From: Rik Strobbe <rik.strobbe@kuleuven.be>
To: "rsgb_lf_group@blacksheep.org" <rsgb_lf_group@blacksheep.org>
Thread-Topic: LF: 137 kHz QRX
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Date: Thu, 15 Mar 2018 15:47:55 +0000
Message-ID: <1521128876279.30718@kuleuven.be>
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Subject: Re: LF: 137 kHz QRX
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Hi Paul,

to my knowledge snow and ice act as a very lossy capacitor for AC signals above some kHz.
Losses decrease with temperature, so the worst thing is snow and ice at temperatures just below 0°C.

73, Rik  ON7YD - OR7T

________________________________________
Van: owner-rsgb_lf_group@blacksheep.org <owner-rsgb_lf_group@blacksheep.org> namens N1BUG <paul@n1bug.com>
Verzonden: donderdag 15 maart 2018 16:23
Aan: rsgb_lf_group@blacksheep.org
Onderwerp: Re: LF: 137 kHz QRX

Hello Chris,

I went on a treasure hunt and found my variometers! :-) However,
digging them out of the snow made little difference. The antenna R
remained high, well beyond the range of my tapped matching
transformer. It's slowly coming down today and I think I may be able
to transmit tonight.

I don't recall reading about this anywhere, but it appears to me
this phenomenon may be related to snow or ice on trees. Whenever the
trees get coated with ice or wet snow, the antenna R goes up. It
stays up until the snow or ice comes off the trees. Sometimes that
means hours, other times days (ice followed by cold so it doesn't
come off). Whatever the cause, the lesson here is that I need a
transformer with wider range, and relays to change taps remotely!

We got two feet of snow this last storm. Total snow pack is now
about four feet. :-\ Good thing we had a warm spell before this
storm. Otherwise it would be six feet!

I hope you can get your coil redone soon. I've redone mine twice so far.

73,
Paul N1BUG


On 03/14/2018 07:14 PM, Chris Wilson wrote:
>
>
> Hello Paul,
>
> Get a big shovel out, weak excuse ;)
>
> Seriously  though,  the UK stops with a bit of a flurry of snow, hope you
> can  get back with a big signal soon, I'm still trying to find time to
> re-do  my  loading  coil  / variometer. And I don't even have freezing
> temps and snow as an excuse.
>
> Wednesday, March 14, 2018, 10:55:00 PM, you wrote:
>
>> I am not transmitting tonight. Weather problems. I am under so much
>> snow now that I may need someone to send a search party in the
>> spring. :-(
>
>> 73,
>> Paul N1BUG