I completed my WAS on 2m back in the 80's - #116, using believe it or not,
six Cushcraft Jr. boomers. No mods, still the trigonal reflectors. I had a
98% success rate. Is this fantasy?? No, I had designed a way to spin the
entire array for polarity.
I used a torpedo top section of Rohn 25 and a straight 10' section with a
base plate. I mounted a Ham4 rotor to the base plate and ran the mast up
through the torpedo top and attached it to my H frame. This assembly sat on
a bearing, think of how a teter-toder works, when one side goes down, the
other goes up. I used a 12v ATV winch to pull down on the back and this
caused the array to elevate, the HAM4 rotor rotated polarity. At that time
sequences were 2 or 2 1/2 minutes and if the other station was there,
within the first sequence I could find them by rotating polarity.
The reason I digress is there are two ways to make a contact off the moon,
have so much gain that faraday doesn't matter or have a smaller array and a
way to adjust for polarity ( or just wait for polarity to get in your
favor!!). Lots of folks run dual polarity systems, this gives either
horizontal or vertical and using programs like MAP65 with the proper
software and hardware, you can "see" all polarities. 4x 17 ele antennas on
2m is a BIG array and requires a hefty elevation and azimuth rotor.
The digital modes have really reduced the size of the array needed to be
successful off the moon but faraday will always be there and newbies should
get discouraged if they don't work 50 Q's the first night with a single
yagi !!!
Terry Price - W8ZN
Directive Systems and Engineering
703-754-3876
On Fri, Sep 27, 2024 at 9:17 AM Zack Widup <w9sz.zack@gmail.com> wrote:
> Hi Joel,
>
> What kind of antenna system are you using on 144 MHz?
>
> Bob KH6O (now an SK) had a large array of helical antennas for EME on 432.
> It looked like a giant box spring. He sent me some photos years ago.
>
> 73, Zack W9SZ
>
> On Fri, Sep 27, 2024 at 7:34 AM <w5znjoel@gmail.com> wrote:
>
> > Hello Ev,
> >
> > I operate EME on all of those bands (current and "back in the day) plus
> > 222 MHz. Of course, the best person to get feedback from for the type of
> > operating you're inquiring about would be Peter, KA6U. Also Gene KB7Q.
> >
> > 144 MHz will have the most activity, followed by 432 then 50 MHz. With a
> > small portable station you will have to use the digi modes. The 2-meter
> > folks still hang on to JT65B, the 50 and 432 gang use Q65.
> >
> > When Farraday rotation is not in play I can work a single yagi station
> > with 100 watts on 144 and 432. 6-meters is more difficult as you will
> need
> > some power with a single yagi.
> >
> > Chat with Peter or Gene, they can tell you more than you probably want to
> > know about portable EME operating !!!!!
> >
> > 73 Joel W5ZN
> >
> > 50 MHz - 4x7 LFA 1.5KW
> > 144 MHz 4x17 1.5 KW
> > 222 MHz 4xFO15 1.5 KW
> > 432 MHz 8xFO25 1.5 KW
> >
> >
> > -----Original Message-----
> > From: VHFcontesting <vhfcontesting-bounces+w5znjoel=
> > gmail.com@contesting.com> On Behalf Of Ev Tupis via VHFcontesting
> > Sent: Friday, September 27, 2024 6:47 AM
> > To: VHF Contesting eMail Remailer <vhfcontesting@contesting.com>
> > Subject: [VHFcontesting] 6m, 2m, 70cm EME
> >
> > Of the 6, 2, and 70cm bands (those that are most likely to be in a modern
> > HF+ radio), which band has been shown to support EME with the least
> overall
> > ERP? I'm thinking "portable EME" where it isn't possible to transport
> big
> > antennas or a generator to have a kw amp. :-)
> >
> > Assume that this portable station would target QSOing with only the "top
> > tier" of well equipped DX stations.
> >
> > I'd be interested in only recent experience rather than "back in the
> day".
> > Also interested in both CW (human decode) and FTx (machine decode) modes.
> > How little power and antenna (ERP) has been successful in making EME
> > contact(s) and on what band/mode?
> > _______________________________________________
> > VHFcontesting mailing list
> > VHFcontesting@contesting.com
> > http://lists.contesting.com/mailman/listinfo/vhfcontesting
> >
> >
> > _______________________________________________
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> >
>
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