Saturday, May 03, 2014

QRPttF 2014

Today was QRP to the Field for 2014, and it was also my birthday. What a present! Although I didn't get to spend anywhere near as much time on the air as I would have liked, I got a little air time in and that's always a good thing.

The theme for today was Tres de Mayo in honor of Cinco de Mayo. Well, here in New Jersey there really aren't an abundance of locales with a Mexican flair. So I got a little creative.

Yes, I placed some Chipotle Mayo next to me while I operated.

I got to experiment a bit too. I used both my Par EndFedz and the EARCHI 9:1 Unun with a 36 foot radiator. The Par EndFedz performed as expected. The EARCHI performed much better than last time. The extra three feet of wire made a big difference. The KX3 handled the wire well on all bands, 40 through 10 Meters with minimal clicking and clacking from the auto tuner.

In the hour or so of operating time that I got in, I worked about a dozen or so stations. Included were some very familiar calls like Mert W0UFO, Jerry N9AW, Rick NK9G, Dave AB9CA, Gene N5GW and Kelly K4UPG among others.

So even though I didn't get a lot of operating time in, I did learn more about the EARCHI end fed. I think it will serve well as an all around multi band antenna for portable ops.

72 de Larry W2LJ
QRP - When you care to send the very least!


  1. David VE7EZM and AF7BZ12:23 AM

    You wrote: "I used both my Par EndFedz and the
    EARCHI 9:1 Unun with a 36 foot radiator. The Par
    EndFedz performed as expected. The EARCHI
    performed much better than last time. The extra
    three feet of wire made a big difference."

    I would think that the combination of a 33 ft
    radiator and a 9:1 UnUn would be very bad on 40
    meters, and probably not very good on 15 either.
    The radiator is an odd number of quarter
    wavelengths long and has low input impedance.
    Then the 9:1 UnUn reduces the impedance seen by
    the rig by an additonal factor of 9, probably to just
    a few ohms. No wonder the excellent KX3 internal
    tuner has a rough time on those bands.

    The KX3 tuner does not like very high impedance
    loads. But even with a half wave antenna, the 9:1
    UnUn should pull the impedance down to where
    the KX3 can deal with it. The other advantage of
    feeding at a voltage maximum is the high
    impedance means low curent, with low current
    likewise flowing in the (lossy) ground return or
    counterpoise. Try 66 ft or thereabouts and see
    how it works on 40. But not on 80! That band
    wants 132 ft.

    David, VE7EZM and AF7BZ

  2. Hi Larry, happy birthday to you. Hope you had a nice day. 73 Paul PC4T

  3. Anonymous7:04 AM

    Did you use a counterpoise with the UNUN and/or chassis earth ground? Thanks!

  4. David,

    I used 33 feet the first time, which did not work well. 36 feet worked much better. According to some sources that I have read, 54 feet would be ideal. A little too long for the backyard, I will try that length the next time I am at the park.

  5. Thanks, Paul! It was.

  6. I did not use a counterpoise in the classic sense. I did have a 25 foot length of coax between the radio and the unun. The shield of the coax serves as a counterpoise.

  7. Very nice, Larry. I got the significance of the Mayo right away. Very funny. I see the Simplex Mono isn't always the first choice for field operations. ha.

  8. No sir! The Simplex Mono stays in the shack. Way too nice to bring out to the field, although that would be enjoyable. That's a Viz key that I was using.

  9. Larry it was great to work you despite the poor condx and QSB. My key was out of adjustment and was giving me fits during our brief QSO. Guess all the portable ops had knocked it loose! I only got to spend 45 min on the air but enjoyed being out. We had pretty steady rain here in Orlando and it shot the day for me. By the time I got out in between showers 20m was a bit mushy, though I was hearing a OH2 and a couple G signals just above the noise. At least we gave out a few more contest points, eh? GRRRRR! I miss our PB crowds these days.
    Kelly K4UPG