[Elecraft] Monitor noise

Fri Jun 14 09:07:01 2002

Have you also tried changing the Horiz and/or Vert refresh rate of the
monitor? Have you tried putting some distance between the monitor and your
rig?

In any case I suspect short of buying a Tempest certified system (e.g.
totally shielded) pretty much all consumer level monitors (and PC's) are
going to generate RFI... and certainly some worse than others. There are,
after all oodles of 'oscillators' in those things. Also good, quality full
metal case for the PC is a must (and plug up those open slot covers!)

Back in the mid/late 80's Compaq USED to design/manufacture really top
quality 'mil spec' stuff. No more tho, not in this day of the
Dell/Gateway/etc. cutthroat consumer market. Besides for those 'everything
for $900' deals I'd bet the Dells/Gateways/Compaq's OEM their montors
anyway, probably paying no more than $50 a pop from some offshore company.

Best to stick to manufacturers whos ONLY business is quality monitors, e.g.
iiyama, EIZO-Nanao. Or otherwise a large manufacturer that at least has a
division dedicated exclusively to monitors (Panasonic/Viewsonic, IBM, NEC,
etc.). Besides, long term you are not doing your eyes a favor by having a
cheap monitor. Trust me on this one, after staring at monitors for over 25
years, my eyes can no longer focus on anything under 3 ft away (I now have a
pair of special prescription glasses exclusively for computer work). Same
thing with keyboards (carpel tunnel anyone?). To avoid any future health
related problems there are three 'human/computer interface' things you
should never compromise on: the monitor, keyboard & chair.

I have both an NEC and a Panasonic. Both exhibit some RFI but nothing really
significant. However, it IS there though so I will shut them down if I'm
doing any weak SWL or wanting to really dig down deep for DX. I also have my
shack layout such that my PC/Monitor is on the opposite side from my rigs in
my 10X12 'shack' room (maybe 8-10 ft away). I use double shielded 'coax'
(98% braid + foil) for audio links to/from the soundcard.

Hope that helped.

73,
Mike - AD5IU
----- Original Message -----
From: <[email protected]>
To: <[email protected]>
Sent: Thursday, June 13, 2002 7:34 PM
Subject: [Elecraft] Monitor noise

> I'm nearing the end of my rope.......
> I've been trying to "noodle through" the problem of horrible noise to my
> K2(and other HF rigs) from my Compaq Presario MV500 computer monitor. I
> picked up a boatload of snap-on and varried ferrite beads of all shapes
> and sizes and installed them on every cable coming in and out of the
> computer and monitor and power cables to the radio and computer. There
> was no change in the noise which is 7khz wide and appears every 50khz or
> so on almost every band. (Also, my radio and computer equipment is
> grounded to a ground strap connected to a cold water pipe 4' from my
> operating desk. )
>
> It seems that the problem might lie in the design of the monitor, but
> I'm trying to avoid buying another one. Has anyone had any success
> solving this problem? Or, can anyone recommend a different compatible
> monitor that solved their problems?  Any thoughts on the flat-screen
> monitors?  I'm quite sure that I'm missing oodles of DX hidden behind
> these various "walls of noise" :-)
>
> Thanks!
>
> Paul    kb9yvp
>
>
>
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