones. ( I think ) will try & see if true!

Just tried simple headphones on a lead. Works well but I don't like trailing tripping leads.

It all seems v strange.
I am moving house in a few weeks so will make sure that backs of boxes & TV are accessible in the new one.
David
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Old 04-07-2009, 14:33
germanycalling
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B-- Yes it is 2 pin, & the boxes a are giving shocks a bit more than a tickle to my sweaty forearms when changing connections! Tomorrow I will look at earthing the 2 boxes, & see if this changes anything.
Both boxes are double insulated. So this is probably induced electricity. At least it is not leakage & over 30mA or my house supply trips.
I assume the 30mA is residual current and not earth leakage

It just occurred to me that I got more of a "poke" rather than a tickle from my FTA box once. That turned out to be a duff SCART lead which was giving me something nasty (~100V) from my CRT TV. A colleague at work suggested it might be the SCART lead and he was right!

Last edited by germanycalling : 04-07-2009 at 14:34. Reason: typo
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Old 04-07-2009, 20:46
SWIZZ?
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I assume the 30mA is residual current and not earth leakage

It just occurred to me that I got more of a "poke" rather than a tickle from my FTA box once. That turned out to be a duff SCART lead which was giving me something nasty (~100V) from my CRT TV. A colleague at work suggested it might be the SCART lead and he was right!
I have not used a CRT for 2 or 3 years.
However, on a recent caravan trip, sound was good but vision was only possible with a RCA connection! Either the scart lead itself or my 20" LCD caravan TV had a fault. I have many scart leads so I'm going to finish with a pile of goodies & badies. I'm just hoping that my 799 Euro 2 years old camping TV is not in the baddy pile
I never have liked scart leads !!
The hum problem was with my home 32" Panasonic LCD.
I have been too busy with house moving preparations, to check out all the possibilities kindly provided by you, Graham & a PM.
I'll get back later when I've checked out everything suggested, or pulled out my remnants of hair !!
Might be the headphone sender, we get lots of lightening here. Just this am had 2 power trips, one after a strike to a field about 200m away. At least its not boring here!!!

David
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Old 12-07-2009, 13:23
SWIZZ?
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I'm sorry to take so long to get back, we are moving house shortly & the headphones got lost in pre-packing.
Found them today & checked out your suggestions but they made no difference.
Thank-you germanycalling, graham & PM for trying to help.

I was just about to repack them in the waste container but noticed they had a change-over switch SRS--Stereo.
Stereo works with both Sky Pace & HDR (via RCA on STB & on Scart adapter.
SRS works only with Sky Pace but to my taste not quite as good as the stereo position.

I presume SRS is some sound system that is not supported by Humax HDR.

Thanks again to those who offered help !
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