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Re: Horizontal Polarization for VHF/UHF DX

Bill
 

Nice work Dan! I put the TAPR conference on my calendar.  Thanks.

Bill W7QQ

On Sun, May 27, 2018 at 9:01 AM, <daniel.fay@...> wrote:
Bill,

Thanks for your response. I think I will test out both horizontal and vertical polarization when I get the chance. Right now, I'm trying to finish up the basic long-distance tests so that I can submit a paper to the ARRL/TAPR DCC conference (it's in ABQ September 14-16, and the paper deadline is at the end of July). I also have an STA from the FCC to do up to 50W on 70cm for this work (the modulation technique is a form of spread spectrum, and amateur spread spectrum communications are limited to 10W by the FCC). Unfortunately, the modules I'm currently using don't let me access the RSSI information on the transceiver chips, so I'm not going to be able to get precise results for horizontal vs. vertical polarization. Eventually I hope to try a different module that gives me low-level access to the transceiver chip.

Hopefully, I'll at least make some progress and put up my 15-element 70cm Yagi this weekend.

-Dan Fay KG5VBY in ABQ


Re: Horizontal Polarization for VHF/UHF DX

Daniel Fay
 

Bill,

Thanks for your response. I think I will test out both horizontal and vertical polarization when I get the chance. Right now, I'm trying to finish up the basic long-distance tests so that I can submit a paper to the ARRL/TAPR DCC conference (it's in ABQ September 14-16, and the paper deadline is at the end of July). I also have an STA from the FCC to do up to 50W on 70cm for this work (the modulation technique is a form of spread spectrum, and amateur spread spectrum communications are limited to 10W by the FCC). Unfortunately, the modules I'm currently using don't let me access the RSSI information on the transceiver chips, so I'm not going to be able to get precise results for horizontal vs. vertical polarization. Eventually I hope to try a different module that gives me low-level access to the transceiver chip.

Hopefully, I'll at least make some progress and put up my 15-element 70cm Yagi this weekend.

-Dan Fay KG5VBY in ABQ
Re: ARRL January VHF Contest results posted

n5epa.bob@...
 

Great write-up Duffey!

From: "James Duffey" <JamesDuffey@...>
To: nmvhf@groups.io
Sent: Saturday, May 26, 2018 9:23:50 PM
Subject: [nmvhf] ARRL January VHF Contest results posted




The ARRL January VHF Contest results are now available from the ARRL website:


The NM VHF Society had a good showing, finishing 11th in the Medium Club category.  We were narrowly beat out by the AZ Outlaws Contest Club, who had 3 times as many entrants! So thanks to all who contributed to the club score. 

Jim, KC7YQ, finished top in SO3B for the Rocky Mountain Division

W7QQ with W7QQ, WB2FKO, and KG5FHU as ops, took tops in Rocky Mountain Division for the Multioperator Unlimited 

The June VHF contest is in two weeks, so start getting prepped now. - Duffey KK6MC

James Duffey KK6MC
Cedar Crest NM
Re: Horizontal Polarization for VHF/UHF DX

Bill
 

Hi Dan,

I'll add one more reason why horizontal polarization is preferred: 

As a practical matter it's much easier to stack horizontally polarized yagis on a single mast. It's important to (co-aim) each antenna such that peaking an antenna bearing on one band results in a peaked signal for all other bands on the same mast. Stacking those same antennas with vertical polarization would require more unsupported mast length. This vertical mast dimension is often at a premium.  Mechanically one usually prefers to minimize unsupported mast above the tower's thrust bearing to minimize the cantilevered wind loads.

Answer number 1; It Really Doesn't Matter is one I disagree with based on my own on-air experience.  It probably matters less if one assumes each station's polarization is consistent with others, but communication effectiveness is greatly affected by cross polarization between stations...... and not in a good way. The comment about commercial stations using both vertical and horizontal polarization does not apply to weak signal operation because commercial communication is designed to maintain an effective link margin. Positive link margin may be maintained by adding transmit power, increasing receive S/N ratio or managing the path loss and distance, the latter being the variable that weak signal DXers do not manage.

Keep us posted on your conclusions as you work through this question.

73 Bill W7QQ

On Sat, May 26, 2018 at 6:12 PM, <daniel.fay@...> wrote:
Hi Everyone,

Whenever people do weak-signal work on VHF and UHF frequencies, it's always done with horizontal polarization. I'm trying to understand exactly why in the context of some long distance packet radio experiments I'm currently performing. Looking around the Internets, I find answers ranging from "you use horizontal polarization for weak signal VHF/UHF because that's what everyone else is doing" to various justifications for its superiority. Note that I'm discussing weak-signal work via e.g. troposcatter and diffraction, and not Es, meteor scatter, or EME.

Here are some of the answers that I've seen:
  1. It doesn't really matter. ISTR one paper discussing troposcatter stations in the North Atlantic that didn't see much difference between horizontal and vertical polarization. Similarly, it appears some commercial troposcatter systems communicate using both horizontal and vertical polarization as a form of diversity.
  2. Ground gain. Horizontal polarization gives you a few db (up to ~5dB) of ground gain over vertical polarization.
  3. Lower takeoff angle. I've seen some claims about this, but I'm not at all sure if this is the case.
  4. Better diffraction. Horizontal polarization may diffract better around obstacles like hills, mountains, etc. I don't know if this is analogous to how sunglasses are often vertically polarized because glare off of objects (e.g. water) tends to be horizontally polarized.
  5. Less QRM. Apparently interference (both natural as well as man-made) on some frequencies such as 2m is vertically polarized, so horizontal polarization avoids reception of it.
I was wondering if anyone who was familiar enough with the theory behind troposcatter/diffraction communications could key me in on how much better horizontal polarization is vs. vertical polarization and whether the info I've seen is correct.

Thanks,

Dan Fay KG5VBY in ABQ


Re: ARRL January VHF Contest results posted

Jonesy W3DHJ
 

On Sat, 26 May 2018, James Duffey wrote:

The ARRL January VHF Contest results are now available from the ARRL website:

< http://www.arrl.org/files/file/ContestResults/2018/2018-January-VHF-Contest-Full-Results-Ver%201_01.pdf >
Nice write-up, Duffey! I can't even imagine how much toil and trouble
it entails to take on such a job. HI!HI!


The June VHF contest is in two weeks, so start getting prepped now.
You're preachin' to a fella with a Black Belt in Procrastination.
But, I'll show up -- that's 80%, ain't it?

Jonesy
--
<pre> Marvin L Jones | W3DHJ | W3DHJ | https://W3DHJ.net/
Pueblo, Colorado | @ | Jonesy | __ linux FreeBSD
38.238N 104.547W | jonz.net | DM78rf | 73 SK
Re: ARRL January VHF Contest results posted

Bill
 

Jim,

Very nice report!  I liked that it had a very broad perspective.  Something in it for everyone.  See you at Fina tomorrow where I'll have $$ and a battery.

I've been working with AF9O, who will rove for the June contest.  He'll have a modest station on 6, 2, not sure about 222 but 432 and 1296 for sure. He'll be in a Suby Outback and will setup/breakdown at each new op site. He borrowed a PAR Moxon from me and the remaining antennas are cheap yagis.  I've done some on air testing and Eugene has a good signal on all bands when elevated and clear of vegetation (his home QTH isn't). He's working on planning now...... probably Moriarty. Pretty fun watching him light up each new band.

Bob Darlington N3XKB Los Alimos is also now on 144 and 1296.

Bill W7QQ

On Sat, May 26, 2018 at 9:23 PM, James Duffey <JamesDuffey@...> wrote:
The ARRL January VHF Contest results are now available from the ARRL website:


The NM VHF Society had a good showing, finishing 11th in the Medium Club category.  We were narrowly beat out by the AZ Outlaws Contest Club, who had 3 times as many entrants! So thanks to all who contributed to the club score. 

Jim, KC7YQ, finished top in SO3B for the Rocky Mountain Division

W7QQ with W7QQ, WB2FKO, and KG5FHU as ops, took tops in Rocky Mountain Division for the Multioperator Unlimited 

The June VHF contest is in two weeks, so start getting prepped now. - Duffey KK6MC

James Duffey KK6MC
Cedar Crest NM
ARRL January VHF Contest results posted

James Duffey
 

The ARRL January VHF Contest results are now available from the ARRL website:


The NM VHF Society had a good showing, finishing 11th in the Medium Club category.  We were narrowly beat out by the AZ Outlaws Contest Club, who had 3 times as many entrants! So thanks to all who contributed to the club score. 

Jim, KC7YQ, finished top in SO3B for the Rocky Mountain Division

W7QQ with W7QQ, WB2FKO, and KG5FHU as ops, took tops in Rocky Mountain Division for the Multioperator Unlimited 

The June VHF contest is in two weeks, so start getting prepped now. - Duffey KK6MC

James Duffey KK6MC
Cedar Crest NM
Re: Horizontal Polarization for VHF/UHF DX

Jonesy W3DHJ
 

On Sat, 26 May 2018, daniel.fay@gmail.com wrote:

... find answers ranging from "you use horizontal polarization for
weak signal VHF/UHF because that's what everyone else is doing"
Well, there you go! :-)

Jonesy
--
<pre> Marvin L Jones | W3DHJ | W3DHJ | https://W3DHJ.net/
Pueblo, Colorado | @ | Jonesy | __ linux FreeBSD
38.238N 104.547W | jonz.net | DM78rf | 73 SK
Horizontal Polarization for VHF/UHF DX

Daniel Fay
 

Hi Everyone,

Whenever people do weak-signal work on VHF and UHF frequencies, it's always done with horizontal polarization. I'm trying to understand exactly why in the context of some long distance packet radio experiments I'm currently performing. Looking around the Internets, I find answers ranging from "you use horizontal polarization for weak signal VHF/UHF because that's what everyone else is doing" to various justifications for its superiority. Note that I'm discussing weak-signal work via e.g. troposcatter and diffraction, and not Es, meteor scatter, or EME.

Here are some of the answers that I've seen:
  1. It doesn't really matter. ISTR one paper discussing troposcatter stations in the North Atlantic that didn't see much difference between horizontal and vertical polarization. Similarly, it appears some commercial troposcatter systems communicate using both horizontal and vertical polarization as a form of diversity.
  2. Ground gain. Horizontal polarization gives you a few db (up to ~5dB) of ground gain over vertical polarization.
  3. Lower takeoff angle. I've seen some claims about this, but I'm not at all sure if this is the case.
  4. Better diffraction. Horizontal polarization may diffract better around obstacles like hills, mountains, etc. I don't know if this is analogous to how sunglasses are often vertically polarized because glare off of objects (e.g. water) tends to be horizontally polarized.
  5. Less QRM. Apparently interference (both natural as well as man-made) on some frequencies such as 2m is vertically polarized, so horizontal polarization avoids reception of it.
I was wondering if anyone who was familiar enough with the theory behind troposcatter/diffraction communications could key me in on how much better horizontal polarization is vs. vertical polarization and whether the info I've seen is correct.

Thanks,

Dan Fay KG5VBY in ABQ
Re: 6 mtrs, modes

Mike WB2FKO
 

FT8 was not designed to eliminate SSB on 6m, but to complement it. It's another tool in the arsenal and can be used when conditions don't support fast exchange SSB.  I operated for a couple hours this weekend and managed to make about a dozen FT8 QSOs when nothing was happening on 50.125.  Most of these QSOs involved inaudible signals (at least to my 59 year-old ears) with marginal conditions that are typical for this time of year.  Propagation was short-lived and erratic, but I never needed more than 90 seconds to get the needed information through.  45 seconds usually did the trick.  According to his QRZ page, I worked a guy in Ohio who was running low-power to an attic dipole.

If contest operators elect to use FT8 when propagation supports SSB, that's an unwise decision that will hurt their score.  I simply can't believe the contest community stops using SSB when 6m is wide-open as it usually is in June.  It makes no sense.

CW could be a different story.  My hunch is that FT8 or similar mode will eventually displace cw in marginal conditions.  It's more sensitive, far more reliable, and doesn't depend of the skill of the two operators which is sometimes incompatible.  When someone is CQ'ing at 30 wpm, I simply don't possess the ability to copy and reply.

Mike WB2FKO
Re: 6 mtrs, modes

Jonesy W3DHJ
 

On Sun, 20 May 2018, Keith Morehouse wrote:

Yep...I fear FT8 is going to kill contesting on 6M.
This June's VHF test will be very telling.

-W9RM
Yup... I'll be reviewing my experiences in the ARRL JUNE VHF and
the CQ WW VHF this Summer to see whether it's worth the effort
to continue my rover excursions.

Jonesy, W3DHJ
--
<pre> Marvin L Jones | W3DHJ | W3DHJ | https://W3DHJ.net/
Pueblo, Colorado | @ | Jonesy | __ linux FreeBSD
38.238N 104.547W | jonz.net | DM78rf | 73 SK
Re: 6 mtrs, modes

KC7QY
 

Bruce,

I just looked at DX Maps. There seems to be a pretty good Es opening in the midwest and lots of ops on SSB/CW. All is not lost to FT8. Still a LOT of FT8 activity as well though.

I caught a short SSB opening the other day and put 6 Qs in the log in about 5 minutes. Can't do that on FT8.
 
Jim KC7QY


From: Bruce Draper <bruceaa5b@...>
To: nmvhf@groups.io; nmbrc <nmbrc@groups.io>
Sent: Sunday, May 20, 2018 8:38 AM
Subject: [nmvhf] 6 mtrs, modes

I'm about to put my 6 meter antennas up again, and have been wondering if FT8 is still all the rage or if the digital frenzy might have cooled off since last Summer. I got my answer when I checked DX Maps this morning. One of the attached maps shows just CW and SSB spots, the other is just digital. Wow.

   73,
      Bruce AA5B
Re: 6 mtrs, modes

Keith Morehouse
 

Yep...I fear FT8 is going to kill contesting on 6M.  This June's VHF test will be very telling.

-W9RM

Keith J Morehouse
via Moto G


On Sun, May 20, 2018, 9:38 AM Bruce Draper <bruceaa5b@...> wrote:
I'm about to put my 6 meter antennas up again, and have been wondering if FT8 is still all the rage or if the digital frenzy might have cooled off since last Summer. I got my answer when I checked DX Maps this morning. One of the attached maps shows just CW and SSB spots, the other is just digital. Wow.

   73,
      Bruce AA5B
Re: 6 mtrs, modes

Steve Hutcherson <Wb5cts@...>
 

You are correct Bruce!  I’m designing a mobile/P system based around my new FT-891.  Glad your hoisting them backup and will look for you from DM33. I’ll let Pete WA7JTM, N7AMA, K7jE and the other guys know here in the valley.

73 Hutch
WB5CTS 
DM33VO 


On May 20, 2018, at 7:38 AM, Bruce Draper <bruceaa5b@...> wrote:

I'm about to put my 6 meter antennas up again, and have been wondering if FT8 is still all the rage or if the digital frenzy might have cooled off since last Summer. I got my answer when I checked DX Maps this morning. One of the attached maps shows just CW and SSB spots, the other is just digital. Wow.

   73,
      Bruce AA5B


<6mtr_cw_ssb.tiff>
<6mtr_digital.tiff>
6 mtrs, modes

Bruce Draper
 

I'm about to put my 6 meter antennas up again, and have been wondering if FT8 is still all the rage or if the digital frenzy might have cooled off since last Summer. I got my answer when I checked DX Maps this morning. One of the attached maps shows just CW and SSB spots, the other is just digital. Wow.

   73,
      Bruce AA5B
The Magic Band ( 50 mhz.)

pa3249@...
 

I got my email back, because I was not registered yet.

It's done now.


73'

Harry - PA3249



Van: Harry de Jong <PA3249@...>
Verzonden: zaterdag 5 mei 2018 20:54
Aan: wm0g@...; w7rap@...; n7mj@...; kx7yt@...; n7ur@...; af7pq@...; kb7hdx@...; ai7h@...; w5lhc@...; w5gm@...; ai6df@...; ve7beu@...; nmvhf@groups.io; kb5jlc@...; ag5s@...; shywyarc@...; arhill@...; ki7i@...; ve7ehp@...; langeler@...; ve5uf@...; c.leader@...; k7tnt@...; kl7ky@...
Onderwerp: The Magic Band ( 50 mhz.)
 

Hello 6 meter enthusiasts.


Would you be so kind to forward this email to 6 meter radio clubs and anyone who is interested.


I'm SWL since 1971 and began listening in 1988 on 6 meter. Till now I've heard 176 countries (175 confirmed - waiting for the JW7QIA QSL).

I prefer to listen to SSB or CW contacts, but the last years more and more stations using the digital modes, so I can not stay behind.

Last year (2017) the Sporadic E season was super. I know it's easier to hear a rare country or locator, than to make contact with.

For me the real DX with SP/E started half May and the first time with the JT65 mode, I decode many JA stations and VU - A4 - A7 - E44 - 3A (rare one for 

northern Europe, because of mountains in 3A) - 9K - UN7 - DS - YI - BD0 - XE2JS (DL68) - PJ4 - OX - EK7DX - BV - HL. Last good DX (outside Eur.) opening was July 30.

And of course all European countries. 

The reason that I write this is to let you all know - don't think, it's not possible for me because of mountains or whatever. I got e-mails from stations ( who were giving

CQ for a long time without making a contact) who were very surprised that I had decode them and some of them informed me that they have never made contact with Europe. I'm sure that KL7 and VE6 and 7 are possible via SP/ E.

One thing is for sure: you must be patient -  need luck - it's a good help when you know where the ES clouds are, so check the sites, like:  https://www.dxmaps.com/spots/mapg.php?&HF=N&ML=M&Frec=50&Map=EU  and / or   http://www.on4kst.com/chat/start.php   and of course the sites

in the USA and Canada. 

I hope to hear / decode this year again more new DX stations on the Magic band and remember, keep 50.110 free for rare DX stations.

I'm using a homemade converter in a JRC NRD 545 DSP and the antenna is a 5 elem. dual yagi for 4 and 6 mtr. I hope to install the next month my new ant. the 6 elem.

LFA Quad.

For all a good SP/ E season.  I'm checking 6 meter 24 / 7 during the season. 


All the very best,

Harry - PA3249   This is my page:    http://qrzcq.com/call/PA3249
Re: grid rarity

Bruce Draper
 

Thanks for the input, folks!

On Mon, Apr 30, 2018 at 5:59 PM, Arne N7KA <n7ka@...> wrote:

# of QSOs    FM28=1, FM29=24   That is out of 5696 6M QSOs.    Need FM14, FM25  and some decent propagation.

Arne N7KA
On April 30, 2018 at 3:44 PM Bruce Draper <bruceaa5b@...> wrote:

In your experience, which is more rare, FM28 or FM29?
Gotta be 28, right? Half of it is water, and the other half is very sparsely populated.
Re: grid rarity

Arne N7KA
 

# of QSOs    FM28=1, FM29=24   That is out of 5696 6M QSOs.    Need FM14, FM25  and some decent propagation.

Arne N7KA

On April 30, 2018 at 3:44 PM Bruce Draper <bruceaa5b@...> wrote:

In your experience, which is more rare, FM28 or FM29?
Gotta be 28, right? Half of it is water, and the other half is very sparsely populated.
Re: grid rarity

Keith Morehouse
 

I went back into the log since 2012, which is when I started operating from DM58.  Here's what I've worked on 6M, all double-hop of course.

FM29 - 21 QSO's
FM28 - 8 QSO's
FM27 - 5 QSO's, all with one station, N3MK
FM26 - 3 QSO's
FM25 - no QSO's

Next row west:

FM18, FM19 - > 20 QSO's per grid
FM17 - 14 QSO's
FM16 - 13 QSO's
FM15 - 1 QSO
FM14 - 3 QSO's
FM13 - none

-W9RM


Keith J Morehouse
Managing Partner
Calmesa Partners G.P.
Olathe, CO

On Mon, Apr 30, 2018 at 3:44 PM, Bruce Draper <bruceaa5b@...> wrote:
In your experience, which is more rare, FM28 or FM29?
Gotta be 28, right? Half of it is water, and the other half is very sparsely populated.
Re: grid rarity

KC7QY
 

Bruce,

I'll second (third or whatever)  FM28. I have FM29 confirmed from Socorro with just my 100wts and 3el.
 
Jim KC7QY


From: Bruce Draper <bruceaa5b@...>
To: nmvhf@groups.io
Sent: Monday, April 30, 2018 3:44 PM
Subject: [nmvhf] grid rarity

In your experience, which is more rare, FM28 or FM29?
Gotta be 28, right? Half of it is water, and the other half is very sparsely populated.
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