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jimvw57

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

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Topic Created Posts Views Last Activity
FMJ antenna Jan 21st, 15:48 2 519 on 25/1/20
440 copper loop antenna Apr 7th 2019, 21:51 3 1,025 on 21/4/19

Latest Posts

Topic Author Posted On
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. **
440 copper loop antenna jimvw57 on 21/4/19
Got the second one done and mounted on a yardstick for some testing. Works quite well. I now have them mounted ona 1/2 length of PVC tubing and ready to mount outside. Too many other projects but it seems to be working quite well. Next step is to set up a reflector and try to make it like a beam.
2 Meter Slot-Cube Antenna (QST Jan 2019) K1AWC on 21/4/19
I used hose clamps so I could adjust where they are positioned. Easier to tune
440 copper loop antenna jimvw57 on 10/4/19
have the first one done, SWR is running at 1.1 to 1.3 starting n the second one so I can run a pair wired in parallel for higher gain

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