160 Meter Inverted Vee

[KM5PS]

My question is - Should I put a coax choke-like a ugly balun- on my inverted vee antenna.  I am having trouble with it interfering with my Beverage antenna.  What I mean is when I transmit above 50-100 watts of pwr it I hear my rx antenna board clicking in the back of my K3.  I figure the rig is protecting itself from receiver overload.  It only does this on 160 meters.  My Beverage antenna goes from the base of my tower to the northeast 1000 ft.  My 160 inverted vee goes from the SW to NE.  The center of my inverted vee is at 75 ft on twr.  I have tried moving the NE leg more to the north and also to the SW.  I can use 100w and no problem but get much over that, my rig starts to make a clicking noise which is coming out by the KIO3 board on the k3.  I am using an AL 811H amp.   I was trying find out what I might do to help this problem.  I am assuming that the Beverage is in the RF field of the antenna.  I am planning on checking the resistor at the end of the Beverage to make sure it is not blown this wknd.  I am feeding the inverted vee directly from the coax no balun at the moment.  Any suggestion wud be great!!  Trying to get ready for upcoming 160 meter contest in December.

Thanks
John

[W8JI]

Your antennas are too close, John. You will play heck getting a null deep enough.

The best solution by far would be to shorten the Beverage and move the feedpoint of the Beverage away from the house.  Even 650 feet long is nearly as good as 1000 feet, and will probably be much better for noise level in the Beverage because it will be away from the tower and house.

[K2MK]

Rather then trying an antenna modification that might not work, consider adding a cutoff relay to your receive antenna. There are two places where you can access a transmit indication from the K3. One is the KEY OUT jack on the back of the K3 which may already be in use for an amplifier. Another is pin 10 of the ACC 15 pin connector. The former is rated for 5 amps while the latter is rated for only 10ma.

There is also a $38.00 RF limiter available from ICE that may solve the problem. Model 196.
http://www.iceradioproducts.com/rfswitch.html#1

73,
Mike K2MK

[N3JBH]

I wonder how well that limiter thing really work's ?  It sounds like a inexpensive & good idea. Any one have experience or details  with them?
Jeff

[W8JI]

Rather then trying an antenna modification that might not work, consider adding a cutoff relay to your receive antenna. There are two places where you can access a transmit indication from the K3. One is the KEY OUT jack on the back of the K3 which may already be in use for an amplifier. Another is pin 10 of the ACC 15 pin connector. The former is rated for 5 amps while the latter is rated for only 10ma.

There is also a $38.00 RF limiter available from ICE that may solve the problem. Model 196.
http://www.iceradioproducts.com/rfswitch.html#1

73,
Mike K2MK

Let's think about this. He said:

My question is - Should I put a coax choke-like a ugly balun- on my inverted vee antenna.  I am having trouble with it interfering with my Beverage antenna.  What I mean is when I transmit above 50-100 watts of pwr it I hear my rx antenna board clicking in the back of my K3.  I figure the rig is protecting itself from receiver overload.  It only does this on 160 meters.  My Beverage antenna goes from the base of my tower to the northeast 1000 ft. 

My advice would be to get the Beverage away from transmitting antennas and tower. Here is why:

1.) 1000 feet is pretty much a waste of wire length. Earth losses under the antenna would make current at the far end almost nil.  You'll actually do better with it between 600 and 800 feet long for 160.

2.) If you brought the end to the tower, and near the HF antennas, you are working against the goals of the Beverage. You g brought the end right near where it will couple to everything and pick up noise. Even 200 feet from a resonant 160 antenna can be a problem for a Beverage, in some cases.

3.) If you disconnect the Beverage, better be sure it always works. It takes a heck of a signal to trip the relay in the K3. I have RX verticals 200 feet from my TX antenna, and I can light a neon bulb on those antennas, and they don't trip the relay in my K3.

If it was my setup, and I had a Beverage attached to a tower and right under TX antennas, I'd move the feedpoint even if it was not bothering the receiver. That's just a bad way to install the Beverage. At least get it 100 feet or more from the tower.

73 Tom

[W0BTU]

Tom is 1000% correct, John. Running your Beverage all the way to your tower is one of the worst possible places to put it. It will screw up the operation of your Beverage big time.

And you are very lucky indeed that your receiver was not damaged!

I once put a receiving antenna too close to my 70' tower, and found that it was picking up signals re-radiated from the tower itself. You absolutely need to get that Beverage well away from the tower and your inverted-vee. Even then, you may need to de-tune the transmitting antennas during receive.

Once you move your Beverage, I suggest you think about shunt-feeding your tower against a decent radial system. Unless you can raise your dipole MUCH higher than you have it now, a vertical or inverted-vee will give far better DX results on 160. Think about it: 160 is very close to the AM broadcast band, and no AM station uses dipoles. Low dipoles are for close-in work, but for DX on 160, you need a good vertical transmitting antenna. See http://www.w0btu.com/160_meters.html. If it were me, I would think about a good switching arrangement so that you can switch back and forth between the dipole and the tower (or inverted-V) that detunes the unused antenna.

[KM5PS]

Today's work on Beverage and antenna.  I have shortened the beverage down abt 250 ft.  It is now approx.  25-300 ft away from twr now.  I have also put my 160 inverted vee back on tower, but used a coax choke also on antenna.  From the test so far, everything is okay.  My relay on my receive antenna on the k3 is not tripping now.  So hopefully problem is solved.  I would like to thank everyone who responded and for the idea's.

73's
John
KM5PS

[W8JI]

Good going. You really want the Beverage to be that far from TX antennas John. The Beverage should work better.

[KM5PS]

I do believe that the Beverage is working better now. Thanks for the help.  Spent most of the afternoon changing things up.  Hope the Beverage is worth it.  HI HI ..
Thanks again for the help.  These forums are GREAT!!

73's
John

[W0BTU]

Sounds like you just have a single Beverage. All you need now are more of them. And you might as well make them bi-directional like these: http://www.w0btu.com/Beverage_antennas.html :-)