Testing the X-510 Collinear

Old Reflector
1

Beam or vertical for VHF? No doubt, the arguments will rage on forever. Last year, I took the X-510 onto GW/NW-43 Cyrn-y-Brain with mixed results, so I decided to give it another couple of outings on both G/SP-004 and G/WB-004.

My activation of Titterstone Clee on Friday was interesting, in as much as the VHF conditions were pretty much flat and activity on the 2m band was quieter than I would have expected (Olympics + holidays maybe). However, despite all this, the signal reports I was receiving were very impressive. Nearly all my reports were end stopping with the the six or seven Watts, I was running. An impressive contact of 135 miles was made with Paul GO4APL in Caterham and also a tricky 92 mile contact with a somewhat surprised Rob GO0HRT in Banks. OK, these would be routine contacts using a beam, however, to get them, I would have needed to work an awful lot harder and picking out Rob on the back of a beam would have been very difficult.

It was pretty much the same story from G/SP-004 on Saturday.

I’m still not convinced I’ve seen the best of this of this bad boy and I’m really looking forward to giving it a blast when VHF conditions are a little more favourable.

Just a couple of comments…

Is an X-510 practical for SOTA work?

Absolutely not. 2.5 Kilo’s of antenna and three swagged 5ft poles, making about five Kilo’s of your kit before anything else, not good news! A word of warning, this antenna at 33ft (including poles) is a real handful to erect in the wind and certainly not for the faint hearted. In fact, if I’m 100% truthful, anyone attempting to take this antenna on a SOTA activation, should reasonably expect to be sectioned :wink:

BTW, forget any ideas about saving weight by trying to mount this beast on a fibre glass pole, …one gust of wind and a fibre glass or even carbon pole will promptly disintegrate.

Does this antenna perform well? You bet it does, 3 x 5/8 on the 2m band will give some excellent gain and you can well expect to be sent a shed load of bills, for bent needles, as well as blown fairy lights, by the chasers.

There’s no denying, using a high gain collinear on a SOTA activation is about as much fun you can have at a couple of thousand feet ASL on the VHF band and something I’ll continue to enjoy. Sure, it’s time consuming putting the thing up and pulling it down and a real PITA to carry, however, when you look at your log book at the end of an activation and ask yourself ‘was it all worth the hassle’, the answer for me pesonally, is a no brainer.

BTW, I’d be interested in any of the Chasers/listeners comments after Friday and Saturdays activations?

Thanks to all the chasers this weekend, great to have you in the log.

73 Mike
2O0YYY

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In reply to 2E0YYY:
Hi Mike,
I’m not going to even try to convince you that heavy verticals are the wrong approach to SOTA, but I offer the following as food for thought.
I activated a couple of GI/MM summits on Friday on 2m and HF ssb. I used a pair of quad loops on 2m and a linked dipole for HF. These were supported by a mast consisting of my two walking poles (essential kit, now that I am over 70 years old). The walking poles are linked in a vertical configuration, by a couple of short aluminium connecting pieces. All of the antenna kit fits within my rucsac and total weight is under 1Kg. I worked the London sota regulars on 2m without any difficulty, as well as all of the regulars in the midlands. HF on 7MHz and 5MHz produced lots of contacts as well.
The approach to MM-8 and MM-9 is very boggy( above gaiters on occasions) and I suspect that I would still be immersed in it if I tried your approach to antenna systems.
I hope to do a couple more MM unique (to me) summits this week. I will alert.
73,
Frank

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In reply to 2E0YYY:

I contacted you on Friday on WB-004 at a distance of 51 km. The contact was a bit of a puzzle.

I have a 5-el horizontal yagi at 30 feet and a slightly lower 3-band vertical with a gain on 2 metres of 6.2 dB. You were S9 on the beam and S4 on the vertical. Bearing in mind a cross polarisation loss of a nominal 20 dB you should have been a lot stronger on the vertical than on the beam, but in fact it was the other way around. Either there was polarisation rotation on an obstructed path, or my vertical has a devil of a lot of unexplained loss!

I think that a small beam is a more sensible option for SOTA. Of course, you have to lower it and change its orientation to go from horizontal to vertical polarisation, and there is always the risk of losing contacts by not beaming in the right direction at the right time, but it can help to avoid overload problems when there is a strong station nearby and it is much more friendly to the mast and easier to put up and down. There is always the option of fitting it with 45-degree polarisation and accepting a 3-dB loss in both horizontal and vertical, still leaving you with a modest gain and no need to take it all down to change polarisations.

73

Brian GO8ADD

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In reply to 2E0YYY:
Hi Mike

I returned to Sharp Haw on Saturday (yes, remembered everything this time. Listened to you on the way up and gave you a few calls on my H/H from the top but you obviously couldn’t hear me. By the time I had got set up you had moved on but you were certainly a good signal.
Any idea when you are going to finish off the TW’s?

Dave/G4ASA

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In reply to 2E0YYY:

Beam or vertical for VHF? No doubt, the arguments will rage on
forever.

73 Mike
2O0YYY

Hi Mike,

Great to work you on WB-004 on Friday, and your signal was
very good indeed, although I believe you had reduced your power
by using a handheld when I worked you.

I suppose the comparison has to be between the X510 and a 5 ele
Yagi, as they both appear to have comparable gain. But of course
you’ve got to keep turning the beam, so although the X510 may be
a bit heavier, the convenience may make it all worthwhile.

It’s not me carrying it up the hill, though!!

Kind regards

Dave

6

In reply to 2E0YYY:

Beam or vertical for VHF? No doubt, the arguments will rage on
forever.

Only in your mind Mike; everyone else seems to have decided what works best for them on a case by case basis.

73

Richard
G3CWI

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In reply to G0ELJ:

A downside to a high gain vertical is that its main lobe in vertical cross-section is compressed close to the horizon, which means that the mast must be vertical. If you haven’t made sure that it is vertical or if the wind slants it then there will be segments of the horizon where the gain is reduced. I had mine on top of the beam originally, and the QSB as it rocked in the wind was very noticable!

73

Brian GO8ADD

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In reply to 2E0YYY:

Interesting stuff Mike. Are we taking this bad boy on Wednesday? If so, I wanna do a comparison with my floppy slim Jim. I want to see whether the difference in results is worth it. What do you think?

R

9

In reply to G7LAS:

Make sure you can get your antenna as high as Mike’s antenna or the comparison is not valid.

Andy
MM0FMF

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Tuesday nights are a good time to compare VHF aerials (and other aspects of your station) with peers. The population is much greater and therefore more data is generated.

Tom MO1EYP

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In reply to G7LAS:

In reply to 2E0YYY:

Interesting stuff Mike. Are we taking this bad boy on Wednesday? If
so, I wanna do a comparison with my floppy slim Jim. I want to see
whether the difference in results is worth it. What do you think?

No problem Rob.

So that’s a 22Ah SLAB, X-510 and 3 poles you’ll be carrying. Looks like a dead easy walk to the trig point for me ;-)))

73 Mike
2E0YYY

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In reply to G3RMD:

Hi Frank,

Thanks for all the info.

GL with your uniques in GM and I look forward to working you from your home QTH soon.

73
Mike

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In reply to 2E0YYY:

No problem Rob.

So that’s a 22Ah SLAB, X-510 and 3 poles you’ll be carrying. Looks
like a dead easy walk to the trig point for me ;-)))

73 Mike
2E0YYY

Yeah… I carried 22KG over 21 miles in Knoydart - I don’t think I’ll have a problem! :)))

Since then, carrying the normal radio gear seems less of a challenge!

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In reply to MM0FMF:

In reply to G7LAS:

Make sure you can get your antenna as high as Mike’s antenna or the
comparison is not valid.

Andy
MM0FMF

Don’t worry Andy… I’m taking an axe just in case :wink:

15

In reply to G7LAS:

Arf! Also, to be serious, have a listen to some of the 2m/70cms beacons on both antennas. The outputs from the beacons are a known quantity and they won’t get bored transmitting for you!

144453.0 GBB3ANG Dundee IO86MN
144469.0 GB3MCB St Austell IO70OJ
144482.0 GB3NGI Ballymena IO65VB
144407.0 GB3SSS Poldhu IO70IA
144430.0 GB3VHF Fairseat JO01EH

I think NGI and SSS may be off-air right now.

432980.0 GB3ANG Dundee IO86MN
432934.0 GB3BSL Bath IO81QJ
432970.0 GB3MCB St Austell IO70OJ

Brian G4ZRP tells me GB3ANG is audible at his QTH on The Wirral on an original FT-290 and a simple VHF “whitestick” colinear. 85-90% of the time over a difficult path. So you should be able to detect both it and GB3VHF.

Andy
MM0FMF

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In reply to MM0FMF:

In reply to G7LAS:

I think NGI and SSS may be off-air right now.

GB3NGI apparently returned to the air waves about two weeks ago - it is about S4 here right now (via a wormhole in the hills, cannot comprehend why I can hear it; GB3ANG is only 30 miles away and is never audible here except by aurora)

Barry GM4TOE

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In reply to GM4TOE:
Hi Barry.GB4ANG.Is always audiable here near Skipton N Yorks as is GB3NGI.But it is very rare that I hear GB3VHF or GB3MCB or GB3SSS. Yet if Don in Devon is beaming my way I can here him ok on 144 ssb.73 Geoff G6MZX

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In reply to G6MZX:

Bet you don’t have a 4000 foot hill directly in the way!
Anything in an arc South East to South West of here is unworkable from my qth at 1100 feet!

Barry GM4TOE

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hello mike,
from a chaser point of view.
i use a X510N on a 10’ pole in the back garden.
for me it is the best antenna for vhf fm i have ever used.
just my input.
73,
mark.

20

In reply to GM4TOE:
Hi Barry Fair comment.But I do have a lot of surrounding hills.But nothing like you have ATB Geoff