Hello everyone, I moved to an apartment so the big old dipole I'd been using had to go. I whacked together a simple magnetic loop antenna over the weekend using a 3kV open-air capacitor and some (very thin) refrigerator copper tubing.
I can receive, and the tuning cap indeed does its job, but I have only managed one very weak contact on transmit.
I have two main questions:
MOST IMPORTANTLY: When I begin to TX, I turn down the output power on my Icom IC-737 to the minimum possible, throw it in AM, and tune for 1:1 swr. This is always possible on the 20m band (1:1). Only after checking and re-checking that my SWR is <<1.5 do I switch back to SSB and turnh up the juice. Is this the safe, best practice for using a magnetic loop? I don't want to unwittingly damage my 737. When I use AM and turn the power up to the full output, I noticed that there is a brief arc across the cap plates, so I no longer turn it up all the way, though I have never seen arcing in SSB even with full power and full modulation under test. What effectg could arcing have on my transmitter if it is noticed immediately?
SECONDLY: Presumably, based on the pacific66 calculator, I am getting very poor efficiency due to the tubing I used being about 0.5cm in diameter. Is it worth it for me to use that thinner tubing as the faraday fed loop, and then go buy the proper length of 3/4" or greater copper coiled tubing?
Any general magloop info is welcomed here. I have read everything pertaining to magloops in the archives and a lot of the information is contradictory or too introductory.
(I am licensed btw, I just prefer to remain semi-private) Thanks everyone!
Submitted June 24, 2015 at 02:40AM by SpoopyLoops http://ift.tt/1JhjzN0 amateurradio
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