T1 ATU used in attic environment

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T1 ATU used in attic environment

Kenneth Moorman
Hi All,

I am considering using my T1 to tune a couple of attic antennas, a 40 mtr dipole with drooping ends, and a horizontal loop of about 130 feet total length, as close to the feed point of each antenna as possible to reduce losses in the coax from shack to attic.  I would plan to use a relay to select between the antennas, the placement of same which would keep the coax length to about 6 feet after the relay to one antenna, and zero feet to the other.  Directly prior to the relay (toward the transceiver) I would place the T1.  I would use a small reed relay mounted in a pill box or something similar, to plug into the external tune jack on the side of the T1 to initiate the TUNE cycle, and observe the SWR on a separate SWR meter in the basement shack to know when the tune-up is finished.  My concern is the heat buildup in the attic during our hot, sticky Virginia summers.  Has anyone else tried to do this, and how did the T1 take the heat?  It's a great little tuner, but I doubt it was designed to take 120+ degree heat for extended periods.  Any thoughts and observations will be appreciated.   BTW, 10 watts from my K2 will be the max expected power for this setup to handle.

72,

Ken, NU4I
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Re: T1 ATU used in attic environment

Joe-aa4nn
Being an engineer I am sure you enjoy putting these kinds of pieces
together.
OTOH, the Ameritron 4-position switch placed in your attic will switch up
to four antennas.  The control voltage to activate the switch rides on the
coax.
One coax, four antennas.  Quality RG213 and your db loss ain't that much.
de Joe, aa4nn
-------------------------------------

Hi All,

I am considering using my T1 to tune a couple of attic antennas, a 40 mtr
dipole with drooping ends, and a horizontal loop of about 130 feet total
length, as close to the feed point of each antenna as possible to reduce
losses in the coax from shack to attic.  I would plan to use a relay to
select between the antennas, the placement of same which would keep the coax
length to about 6 feet after the relay to one antenna, and zero feet to the
other.  Directly prior to the relay (toward the transceiver) I would place
the T1.  I would use a small reed relay mounted in a pill box or something
similar, to plug into the external tune jack on the side of the T1 to
initiate the TUNE cycle, and observe the SWR on a separate SWR meter in the
basement shack to know when the tune-up is finished.  My concern is the heat
buildup in the attic during our hot, sticky Virginia summers.  Has anyone
else tried to do this, and how did the T1 take the heat?  It's a great
little tuner, but I doubt it was designed to take 120+ degree heat for
extended periods.  Any thoughts and observations will be appreciated.   BTW,
10 watts from my K2 will be the max expected power for this setup to handle.

72,

Ken, NU4I

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Elecraft mailing list
Post to: [hidden email]
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
 http://mailman.qth.net/mailman/listinfo/elecraft   

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com