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Antennas / Re: EFHW sloper array?
Last post by N0AJS - November 10, 2020, 10:37:56 pm
 ive noticed that every time I setup my EFHWs they tend to favor the obtuse angle.   So if im "aiming" for a certain direction i tend to follow this rule. I have been very successful when i set up on the bank of a large pond or lake getting more radiation off the acute side. Water makes for a good ground plane and will help reflect the unusually low takeoff angles present on the backside of a sloper.
Antennas / FT-82-43 EFHW
Last post by N0AJS - November 07, 2020, 12:55:11 am
Taking Gil's idea for using an 82 toroid I built this 64:1 transformer. Although the 3D printed box is a much more efficient use of space, I don't currently own a printer. I did find that a Hammond 1551HBK is about as good as it gets as far as size and ruggedness. The overall dimensions are 60x35x20mm. This does not have a ground connection but i have found that a small coil in my coax generally takes care of any RF on the shielding.  You cannot see attachments on this board.
Antennas / Re: EFHW sloper array?
Last post by Lamewolf - November 02, 2020, 09:35:21 am
I used an EFHW sloper on 60 meters using a 49:1 transformer at the feed point that was at 7' and the far end of the wire (88') was 70' high in a tree.  Radiation was somewhat directional toward the feed point which was pointed toward the west.  But it did give good all around coverage too and had a flat swr of about 1.2:1 on all 5 channels.
Antennas / Re: Easy to Make Doublet for Q...
Last post by Lamewolf - November 02, 2020, 09:31:45 am
I made a similar antenna for portable operation but I made my elements 44' long for a total doublet length of 88' and fed it with lightweight 300 ohm TV twinlead and my little homebrew Zmatch tuner for 10 thru 80 meter coverage.  The wire elements on mine was made from insulated #20 speaker wire.
Antennas / Re: End fed windom
Last post by Lamewolf - November 02, 2020, 09:21:14 am
I built a Windom, but I prefer the term "Off Center Fed Dipole" and I have no issues with RF because I also incorporated a good CMC choke in the same box with the 4:1 balun - works super good !  Initial resonance is set to 3.450 mhz to get 40, 20, 17, 12, 10, and 6 meters as close as possible, then I use a capacitor with a bleeder resistor across it for protection to move 80 meter resonance up the band without effecting the other bands.
Antennas / Re: Balanced Line Linked Dipol...
Last post by Lamewolf - November 02, 2020, 09:12:53 am
If you are feeding a dipole with ladder line, skip the links and just make it a half wave on the lowest band of interest and use a 1:1 current balun at the end of the ladder line with a short coax jumper to the tuner.  An 80 meter dipole fed with ladder line this way will work 10 thru 80 meters and is a very efficient antenna !
Antennas / Re: S8 noise at the QTH, need ...
Last post by Lamewolf - November 02, 2020, 09:04:36 am
Don't use an AM broadcast radio as electrical nose can travel several hundred miles at those frequencies.  Instead use a scanner set to the aircraft band 116 to 136 mhz AM where the noise only travels a few miles.  Or if you have a portable rig such as the Yaesu FT-817 that will do  2 meter AM, use that.  A 2 meter, 3 element beam can be used and bought commercially or easily built.  Even a simple dipole made from stiff wire such a coat hanger wire.  You could even make a quick and easy 2 meter, 2 element beam with coat hanger wire and use a piece of 1 x 2 inch wood for the boom.

Antennas / Re: EFHW observations and radi...
Last post by Lamewolf - November 02, 2020, 08:40:08 am
Stations only 50 miles away require NVIS propagation many times, so deploy your EFHW low to and horizontal to the ground, or as an inverted V with the center of the wire about 20 feet high and the ends about 3 feet high.
Antennas / Re: S8 noise at the QTH, need ...
Last post by N0AJS - October 17, 2020, 12:50:27 pm
Well, i did some basic investigating and tracked it approximately to a pole a block from the house. Called the utility company and they sent a lineman to talk to me. He looked around and found a capacitor bank ground wire was touching metal and causing the buzzing. He was really surprised that i was able to track it down and had mentioned how they usually dont find the issue if they get a call. Om still thinking about building a DF antenna and some sort of an attenuation box just for situations like this. Maybe even build a fox transmitter and get a local fox hunt going.
Antennas / Re: S8 noise at the QTH, need ...
Last post by Sparks - October 12, 2020, 09:45:04 pm
Since you live in the US, maybe you could complain to the FCC and let their inspectors find the cause?

Another possibility:

QuoteElectrical interference may also be caused by power lines. Interference caused by your power company's electrical equipment is normally continuous, and your power company should be notified.

A simple method of determining the location of electrical interference is by using a portable battery-powered AM radio tuned to a quiet frequency at the lower end of the dial. You should hear static or a buzzing sound as you get close to the source of the interference. The closer you get, the more intense the static will be.

If you cannot locate the interference source in your own house, check with your neighbors to see if they also experience interference. The source may be in their home.

If you cannot determine the source of the electrical interference, contact the customer service department of your local power company. Most power companies will investigate the problem and take steps to correct it.
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