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+--- Thread: Antenna options for 12M and 17M ?? (/thread-7.html)
Antenna options for 12M and 17M ?? - VK4ADC - 09-09-2016
I had my first real taste of 17m operations earlier this year when I went to Norfolk Island and operated as VK9NU ( http://www.vk9nu.net ) . There were times when 20M wasn't open, neither was 15M yet 17M was. My attempts to work on 24MHz / 12M failed due to no real propagation yet the gear / antenna worked on that band.
My home QTH antennas didn't include 18MHz or 24MHz directly at that stage so I started planning something after my return. The outcome was interspersing two extra elements on my Cushcraft A3S tribander boom. More details at vk4adc.com
There are few ideas around other than dual band trap wire dipoles or two or three element yagis just for 18 and 24 MHz. That leads me to ask: What antenna options have you in place for these two bands ??
Doug VK4ADC
Re: Antenna options for 12M and 17M ?? - VK3XL - 12-09-2016
Doug, I made a dual band vertical and mounted it on the shed roof (shed is 24ft x 40 ft, so its a big roof. Have not used it much but when the band is open it seems to work ok for me. The vertical was made as a aluminium tube for 18Mhz with a wire spaced approx 250 mm off the side for 24mhz. The wire connects to the bottom of the aluminium tube at the feed point.
Re: Antenna options for 12M and 17M ?? - VK4ADC - 12-09-2016
Mike
I used a homebrew multiband trap dipole/V when I was on Norfolk but I wanted something that I could point rather than being omnidirectional. To me a vertical = noise from anywhere and I have spent enough resources setting up this QTH that I didn't want to go down that track. By the same token, I didn't have enough space on either tower to put up yet another yagi just for 18 and 24MHz. The new interspersed trapped elements for 12M and 17M seemed the best that I could come up with.
The 'parallel whip' idea to a common feedpoint does work but the spacing of the two elements is fairly critical and needs to be significant (>300mm) if you want to reduce the interaction. I tried that idea a couple of years ago while experimenting with a 20/15/10 arrangement and ended up abandoning it due to the spacing requirements needed and looking for something physically stable. I still have the basic hardware setup somewhere in the pile of aluminium tubing near the shed
Thanks for the input. Anyone else??
Re: Antenna options for 12M and 17M ?? - VK4WDM - 13-09-2016
"There were times when 20M wasn't open, neither was 15M yet 17M was"
I have noticed that to be case a number of times during the last few months. Maybe it is a characteristic of 17m when the sunspot numbers get lower?
My Butternut HF9V vertical works quite well on 17m and my Timewave ANC-4 "noise canceller" drops the noise, as it does on the other bands (twas a very good investment
73
Wayne VK4WDM (Yes the old bloke is BAAACK)
hock:
RE: Antenna options for 12M and 17M ?? - VK3XZ - 04-07-2017
My Rotating trapped Dipole for 30, 17 and 12 works really well. It is made by Hygain sold here in Melbourne. Nice piece of Equipment and performs fantastic! 73 Mike VK3XZ
RE: Antenna options for 12M and 17M ?? - VK3AV - 05-07-2017
I have an Icom AH-4 feeding a ~41m horizontally mounted loop. Select frequency and push the Tune button. I did quite well on the SOTA 12m challenge a couple of years ago using this set up.
Regards
Bernard
VK3AV
RE: Antenna options for 12M and 17M ?? - VK6TU - 09-07-2017
(05-07-2017, 09:00 PM)VK3AV Wrote: I have an Icom AH-4 feeding a ~41m horizontally mounted loop. Select frequency and push the Tune button. I did quite well on the SOTA 12m challenge a couple of years ago using this set up.Bernard,
Regards
Bernard
VK3AV
How did you connect the Icom AH-4 to the loop?
Regards
Michael
VK6TU