Anyone have experience with horizontal loops in a triangle shape?

I have trees on my property that will allow this configuration. I'll
have about 100' on each of the three sides. It is pretty much an
equilaterl triangle, and the height should be about 60 feet. I'd like
opinions before I go to the effort of getting it up. I'd also like
opinions on whether or not it should tune at all on 160M. I have an MFJ
balanced tuner to feed the 600 ohm ladder line I plan on using.

Ed K7AAT

Triangle will work fine.

160m probably not; it's a bit short. It would help if you included a
relay opposite the feedpoint to open it on 160m.

73,
Dan

Ed G wrote:
Anyone have experience with horizontal loops in a triangle shape?

I have trees on my property that will allow this configuration. I'll
have about 100' on each of the three sides. It is pretty much an
equilaterl triangle, and the height should be about 60 feet. I'd like
opinions before I go to the effort of getting it up. I'd also like
opinions on whether or not it should tune at all on 160M. I have an MFJ
balanced tuner to feed the 600 ohm ladder line I plan on using.

Ed K7AAT

Triangle will work fine.

160m probably not; it's a bit short. It would help if you included a
relay opposite the feedpoint to open it on 160m.

I've read of people using an L/C resonant trap instead of a relay, for
just this purpose. The trap opens the loop on the lowest band, and
appears as a capacitive reactance in series with the loop on the
higher-frequency bands.


--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

(Dave Platt) wrote in news:12aroqj2chrpu45
@corp.supernews.com:


Triangle will work fine.

160m probably not; it's a bit short. It would help if you included a
relay opposite the feedpoint to open it on 160m.

I've read of people using an L/C resonant trap instead of a relay, for
just this purpose. The trap opens the loop on the lowest band, and
appears as a capacitive reactance in series with the loop on the
higher-frequency bands.




That's interesting, Dave. Thanks. Will look into that as a relay would
be tricky given the location and height of my proposed loop.

Ed

Trap seems like a fine idea...

If it were not a multiband loop, I think you could use a relay with the
coil in parallel with the contacts, so you could run DC on the feedline
(if it were a dual bander of some sort) but the high voltages present
on the open wire feeder would make it awfully hard to choke off the RF
for whatever DC injection scheme you were using. I think you'd
basically need a tuner with DC continuity, and the CLC tee that is so
common in tuners isn't one.

I guess you need a big enough C on the higher bands to look like a
short circuit in that trap if you want to have the loop appear to be a
closed loop, but maybe that's not very important.

73,
Dan

A relay inserted in an antenna wire can be operated via a pair of
wires (20 gauge twin speaker cable) which, in parallel, form the
single antenna wire.

At the shack end, DC power is fed into the pair of wires via an RF
choke. The choke consists of a pair of wires (more 20 gauge twin
speaker cable) wound on a ferrite rod.

Been there. Done that! I used a single-contact reed relay.
----
Reg.

Ed G wrote:
Anyone have experience with horizontal loops in a triangle shape?

I have trees on my property that will allow this configuration. I'll
have about 100' on each of the three sides. It is pretty much an
equilaterl triangle, and the height should be about 60 feet. I'd like
opinions before I go to the effort of getting it up. I'd also like
opinions on whether or not it should tune at all on 160M. I have an MFJ
balanced tuner to feed the 600 ohm ladder line I plan on using.

Ed K7AAT


Hi Ed,

Your Loop is about the same as I'm using here it works great on 80-10m
But 160 is a bit of a stretch for it.. and I use an inv. L on that band
when I'm active there. But it's been a great loop here on the other
bands. You might try it first before adding relays and traps .. how
well it tunes will depend upon the range the tuner will handle. It
should give a good high angle lob on 160 and be good for local out to
say 500 or 1000 miles.
73 Dave KC1DI

Reg Edwards wrote:
A relay inserted in an antenna wire ...
Been there. Done that! I used a single-contact reed relay.

No arcing problems?
--
73, Cecil http://www.qsl.net/w5dxp

Reg Edwards wrote:
A relay inserted in an antenna wire ...
Been there. Done that! I used a single-contact reed relay.

No arcing problems?
--
73, Cecil
==================================
No arcing problem that I ever detected. Transmitter was 100 watts. I
think the relay was rated at 750 volts and it may have been a vacuum
type. Only used on the 160 and 80m bands.

It eventually failed because of intermittent contact on receive when
no wetting current flowed. Perhaps it should have been mercury
wetted.
----
Reg.

Reg Edwards wrote:
No arcing problem that I ever detected. Transmitter was 100 watts. I
think the relay was rated at 750 volts and it may have been a vacuum
type.

That's a pretty husky reed relay but you are lucky
it didn't arc. Peak-to-peak across that relay was
higher than 750 volts if it was installed in a 1/2WL
dipole.
--
73, Cecil http://www.qsl.net/w5dxp