Topband: Beverage on Ground

[ZR]

----- Original Message ----- 
From: "Ashton Lee" <Ashton.R.Lee at hotmail.com>
To: <topband at contesting.com>
Sent: Thursday, November 29, 2012 1:20 PM
Subject: Topband: Beverage on Ground


No, I didn't spill my beer.

But I am having very good experience with the roughly 300 foot Beverage on 
Ground that I just put in at my house. It is fed through a 300 ohm 
transformer and runs in the only direction where I can get a 300 foot run. 
It is made of insulated #14 wire and unterminated, as I would prefer a more 
omnidirectional pattern since I can have only the one compromise receive 
antenna. Also I couldn't get a ground rod in to experiment with. In Western 
Colorado we aren't all that big on soil… but we sure have great rocks.


** I also live on a rocky hilltop as opposed to a CO mountain and currently 
have 3 500' BOG's in place mainly for 160 and to minimize neighbor noises. I 
also have 5 two wire reversible regular Beverages of 500-750' wandering thru 
the woods.


So far the BOG out receives both a K9AY I had up briefly (which, of 
necessity, was probably too close to my transmitting antenna) and a tuned 
loop I tried.

** That is no surprise.

Now I want to put up a similar antenna on the remote hilltop where I have a 
cabin and "contest site-lite". That location is ideal for transmitting 
antennas since it is on the absolute top of a mountain with cliffs down to 
the North and East of the property, and steep hillside to the South and 
West. But it makes running Beverages a bit of a trick. I also have 200 elk 
running around so it isn't easy to install wires above ground. This whole 
place is on rocks dusty soil where getting any sort of grounding requires a 
jack hammer. So I want to install one or two BOG's there as well. Which 
prompts several questions:

1) Should I again use insulated wire or can I use the cheap electric fence 
wire I can get at our ranch coop?

** Absolutely. There is enough low ground cover here that the BOG's are 
actually a few inches above the forest top soil which is only a few inches 
thick and the bony sand another foot or two to solid rock. That slight 
elevation seems to make a difference since they work decently to 40M; no 
preamps.

2) How do I get enough signal to noise without getting excessively 
directional. Is there anything like an optimal length for a less directional 
BOG?

** Each location will be different, experiment until you find a sweet spot.

3) My first experimental BOG works much better on 160 than 80. Is there 
anything unusual about that or that I should do differently?


** Likely the ground coupled losses have caused 80M to be electrically too 
long due to the reduced velocity factor.  Mine seem to be sharper than an 
elevated Beverage on 80 and while 40M is down it is very useable.


4) I have essentially no local noise in either my regular home or at the 
cabin. So I am mostly concerned with suppressing atmospheric noise. Any 
implications for that in my design.

** Ive all sorts of noises so just try to maximize F/R rejection and or 
local noise pickup off the front. Havent tried a 2 wire BOG yet.

I know that both my current and my contemplated antennas are sub-optimal. 
But a lot of what you have to do on 160 is less than optimal if you live 
anywhere but a large farm. The first test antenna is working so much better 
than receiving on my transmit antenna that I think sub-optimal antennas, of 
a reasonable quality, can work pretty well for me.


** The best thing to do is read a wide range of whats published on here and 
elsewhere. Dont get caught in the trap where a small few are always 
complaining about what others do and report. Someone on high conductivity 
pasture land doesnt have the experience to say what happens on a rock 
pile....comments are only guesswork. According to them I shouldnt be able to 
hear or work anything (-; but Ive never had the luxury of anything except 
the worst possible New Hampshire soil.


Incidentally for anyone experimenting with BOGs I am using an old MFJ active 
antenna tuner on the antenna I just built. It serves as a preselector and 
possibly a preamp it would seem. It gives me better performance than sending 
the antenna directly into the rig. One always suspects that if an MFJ 
product works OK there could be something else which would work a lot 
better. But early days so far. So far the BOG really cuts down on the noise 
while giving me enough signal.


** Just keep experimenting until YOU ARE satisfied. I even tried a Johnson 
KW Matchbox 30 years ago on a Beverage for 40/80M; didnt have a 160M TX 
antenna or amp capability then.


After all the help I got yesterday with one antenna question I was prompted 
to ask another.

KQ0C
Ash

** This site is a great resource.

Carl
KM1H
_______________________________________________
Topband reflector - topband at contesting.com


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