[600MRG] My Antenna is Freezing

[patrick hamel]

Paul,
Of course the cold shrunk the coil and the wire.
You say the antenna is hanging from the tree like mine was.
When the sap in the tree freezes it no longer is conductive and reflecting back to the antenna the reactance and load which you tuned out when it conducted.
Since it is so cold, you probably did not use an R+/-jX meter in the vertical wire which might have shown you the coupling change 
(before the meter semiconductors froze)!
The bigger the diameter of the radiator, the less the losses, but nobody in his right mind (even a ham) would go build a 6-wire cage radiator a foot in diameter in this winter weather.
73,
Pat W5THT





----- Original Message -----
From: "Paul Signorelli" <w0rw1 at msn.com>
To: 600mrg at w7ekb.com
Sent: Thursday, December 7, 2017 8:02:31 AM
Subject: [600MRG] My Antenna is Freezing

What is de-Q'ing my antenna?

Temp went down to 4F last night and my 30 foot vertical (Hung in a tree) was up to

1.7:1 SWR.

I have been retuning the antenna to keep it 'on frequency' but the SWR is going up and the antenna is broader,

(lost Q).

Normally at 40F it is 1.1:1.

I have heated the antenna coil in the past with a 20A AC supply but that didn't change anything, (the antenna coil is outside).

I wacked the vertical antenna wire but there was no frost on it and that didn't change anything.

Is my ground freezing?

Of course it is...

Could I heat my vertical wire by adding a parallel wire?

Paul   w0rw

@ Ice Station Zebra,

Colorado
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