Actually with freshwater below and ice at the top, they would not be like a
BOG. They would not be like a suspended antenna either, but somewhere
between and probably much closer to a Beverage in air than a BOG.
Insulating the wire would not help much (if any), because the ice is already
an insulator and the ice beyond the insulation dominates the loss and
reduction of wave velocity in the wire.
The general order is air, ice, rock, fresh water, dirt, and saltwater...but
it all depends on temperature (for ice) and what is in it.
73 Tom
----- Original Message -----
From: "Guy Olinger K2AV" <k2av.guy@gmail.com>
To: "Eddy Swynar" <deswynar@xplornet.ca>
Cc: "Topband" <topband@contesting.com>; "Roger Parsons" <ve3zi@yahoo.com>
Sent: Friday, January 16, 2015 7:38 PM
Subject: Re: Topband: Beverage on Ice
I think I would take insulated Flexweave to make an "Ice-BOG". I would use
one of these Lithium-Ion hand held circular saws, with the depth of the
saw
set to a quarter inch, or whatever depth you think will protect it from
the
snowmobiles. Trench the ice with that and then push the wire down into the
notch. Pour water into the notch and let it freeze back. At the ends,
solder some bare #12 to the flexweave, enough to go to the bottom or 50
feet, and let it drop straight down through a hole in the ice. Those are
your "grounds". Don't bother with a termination resistor at the far end.
The wire to water will have a complex impedance that should be good enough
for a BOG. The rest is the usual transformers and feedline. Make the
flexweave 220 feet (67 meters).
Be the first to go ice-bogging. Keep notes and let us know wha hoppen. Be
a great NCJ article. :>)
73, Guy K2AV
On Fri, Jan 16, 2015 at 5:10 PM, Eddy Swynar <deswynar@xplornet.ca> wrote:
Hi Roger,
So very sorry to learn of your mobility issues there with that broken
leg...!
Personal mobility---or, rather, the LACK thereof!---is something that I
have come to know only all too well here, what with my dual knee
replacements of 2013.
Just a personal thought, or two, from me here: I would think that that
"...laid-atop-the-ice" antenna that you'e proposing would behave like a
BOG
antenna---and for that reason, I think I would rather have it insulated
with plastic along its entire length, rather than relying solely upon an
enamel coating to serve as its insulation.
Anyway, FWIW!
Stay warm, and RECOVER ASAP, Roger...
~73!~ de Eddy VE3CUI - VE3XZ
On 2015-01-16, at 4:51 PM, Roger Parsons via Topband wrote:
> I know that Beverages on Ground have been discussed on a number of
occasions, but:
>
> I live on the shores of a reasonably large lake, and at this time of
year it will be frozen to at least 2' and possibly 4' or 5' deep. I
believe
that ice is a pretty good insulator, so I wonder about the effectiveness
of
a wire just laid on the surface? It would be impossible to retrieve the
wire in the spring so it would have to be fine enameled copper. Even that
may not be very environmentally friendly? If the wire survived the first
couple of days it would be frozen into the ice - it would be at risk from
snow machines until that happened.
>
> This is just speculation from enforced idleness - I cleverly managed to
break my leg during a foolish last check of my receive antennas before
Christmas - so I can't even get into the shack, let alone onto the lake.
I
was not very hopeful in any event that EP6T would be workable from here,
but I am determined somehow to get there for K1N...
>
> 73 Roger
> VE3ZI
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