delara news Delaware Amateur Radio Association, Delaware OH   VOL 37 NUMBER 11

Tech

The Magnetic Loop - by hand!

Richard Robbins, WA8RR I joined DELARA last week..been a ham for a year and half.  I have an ICOM 7300 and a long wire chameleon.  Several 6 meter antennas and a 2M/70cm antenna in the attic. I spend most of my time on digital modes.  ( not cw ). I started playing with magnetic antennas after reading an article.   I don’t think magnetic antennas will displace my current antenna..However when we go to the Florida condo, it might provide a suitable alternative. I called a local refrigeration company and they supplied a 10 foot piece of ¾ inch copper…I did a poor job of making a circle…however not sure perfect makes a big difference.  I found a variable capacitor at the Columbus ham fest…$5. I put the thing together and along with a simple drive loop and with my RigExpert got a resonance in the 20 meter band.  The antenna will handle 100 watts. Using PSK reporter, the antenna seems to reports from north and south America and northern Europe.  I have made a lot of contacts…FT8. Since tuning is an issue, I found a two channel remote on Amazon so I could drive a small motor forward and reverse.  Found a small PWM motor controller so I could fine tune the antenna from the basement. I would like to rebuild the antenna..I am looking for 10 foot 1 or 1 ½ inch copper tube preferably bent into a circle.  ( I understand that if you fill the tube with sand, it will eliminate kinks. ) Any assistance would be appreciated. I included a picture of the antenna in its current state…It won’t win a beauty contest…but the other picture shows the nice SWR for FT8 on 20 meters WA8RR