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[W1JPP]

I have two antennas. One is a 160m doublet fed with open wire up at approx 50 feet. The second is an 80m end fed, feedpoint up about 15’, with 49:1 transformer then rises to 50’ then runs horizontal.

Both have very low noise (s2 usually, sometimes less) on most bands. On 160 it’s closer to s7.

I put up a beverage antenna. It’s fed with 9:1 unun/transformer I made. I have that grounded to a ground round and wide strap - tel he beverage is mounted about 7’. I only had room for 250 feet of wire and I did not terminate the end with a resistor and ground. So the termination is just an insulator tied off to a tree. I could only have the end pouting northeast so I did not want it directional and I’ve read if you leave it just tied off vs grounded with a resistor it will be less directional. Maybe I need the ground???

I was mostly doing this project for a shortwave receiver.

But on most all bands 160-20 I’m at s20 noise, lots of static. This am I tried using a common mode choke just where the coax enters the shack and no significant difference.

The feedpoint of the end fed 80m is about 30’ from the beverage and all enter the shack at approximately the same area.

So I don’t know why this beverage is so noisy.

[W1VT]

A Beverage needs to be terminated otherwise it is just a low long wire antenna.
Properly done, a Beverage has a unidirectional pattern that reduces noise pickup in other directions.

There are four ways of reducing noise in antennas.  One is to make the antenna directional.
The second way is to move the antenna out of the near fields of local noise sources.
The third way is to orient the main lobe of a beam so that it does not pass through as many noise sources as is practical.  Lateral movement may help.
The forth way is to eliminate all common mode noise pickup.  Most commonly a choke at the feedpoint.
A large radial system may also shunt noise to ground.  A ground rod often doesn't do much for noise supression.

[N1UR]

If you have S9 +20db noise on a beverage, any beverage, terminated or not, you have some kind of a feed line issue or close by noise being coupled to the bev wire. 

All of what W1VT said is right.  But starting at S9 +20db noise this is a major issue, not minor cutting and pruning.

Ed  N1UR

[W1JPP]

If you have S9 +20db noise on a beverage, any beverage, terminated or not, you have some kind of a feed line issue or close by noise being coupled to the bev wire. 

All of what W1VT said is right.  But starting at S9 +20db noise this is a major issue, not minor cutting and pruning.

Ed  N1UR

I did just terminate it - I only had a 300ohm resistor, wide braid to ground rod - no real change in noise...

I think what I will do next is just kill all house power, power the rig with my portable battery, and see what happens to the noise...OR...

Just interesting my other two antennas are not picking up this noise...perhaps just the change in feedpoint for the beverage, which is closer to the living room,  is close to something with lower power. not able to get into the other antennas, is causing the static...so maybe i'll trying moving the feedpoint and see what happens

[WB6BYU]

Your neighbors don't have an electric fence, do they?

[W1JPP]

Your neighbors don't have an electric fence, do they?

Not that I’m aware of. A pretty confident no.

Tomorrow I’ll try shutting the house power down and see if that impacts the noise. At least narrow down to my house.

[N0GV]

Step 1: disconnect feedline and terminate it w a matched dummy load. Noise goes away and it is a radiating source being picked up by the antenna.

Step 2: Use a portable SW radio and walk the antenna path looking at noise. If it is constant or low then it is phantom noise from your shack.

Step 3: If you can pinpoint the noise with the SW radio, fix it. If it isn't showing up on your 80m and other antennas it probably is NOT radiated noise from an electric fence as that is broadband.

Step 4: Check to be certain that the feedline is not near a windmill, solar inverter micro array or an electric motor. Solar water heater pumps can be noisy....

Also you can check at night for corona discharges on power pole insulators if the moon is not up. Use a pair of binoculars....

Hope this helps,

Grover

[VR2AX]

Just to add another possible test. Swap the feed/end points have the beverage and check the noise level with the feed point at the tree end.

[W1JPP]

well after swapping lines, rerouting the antenna etc...

I gave up on my beverage, as no mattrer what I did I would get a 20 over 9 rapid static, that none of my other antennas have...I even tried just a simple dipole (remember its just for listening) same issue...

I narrowed it down to the 9:1 transformer I made...I have no idea what I did wrong, but for whatever the reason when I swapped that out with a home made 1:1 balun, the sound/static went away and it listened just like my other antennas I use for rx/tx. If I put the 9:1 unun on my other antennas, I'd get the 20 over 9 rapid static...

But I did manage to get some wire up over an 80' tree with the help of my bow and arrow...and its working fine for my shortwave listening...

[WB6BYU]

I narrowed it down to the 9:1 transformer I made...I have no idea what I did wrong, but for whatever the reason when I swapped that out with a home made 1:1 balun, the sound/static went away and it listened just like my other antennas I use for rx/tx. If I put the 9:1 unun on my other antennas, I'd get the 20 over 9 rapid static...

The 9 : 1 unun is explicitly NOT a balun, in that it doesn't
isolate the coax shield from the antenna feedpoint.  If the
noise is picked up on the coax shield from something in
the house, you'll hear it without a balun.

One thing you might try is to wind a balun transformer
with an isolated input link, rather than as an autotransformer
(a single winding with a tap for the feedpoint).

Otherwise, a 1 : 1 current balun / feedline choke between the
9 : 1 transformer and the main feedline to the shack should
quiet things down a bit.