CSERG EMAIL

Send email for CSERG to jushamn@gmail.com

Sunday, August 18, 2024

Conductive Fabric Ground Plane

Conductive fabric is available from Amazon. It make an excellent ground plane in place of long copper wires. Several hams in the area have used this with Wolf River Antennas with great result. It's very light weight and flexible. It does tend to get blown about in windy conditions but following are a couple of solutions for that if rocks are not handy to hold it down


Solution 1 - Grommets

I found the cloth is so thin the grommets pulled out. So my XYL sewed in these upholstery reinforcements and I redid the grommets. I use fishing weights on carbineers to hold the cloth on the ground. Very fast setup and flattens out my SWR across the bands with my WRC and 17' whip. de KJ8MRH 


Solution 2 - Bias Tape Edging

I had my wife sew bias tape along the edges. She cut the tape several inches longer than the cloth then folded it back and stitched it to form a loop that could be used with stakes.


I have used this with my home brew 1/4 wave length vertical on 15 meters. I got S7 and better signal reports from Texas, Kansas, California, Virginia on SSB. Mat is only 42 X 58 which is fine for 15 meters and up. I'd recommend getting a larger piece if you plan to work on lower bands.


Wednesday, July 24, 2024

UPDATE: UPPING THE PERFORMANCE OF YOUR HT

Hi All

I ran some tests on tiger tails. I noticed in the video that he did not test a tiger tail with a rubber duck antenna. All the antennas he tested were quarter wave.

I decided to run some tests of my own. I have yet to do any field tests. I don't have an instrument to check field strength as he did in the video. 

I ran the tests using my NanoVNA.

First, I checked the SWR on 2 quarter wave whips and three rubber ducks. They were all under 2:1 SWR across the 2 meter band.

Second, I used one of the whips to tune a tiger tail made of #24 AWG magnet wire. It was necessary to use that small wire so the antenna could be screwed down all the way onto the radios, Baofeng UV-5R and Anytone AT-878UV. They both have recessed antenna connections. I was able to trim the tiger tail back to the same SWR that the whip showed without the tiger tail. 

Third, I proceeded to check the second whip. It's SWR with and without the tiger tail was also nearly the same. It did show a slight shift upward in frequency with the tiger tail. However, the SWR was still well under 2:1 across the band.

Fourth, I tested the rubber ducks with  the same tiger tail. In every case the SWR was effected so that most of the 2 meter band was higher than 2:1 SWR. One was higher than 2:1 across the entire band.

Fifth, I tried to build another tiger tail that would work with the rubber ducks. Every attempt resulted in no better SWR than the original tiger tail that I tuned with the quarter whip.

My conclusion is that tiger tails have the potential to improve a HT's performance with a quarter wave whip. As far a with a rubber duck it does not look too promising.

Come spring and better weather, I plan to run some field tests with another ham. I've yet to determine what that test will look like. But as a minimum there will be a receiver with a S-meter for making the measurements.

73,

Dave, K7PDW

Keep On Ham'n


PS: I had intended to post this much earlier but life intervened. The field test have yet to be performed either.


Monday, April 1, 2024

SCHEDULE OF MEETING TOPICS FOR 2024

Following is the schedule of topic that will be presented at our monthly face to face meeting

27NOV2024 THANKSGIVING EVE NO MEETING

25DEC2024  CHRISTMAS DAY NO MEETING

29JAN2025  LEE BARRETT  DETERMINING THE IMPEDANCE OF UNKNOWN COAX 

Meetings are held at Clearfield Municipal Center in the second floor auditorium at 8:00 PM MDT on the last Wednesday of each month.

Tuesday, March 12, 2024

Amateur Radio License Map

Lee, K7NM, shared this.

 Do you want to see who holds a Amateur Radio license with a U.S. Callsign in your neighborhood (or anywhere in the US)?

You can search by Call Sign, Grid Square, Zip Code or Street Address or you can....
Hold down the CTRL key while using the Mouse Wheel to zoom in/out or hold down the left mouse button to drag the map

Amateur Radio License Map