I have a few questions about the VE3DO loop as described
at:http://www.k3lr.com/engineering/VE3DO/OptimizedDOLoop.pdf
With reference to Figure 1, are the 9:1 transformer and termination resistor
located close to each other, i.e. pretty much within a foot or two of each
other and the center of the antenna, or is there more separation? I was
guessing that for a 40 ft. top horizontal length, each of the bottom
horizontals would be somewhere between 18 and 20 ft. even though not explicitly
stated.
Can the ground of the transformer just be tied over to the ground of the
termination resistor without any connections to ground rods, mesh, radials etc.
and, if so, can the whole assembly be elevated to at least 8 ft. base height in
situations where people, animals, vehicles, yard/farm maintenance machines etc.
may need to pass under? I know that Flag antennas can be deployed this way
without the ground connection but could the VE3DO be also?
Has anyone looked into Vactrol remote adjustment of termination?
Another scheme would be 4:1 transformers at both sides, two 100 ohm balanced
lines (twisted pairs) to the operating position, a 4 pole 2 throw switch to
send one side to a 2:1 balun to receiver/amp coax. for the forward side and the
other side to a 0-250 ohm pot for in-shack termination control (would be
transformed to 0 to 1K at the antenna). That set-up would provide pattern
reversal via the switch.
The above set-up has been successfully done with Flags of reasonable size with
short (under 200 ft.) feedline distances.
Mark Connelly, WA1ION | South Yarmouth, MA, USA | FN41vq
<<Hello Wes;
The VE3DO loop has a much better front to back ratio compared to a K9AY.
The K9AY is easier to erect
73Tim K3LR
From: Wes Stewart [mailto:n7ws@yahoo.com]Sent: Wednesday, October 2, 2024 6:28
PMTo: topband@contesting.com; Tim DuffySubject: Re: Topband: Low frequency RX
antenna
Tim,
Why is this preferred over a K9AY?
Wes N7WS
On Sunday, September 29, 2024 at 08:10:12 PM MST, Tim Duffy <k3lr@k3lr.com>
wrote:
Greg, W8WWV has done some new work on the VE3DO loop.
I use 3 of them here at K3LR.
Greg's latest paper is here:
http://www.k3lr.com/engineering/VE3DO/OptimizedDOLoop.pdf
73Tim K3LR>>
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