K9YC added:
> >Instead of grounding, look at decoupling -
>
>I know you guys are tired of hearing it, but the answer is pin 1
>problems in the ham gear and computers we use to the control the ham
>gear. Now, choking stuff, as Brett describes, can help that. But the
>best answer is to fix/work around the pin 1 problems, and, as Tom
>Rauch reminds us, put the RF into antenna in a manner that it
>doesn't bounce back down the line.
>
>http://audiosystemsgroup.com/publish
>
>See the stuff on pin 1 problems, and also the stuff on ferrites and
>RFI.
Good point - though for all the radios to have a pin 1 problem is a
little odd (though if it is another device that's locking up, maybe it
has a pin 1 problem itself).
With attention paid to make sure I don't have any grounding
problems (or earthing, as being several floors up I don't bother
with any of it - just keeping the RF out of stuff), I have found the key
to keeping things behaving themselves properly when the shack is in
the antenna's near field is often possible with just that little bit more
decoupling. In such an extreme situation, a pin 1 problem could very
well make it a non-starter to begin with.
Luckily, I have yet to encounter one, but beware - quite a bit of
equipment has nothing to keep the nasties out (OMNI 6 & WX0B
SO2R boxes here required bypass caps as they had none - now
look at the JA stuff, with some external connections having even
series inductance & then consider how the average JA station is
probably more like K9OM's or mine than that of the typical station in
NA).
For those looking in the archives later, Jim's papers are definitely
worth downloading - even if you have a b'cast background. The black
magic of RF applies to all disciplines & never gives up. If you are
close to the antenna, there numerous potential culprits - even ones
you might not expect.
73, VR2BrettGraham
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