Here is something I saved from a previous discussion about grounding. I
haven't tried it, but several hams have testified that it has worked for
them.
Hi list:
i think it was John who was saying that he has some grounding problems
being on the second floor.
I found a good method of helping to get rid of some of the floating
ground problems.
You use a peace of RG58 coax and put a 4.7 peaka farad seramic
capacitor across between the ground shield and center line of the coax =
on each end of the length you will need to go from your station to your
ground rod or an adequet ground somewhere. Connect the center line of
the coax to ground and the center of the other end to the radio or to
your common station ground in the shack. This is supposed to help to
eliminate floating ground and keep all the extra RF going to ground
instead of coming back up your ground line.
Regards
Colin
----- Original Message -----
From: "tom behler" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, February 07, 2011 7:57 PM
Subject: Re: interesting RF problem in the shack
Steve:
I used this exact same set-up out in Colorado before I came back to
Michigan, and before I installed the Windom. In fact, it's what I ran the
Cross-country Blind ops net with last year, without a grounding system at
all.
The only thing I can think of that is different here in Michigan would be
the Windom installation itself. But, the Windom is on a completely
different antenna port on my Window feed through panel, and on my TenTech
manual tuner.
I will try grounding the rig-runner by connecting it to the common ground in
the shack, and will also try your ferrite solution.
Admittedly, before the Windom became unusable, I don't think I ever used the
DXCC back here in Michigan on 20 meters ever since we returned. Therefore
it's inpossible for me to tell if the problem existed before without my
knowing it.
73 from Tom Behler: KB8TYJ
----- Original Message -----
From: "Steve Forst" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Monday, February 07, 2011 9:33 PM
Subject: Re: interesting RF problem in the shack
Tom,
Grounding might not be a bad idea. Also, if you have any ferrites
around, I would try clamping a ferrite on the line from the power supply
to the rig runner, and also the line from the rig runner to the radio.
Maybe disconnect any other gear that is connected to the rig runner
to try and isolate the source. Perhaps move the rig runner as far as
possible away from the amp.
Have you worked that combo of antenna/amp/band before? Did this just
pop up out of the clear blue? If it worked fine before and now has
problems, what has changed in the station that you can try reversing?
And I thought I had problems...
73, Steve KW3A
On 2/7/2011 8:58 PM, tom behler wrote:
> Hi, all.
>
> Well, I know I'm going to get varying opinions on this one, but that's ok,
> since I'm looking for a number of possible alternative causes and
> solutions.
>
> As many of you know, I have gone back to using my Alpha Delta DXCC antenna
> as my HF antenna, until my Windom, which took a dump on Saturday, can be
> resurrected.
>
> The DXCC works great on 40 meters with both 100 wattts, and my Ameritron
> AL811H amplifier. However, when I went to do the Cross-Country blind ops
> net on 14.258 yesterday, I had an interesting experience. Things worked
> great with 100 watts, but when I kicked the amplifier in, and tried
> running
> things on the usual 600 watts, I ran into problems. As soon as I keyed
> the
> mic, the protective circuit in my Rigrunner tripped, and everything in my
> station went silent.
>
> I have no other indications of RFI anywhere else in the house or the
> shack.
> In addition, my SWR's are good with the DXCC on 20 meters (about 1.5 to 1)
> without the tuner, and obviously just as good with the manual tuner. I
> use
> my usual procedure to tune the amp, and everything works there as well,
> giving me forward and reflected power readings I would expect.
>
> Could anyone tell me what you think is going on here? Do I still have a
> grounding issue of sorts, even though I've gotten no indication of
> grounding
> issues with other applications?
>
> Other than reducing power, is there anything anyone can suggest for me to
> do
> to try to solve this problem.
>
> I was thinking of grounding the Rigrunner by connecting a ground cable
> from
> the cover of the Rigrunner to my common station ground, but just haven't
> gotten to it yet.
>
> It's just a strange problem, and only seems to occur on 20 meters with the
> amp. I never had the problem at all out in Colorado, where I had no
> station
> grounding system at all.
>
> 73 from Tom Behler: KB8TYJ
>
73,
Gale
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