Topband: Need to know more about beverages...

Gary Smith Gary at ka1j.com
Sun Jan 31 09:04:29 PST 2010


Well, it was a scramble trying to make these hastily thrown together 
beverages for the contest. I found some interesting discoveries which 
means I need to learn more.

Radio is a K3. The preamp is turned off in the K3

Beverage 1 runs from the house to the east and is 500' long. The wire 
comes in through the window sill and is held up by branches & it 
dips,. It has no termination resistor. The matching transformer is 
next to the window. The ground is connected to the station ground 
rod.

Beverage 2 runs due north and is 350 feet long. it is connected to 
100' of TV cable and it is grounded at the feed point 100' from the 
house where the matching transformer is. There is a 350 ohm carbon 
resistor (parallelled resistors) at the north tip and a 6' ground rod 
in swamp muck

Both Beverages are about 8 feet off the ground except #1 which is 
settling down in the marsh reeds to where it will be closer to the 
ground at the distal end.

K9AY is beside the house

INV-L is 350 feet from the house, about 70 radials 130' each.

Problem for me for an example is I can not hear JAs where others in 
the area are working them.

My K9AY is much better in killing atmospheric noise than the vertical 
but it still does not pick up those JAs.

So I decided to try these beverages to see how they do.

My discoveries are thus: Both Beverages are full of atmospheric 
noise. Both of the beverages definitely had a good gain over the K9AY 
but the K9AY heard most everything these beverages heard but the 
noise was tremendously lower than the Beverages. The RF signals were 
attenuated a bit but the S/N ratio was by far better with the K9AY.

I have the K3 configured so the main receiver listens through the Inv-
L and the sub receiver uses the Rx antennae. I have all 3 Rx ants on 
a coax switch and this goes into the control head of the K9AY so I 
can use that pre is I wish. 

The atmospheric noise was so bad with the beverages I sometimes found 
it better to use just the main Rx & the Inv-L only to cut down on the 
atmospheric.

It's my understanding the Beverage is supposed to be a quiet antenna 
but as mine are not, perhaps there's an obvious reason why mine 
behave so badly? #1 is in a salt marsh with nothing around it and #2 
runs along the marsh and terminates just before railroad tracks.

I surely must be doing something wrong.

Thanks
Gary
KA1J


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