[K6BW] N2NL's musings and station progress

[David Mueller]

Hi guys,
   I wanted to let everyone know about some progress
at K6BW and my future plans....and some random
comments thrown in...

1) Importance of grounding:  I've been having problems
particularly on SSB with RFI getting into my FT1000MP
at the club station.  The problem is obvious - the TH7
tribander is sitting about 20ft above the operating
position.  Today I ran a low impedence ground from
every piece of equipment - both radios, both
amplifiers, both computers, and even my keyer, to the
ground wire in the trench.  Wala, SSB RFI problem
gone.  I haven't checked whether or not my computer
keying lines are now free of RFI (they would lock up
in a key-down state when transmitting), but I think
they will work.  Grounding is sort of a mysterious
thing.  You wouldn't think you'd need it with the
ground lug on the power cord, but in many instances it
really helps.  In many cases, the ground wire in the
power cord has a significant impedence to RF and an
additional ground is required.  This was one of those
cases.

2) Line noise:  15M, and to a lesser extent 10M, have
been essentually useless due to heavy line noise.  I
drove around the neigborhood with the AM car radio,
and  all the high tension lines were quiet.  Bill
suspected the cell building as the source, so I dug
out my trusy noise finder, a portable SW radio.  I've
had luck finding noise sources by changing the length
of the whip antenna and using my body to block the
signal.  I walked all around the hilltop, and the
noise was always loudest while pointing toward the
shack, not the cell building.  I tracked a significant
noise source to the makeshift UPS/battery charger in
the storage room.  59+20 noise went away when I turned
the charger off.  There may be another noise source,
but it's barely there and may not be local.  There IS
some digital stuff that comes and goes on HF, and
that's from the cell site.  It is intermittant, and
liveable since it only lasts a few seconds at a time. 
I suspect it's just fundamental overload due to
proximity, and I think the cell setup is clean.  Dirty
connections in a cellular application would create
huge losses in the UHF ranges and I can't believe they
would allow for that in their installation.

3) Future antenna plans:  I completed the 75M delta
loop for the AM transmitter and I'm waiting to put it
in the air.  I will not climb without the proper fall
protection, and the harness I ordered should arrive
any day.  Once that shows up, you'll see significant
progress in improving the antennas available at the
shack.  My eventual goals are a full size, 160M
sloping dipole with one end at the top of the tower,
an 80M delta loop for DX/CW, the 75M delta loop for
AM, the existing 75M dipole will be rebuilt (for
proper match) and placed in a sloging configuration
from the south of the tower, a couple more dipoles,
and a full sized 2 el delta loop yagi for 40M.  I plan
on getting the crank-up tower installed over my winter
break from classes (January).

4) CQP: This weekend if the California QSO Party, a
contest where the entire world is looking for CA
stations.  Marin county is a relatively rare county,
and I plan to activate K6BW primarily on CW for at
least a couple hours this weekend.  It's too early
know exactly when I'll be there, but feel free to drop
by.  It's a fun contest from the California side with
a chance to make lots of contacts.  The exchange is
QSO number and the County (send MARN for CW).

5) R5 vertical:  Amungst the aluminum stuff, Bill got
ahold of an R-5 vertical.  This is a counterpoise, no
ground, half wave vertical for 20/17/15/12/10M.  The
antenna won't blow away any pileups, but it's a good
antenna to use for demonstrations. It goes together
easily and can be installed with little effort.  I
recommend the club keep it seperated from the big pile
of aluminum for this purpose.

That is all....
73, Dave N2NL


		
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