How Did You Radio Today?

Discussion in 'Ham Radio Discussions' started by VK4HAT, Aug 11, 2018.

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  1. VK6ZGO

    VK6ZGO Ham Member QRZ Page

    Dunno, but it did it again!
    I think I'll just give up & use "my postings" or "recent activity" to fmd this thread each time.

    PS:- I found out what happened!
    Either it was "finger trouble " with the iPad touchscreen, or the website unilaterally decided it would be a fun thing, but I found it had VK4HAT on "ignore".
    Sorry, Rob!
    Last edited: Jun 26, 2020
    VK4HAT and WZ7U like this.
  2. N1BCG

    N1BCG Ham Member QRZ Page

    With all the Sporadic E hullabaloo, I thought I'd try my hand at a simple coax fed 6M dipole with broadbandedness in mind. Two challenges were immediately apparent in that dipoles *should* yield a 1.5:1 SWR at best when used with coax due to the inherent mismatch, and when starting with a mismatch, the useful bandwidth is decreased because you arrive at your "never exceed" SWR points much quicker.

    I also don't believe in using tuners at the transmitter end of coax feedlines to "make everything right". It's like painting over dry rot.

    However, adding a matching circuit at the antenna feedpoint can yield great results with the understanding that the element lengths are going to be different from the calculated lengths, but this always seems to happen anyway.

    To make a long and tedious story short (this could also have been an hour long YouTube video), let's cut to the chase...
    6 Meter Dipole.jpg

    The radiators were made from solid copper insulated household wire with great care given to proper color coding. The inductor ended up being the equivalent of 10 turns wound on a 1/2" diameter with the shield of the coax and one radiator connected at one end and the center conductor connected at the six turn point. Four more turns are from that point to the other
    radiator. The radiators are not of equal length because of the loading effect of the inductors.

    6 Meter Dipole 2.jpg

    6 Meter Dipole 1.jpg 6 Meter Dipole 3.jpg

    What I ended up with is a perfect 50Z j0 feedpoint very close to 52.0 MHz (52.037 MHz for those who like precision) and less than a 2:1 SWR at 50.0 and 54.0 MHz. Adding about 1.5" to the shortened radiator brought the resonant point down near 50.313 MHz which might be of interest to the FT-8 jockeys.

    Using 1/2" copper tubing would certainly have made the antenna even more broadbanded due to the greater surface area of the piping compared to the relatively narrow wiring.

    That might be my next step.
    W2BTK, VK4HAT, WD5GWY and 4 others like this.
  3. W4NNF

    W4NNF XML Subscriber QRZ Page

    Didn't get on the air this morning...time to start loading up for FD! :)

    VK4HAT likes this.
  4. VK4HAT

    VK4HAT Ham Member QRZ Page

    Lol sometimes that could be a good thing.
  5. N3MCZ

    N3MCZ Premium Subscriber QRZ Page

    Did a Zoom call with a new ham to help him get his new D74 programmed. He was on Facebook saying he was very frustrated that he couldn’t get it on the air.

    Got him on his local D-Star machine, and showed him how to use it. He was a much happier camper when we finished.
    WD5GWY, AD5HR, W7TCT and 2 others like this.
  6. WZ7U

    WZ7U Ham Member QRZ Page

    Sitting on 50.125, enjoying the static. That's what I'm doing for Field Day as 1E.
    VK4HAT likes this.
  7. AD5HR

    AD5HR Ham Member QRZ Page

    6 is opening, just worked WB0MPH in Pierre SD.
    Hearing others just above the noise.
    VK4HAT likes this.
  8. W7UUU

    W7UUU Super Moderator Lifetime Member 133 Administrator Volunteer Moderator Platinum Subscriber Life Member QRZ Page

    10 CW is wide open from WWA to NFL / SE Coast

    VK4HAT likes this.
  9. VK4HAT

    VK4HAT Ham Member QRZ Page

    making any contacts Eric?
  10. VK4HAT

    VK4HAT Ham Member QRZ Page


    Who would have thought this thread would last 200 pages and 2000 posts.
    AF7XT likes this.

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