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jimvw57

Joined: Sat, Dec 16th 2017, 15:23 Roles: N/A Moderates: N/A

Latest Topics

Topic Created Posts Views Last Activity
ZS6BKW build Dec 13th 2020, 23:05 5 130 3 weeks, 1 day ago
FMJ antenna Jan 21st 2020, 15:48 2 633 on 25/1/20
440 copper loop antenna Apr 7th 2019, 21:51 3 1,133 on 21/4/19

Latest Posts

Topic Author Posted On
ZS6BKW build jimvw57 3 weeks, 1 day ago
Been working well using an auto tuner, my latest issue was a squirrel that for some reason liked to chew through the cord holding up one end. We had a discussion and my flying pliers won. no more problems with that rodent!!
ZS6BKW build jimvw57 on 14/12/20
Ok, so it occurred to me that I did not measure the length of the ladder line, and it was much longer than I thought. I cut it back to the recommended length, straightened it out and antenna is now working as it should. Measure twice, cut once... Thanks!!!
ZS6BKW build jimvw57 on 13/12/20
Ok so I am working on building this antenna, got both wires at the correct length, added the ladder line and coax, the tuning is off the scale. It may be possible the ladder line is too long, it had tape on it saying it was 39 ft long but that may not be right. Seems a lot longer than that. also I have a looped up section as it seems too long, does that affect my swr readings?

I can only get it roughly 25-30 ft off the ground due to location problems. Could this be causing issues too? Trying to learn as I go...
FMJ antenna jimvw57 on 25/1/20
No replies so here is what I figured out.
The guys at Alpha antennas are in Puerto Rico working with earthquake recovery efforts.
The 'coupling' at the base of the aluminum mast is actually made of brass. I drilled it and used a Heli-coil that I shortened to fit, seems to be working just fine now.
FMJ antenna jimvw57 on 21/1/20
I purchased an Alpha Antenna portable antenna, The FMj model for home and cabin use. I figured the portable feature would work out good. Been thrilled with the operation and the ease to setup and take down the antenna. Unfortunately it doesn't handle wind gusts as nicely as I would like, and has blown over a few times. The aluminum antenna has developed a problem with where it threads into the coil. it has about 1/2 turn of threads left and it is quite fragile. The base of the mast looks to be a 3/8-24 coupling and I am wondering if it can be removed and replaced. Not sure how it is attached to the aluminum mast
I have tried to contact Alpha Antenna but have not gotten through to them yet. I would like to use this for a QSO event this weekend, and I guess I will drill the coupling and install a Heli-coil insert to make new threads.
Anyone have a better idea?? thanks

*** keep in mind that this was not a defect, but the result of winds blowing the antenna over. It should have been better secured before the winds hit. **

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