Chameleon P-Loop 2.0 & A Real Shark Attack- K6UDA Radio Episode 46

Discussion in 'Amateur Radio News' started by K6UDA, Mar 24, 2017.

ad: L-HROutlet
ad: l-rl
ad: l-gcopper
ad: Subscribe
ad: l-assoc
ad: L-rfparts
  1. K6UDA

    K6UDA XML Subscriber QRZ Page

    I'm on San Salvador Island in the Bahamas testing out the new CHA-P Loop 2.0. Made a 3,000 mile QSO with Dr. Balun back in California. You also get to see a little bit of my dive trip and an honest to goodness shark attack by not one but two sharks.
    EP 46 DXpedition QRZ.jpg
     
    W4SEX, KK6JKC, KC6SOT and 7 others like this.
  2. NH7RO

    NH7RO Ham Member QRZ Page

    Well, the shark attack was neat.
     
  3. KM4CQG

    KM4CQG XML Subscriber QRZ Page

    Bob

    Next why dont you test the new F Loop with the new remote rotor and tuner.

    Glad your feeling better.

    Ian
     
  4. KB9UFE

    KB9UFE Ham Member QRZ Page

    K6UDA

    Thanks for the video. Nice job.

    Tom
    KB9UFE
     
  5. VK3CAB

    VK3CAB Ham Member QRZ Page

    Bob, a nice video and over view of your ham radio experiences on San Salvador Island.
    I've had a go at building mag loops of approximately the same dimensions as the CHA-P Loop 2.0 and I too have had disappointing experiences on 40mts. I was using RG213 with the braid and core shorted together as the major loop. I had a look into this lack of performance and found the '66Pacific' site where they had a link to an ' antenna calculator' (the site address is
    www.66pacific.com/calculators/small-transmitting-loop-antenna-calculator.aspx). The calculation showed showed that the efficiency of my antenna on 40mt was 10%. Which isn’t too good if you’re only working QRP 5Watts into it! According to the same calculator if I doubled the diameter of the primary loop to 7.2mts and tripled the conductor thickness to 30 mm the efficiency would soar to 73%. As it stands my mag loop is acceptable for 18MHz with a 76% efficiency. And these results are born out by the experiences you have had on 20 and 18mts.
    73
    Tony VK3CAB
     
  6. M6XXX

    M6XXX Ham Member QRZ Page

    Good video Bob beautiful place.
    73
    Glyn M6XXX
     
    KF4ZKU likes this.
  7. K3RW

    K3RW Ham Member QRZ Page

    That's the problem with all these manufactured loops--they aren't really right for any frequency but supposedly can cover a lot of them, even if they do it poorly on most of them.

    You might get away with a 1.5 or 2-turn loop on 40m and not have to double the size--just bundle the loop together on itself--either 1 full turn or maybe 1.5 depending on how you do it. I haven't seen a reliable calculator for that type. Uniform currents can be a challenge though.

    Loops are cool though, but far more rewarding for the homebrewer than anything I bought out of a box.
     
  8. K3FHP

    K3FHP XML Subscriber QRZ Page

    Tony, I would think a 22 foot diameter loop would be practical for portable operation. Are you thinking feet vs meters or circumference(as the calculator uses) vs diameter?
     
  9. NH7RO

    NH7RO Ham Member QRZ Page

    Are you serious? My 7-foot diameter 40M loop is just "small" enough to carry about 25 feet out into my back yard to set up! 22 feet might require a forklift of some sort!

    All of these commercial STLs that use braided coax are responsible for the bad reputation that they garner---if they would only get their act together and use solid and continuous copper or aluminum tubing with a proper vacuum variable the results would be far, far superior.

    I can't imagine ever using one of these Chameleon or Alpha or Alex Loops unless I was into digital or CW modes they are so inefficient!
     
  10. K7LZR

    K7LZR Ham Member QRZ Page

    K2MAK likes this.

Share This Page