Monitor interference.

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bigbassman
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Monitor interference.

Post by bigbassman »

Guys I'm at my wits end with this.No matter what antenna I use with my DX-394,I get severe interference from my computer monitors.I've compared results with the PC switched off and the difference is phenominal.I can do MW DX,aeronautical HF,the lot in relative peace,but the minute I switch the PC on,and those 2 bloody monitors kick into life,and all hell breaks loose.A loud rasping noise blasts over everything,depending whats showing on the screen.A lot of white isn't as noisy as something with a lot of colour,but Jeez,talk about spoiling your enjoyment big time.Is there any way around it,do you think? I've lined the inside of the DX-394 with adhesive metal foil,in the vain hope that it might help,but no.My desk is relatively small,so moving the monitors over a bit isn't really possible.I'll try anything.TIA.
2 X PRO 2006 1 X DX-394 1 X GRE PSR 282 1 X UBC780XLT with ProScan 1 X Pro43 1 X Yaesu FRG 100 Uniden 125 XLT LCL 2740.
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DX-Digger
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Re: Monitor interference.

Post by DX-Digger »

Fit ferrite chokes at each end of the monitor leads
and on the monitor mains cables at the monitor end of the cable.
Infact it could be coming from any lead from your computer.
So ferrites on all leads.
Also add a ferrite to the mains lead of your scanner at the scanner end of the lead.

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HTH cheers Mark
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bigbassman
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Re: Monitor interference.

Post by bigbassman »

Thanx Mark,I've taken all that on board and just ordered 10 off Ebay.I sure hope it helps.
2 X PRO 2006 1 X DX-394 1 X GRE PSR 282 1 X UBC780XLT with ProScan 1 X Pro43 1 X Yaesu FRG 100 Uniden 125 XLT LCL 2740.
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andymuza
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Re: Monitor interference.

Post by andymuza »

Does your monitor have a built in PSU or external one?
What connection from PC are you using, HDMI, VGA or Display Port?
What is your GPU?
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Cornelius
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Re: Monitor interference.

Post by Cornelius »

You probably have an earthing problem... Try to connect a wire from chassis of your computer to the chassis of your radio...

Just try... :)

(I know it's not the right way, but...)
bigbassman
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Re: Monitor interference.

Post by bigbassman »

andymuza wrote: 30 Aug 2018, 17:14 Does your monitor have a built in PSU or external one?
What connection from PC are you using, HDMI, VGA or Display Port?
What is your GPU?
Monitors have built in power supplies
VGA connections
GPUs are Nvidia GeForce 310.
2 X PRO 2006 1 X DX-394 1 X GRE PSR 282 1 X UBC780XLT with ProScan 1 X Pro43 1 X Yaesu FRG 100 Uniden 125 XLT LCL 2740.
mw0uzo
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Re: Monitor interference.

Post by mw0uzo »

If they're radiating that strongly, you will probably have difficulty in taming them. If a PSU is poorly filtered at the source of the interference (the main SMPSU switching transistor) then any length of lead between it and ferrites will radiate. The noise has to be shorted away to ground via capacitors and blocked by large inductors before going to the mains lead. In a few cases, the ferrites will work but anything that has significant design shortcomings or cost savings will just be an endless pain. I've also had poorly screened VGA/DVI leads that radiate. Good luck. You may have to consider different monitors, or check to see if filtering components are fitted in the power supplies, and if not, fit them. Very annoying.

Also, as mentioned before it could easily be the PC power supply. Cheap ones have no filtering and rasp like hell over everything. Check if the noise happens with the PC on but displays disconnected.
bigbassman
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Re: Monitor interference.

Post by bigbassman »

Thanx for that mw0uso.At the moment I cant do anything because due to a house move to a smaller house due to my wifes(and mine)poor health,all my radios and computers are at present languishing in cardboard boxes in a cupboard,until I can find somewhere to set them up.I'll bear it in mind tho'.
2 X PRO 2006 1 X DX-394 1 X GRE PSR 282 1 X UBC780XLT with ProScan 1 X Pro43 1 X Yaesu FRG 100 Uniden 125 XLT LCL 2740.
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