Hi Terry:
Well, the noise level has been lowered a lot, but I'm still getting
higher noise levels than I think I should. On 40-meters, I am getting an
average of S2-4 peaking at S5 around the time thunderstorms begin to form.
Can I have your weather, please? Out here in the midwest (MO), it's not at
all unusual for me to have S9+ noise during the summer months when
thunderstoams are still quite some disstance away.
I'd KILL for ONLY S2-S4 atmospheric noise on 40M!!!
I've put up a vertical which helped. Putting down 12 tuned radials, 2 for
each band, helped even more.
Unfortunately, as soon as you 'put them down' on the ground, they're no
longer 'tuned', but they will still work WELL! SO don't sweat it one bit.
Moving the power supply a few feet away may have also made a difference
but I can't tell by ear.
Probably only if it had a sizeable electro-magnetic field which might have
been 'modulating' the K2's PLL... which is generally doubtful, bot not
totally out of the question.
I am using the standard red/black zip type supply line from the power
supply to the radio. I am wondering if going to coax to supply power to
the radio may not drop the noise level even more? I would think that the
R/C tank in the radios power circuit would take any ripple or noise out
but maybe I'm wrong.
Going to coax INSIDE THE HOUSE, will probably not be worth the added
effort. 90%-95% chance whatever noise you're hearing is NOT being generated
IN the house... and whatever might be, probably won't be filtered out by
using COAX.
I also have a ground that is a 20' long piece of 10GA bare copper wire
running to a single lightning rod from a second story window. I'm now
wondering if this wire isn't acting like part of the antenna or maybe
injecting my transmitted signal back into the receiver via the power
supply. Since I'm only running 5-10 watts output, should I use coax for
the ground as well and decouple it with ferrite beads just in case?
Actually, the ground you have is probably NOT being very helpful with
regard to acting as an RF ground. But it might be helping a bit as an AC
ground. It's probably long enough that it has more than ample reactance at
HF to make it appear as a high impedance (e.g. not an RF ground). If you
feel you need it for RF purposes (counterpoise or RF ground), you might
want to consider 'tuning' it with something like the MFJ-931 'Artificial
Ground':
http://www.mfjenterprises.com/products.php?prodid=MFJ-931
This is one of the few MFJ products which I feel works as advertised, and
decently well, too. But, it is a 'specialty' device, and I'd recommend it
ONLY if you need it for providing an RF ground from the 2nd floor. It will
probably NOT help get rid of any noise you might be receiving.
Such a device can be built for wuite a bit less than the $90 they're asking
for it... takes a small tuning capacitor, an inductor, a meter, and a SMALL
handful of additional parts... might not look as pretty but it'd be
functional. Making it 'purty' comes AFTER you make it work.
For a beginner, this is all pretty confusing! I read so much, trying to
come up to speed quickly. The problem is that I begin confusing which
solution goes to what problem I remember reading about last month in some
periodical can't remember.
You're a General Class amateur, try using 20 meters during the day and
early evening, rather than 40M. 20M (actually any band higher in frequency
than 40M) will be lower in atmospheric noise, and my produce better
listening conditions.
During the summer, 40M and 80M generally are pretty noisy, due to more or
less local storms... being in CO doesn't help your case much, as I've seen
how readily those storms can kick up out there (here too!). There's
NOTHING(!!!!) you can do about this, other than go to a higher frequency
band and hope it's open to somewhere. As you get closer to Fall, the
atmospheric conditions will moderate and 40/80M will again become much more
productive... and quiet... but right now, you can't fight Mother Nature...
so go with the flow, take your lumps and find a quieter band, if you can.
73,
Tom Hammond N0SS
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