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HF - 10m Phone


Wayne Morris - AC5V
 

Hi,

 

Just for kicks, I got on 10m phone yesterday, Technician portion of the band. There were some South American stations calling CQ. I worked LU1DX, Argentina, on 28.477MHz. The mode is USB (Upper Sideband) of course. If you have a Technician license and want to try out HF, you can get started. A 10m dipole is easy to construct and does not take a lot of room. You don’t even have to get it very high. Just try to make sure no part of the antenna is close enough to the ground for someone to come into contact with it. 10’ is a pretty good rule for minimum high for any radiating part of the antenna.

 

There is a ton of information on the net for building antennas. Here is just one video: https://www.youtube.com/watch?v=84F4UgSWmQoy

You also have digital privileges on 10m. I operate FT-8 95% of the time. I have 78 contacts on 10m since 10/23.

 

You may not be an electrical engineer and homebrew your own transmitter/receiver, but you CAN build your own antenna!

 

Need help? OK! We have the Elmer Net on the repeater 147.16 at 7pm Tuesdays. You can ask anything you like. You can also email me at AC5V@.... Don’t want to build one? OK, everybody and their dog sells them. You can go to one of the commercial sites or try eBay.  You need some coax to connect the antenna. Other than that, the parts are as simple as you want them to be. You need an insulator in the middle to hold the two ends and support the antenna two insulators for the ends of the wires, and some rope to hold the whole thing up. You can, but you don’t have to, get a 1:1 center isolator to make building easier but back in 1978 when I was licensed, I never hear of one of those. We used three ceramic insulators, one in the middle and one at each end. The antenna wire was whatever stranded copper wire we had available (interpreted as cheap).  We used the formula 468/f MHz as the starting length and added a couple of feet for attaching the wires. Then we cut that in half, connected one to the shield and one to the center conductor of our coax, usually RG-58 back then. A dab of silicone and some electrical tape sealed up the coax. The antenna wires were then connected to each end of a ceramic insulator. The coax was wrapped around the center insulators and tied. Zip ties will work fine for holding the coax. Sometimes, we make a choke by coiling about 8 turns of coax at the antenna on a 6” form (we used a coffee can but who has those anymore?)

 

The antenna always needed to be trimmed. The far end of the wire was looped through a center insulator an wrapped back on itself. The other side has a rope tied.

 

We hauled the whole think into the air from the center where the coax was, just tie a rope on the insulator. Then, we just checked the swr at the frequency we wanted with our radio using about 5 watts (antenna analyzers would be a pipe dream). It was usually higher than we wanted. Then move up 10KHz and check it again. If the SWR went down, go up another 10. If the SWR is higher, go down 20KHz and try. The SWR should go down. If the swr is lower at a higher frequency, the antenna is too short. If the swr is lower at a lower frequency, the antenna is too long. After each test, we adjusted the length of the antenna by untwisting antenna on each end and lengthening or shortening the antenna then retesting. We did this until we had the lowest swr we could get at the desired frequency.

 

This was very inexpensive to get on the air. Some people made multiple antenna wires and used the same feedline, they just lowered the antenna, connected the wires they previously tuned and raised the antenna again. If you has a 20m and 40m dipole, you could work 20m in the day and 40m at night.

 

I don’t have the insulators anymore (they are available at hardware stores in the electrical department) but I had an old plastic cutting board. I took a saw and drill  and made a center insulator and end insulators for one of my antennas. With a little imagination and scrounging around, you may not even have to buy anything – maybe some coax.

 

So, the bands are working pretty well and seem be improving by the week. If you have the radio equipment, you can get on the air.

 

I will  be glad to get on the air with you. Just let me know.

 

 

 


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73s,
Wayne, AC5V