Aerials and VHF/UHF DXing

fatboymsport · 18-06-2009 01:15PM #1

a single 4.5m yagi is far from a monster on 2m i have one the same and i find it very poor i will be upgrading to a single 12el 8m boom in the next few weeks and hope to upgrade to 2 of them over the off season.

im still waiting to catch a 2m opening this year never seems to get to my location.

watty wrote: »

Nothing heard on 144MHz on my own monster aerial at 6pm to 7pm.

watty · 18-06-2009 02:30PM

It's only monster compared with a TV aerial

I agree it's not a monster by DX standards.

However Boom length of (2.5 x wavelength) is point of diminishing returns. The aerial I have is close to that in gain.

Theory and practical tests prove that a pair of 2.5 wavelength boom aerials phased gives near +3dB gain. A 5 wavelength boom only add about 1.5dB to 2dB gain.

Stack 4 x 2.5 wave long aerials (about 4.5m long for 144MHz) to get 6dB gain, that will outperform 2x 8m booms.

Also have mast preamp about 1m to 3m away from aerial array. Even with RG213 the RX loss is significant. I have the PA & preamp in a box just below the rotator.

Early mornings (after cold nights) bright sun with no wind is good. Even low lying fog helps Then you can get temperature inversion and very stable long paths. It fades as ground level air warms or a breeze stirs up the layers. All my best 2m DX is at breakfast time.

fatboymsport · 19-06-2009 04:33PM

are you saying that 2 x 4.5m boom 2m yagis stacked will have more gain than 2 x 8m boom yagi's ????

while i am no expert i can not see this being the case and you have not mentioned if the are stacked verticlaly or horzontal and at what stacking distance.

are you active on 2m ssb cant say i have ever seen your callsign spotted on the cluster ????

we are going off topic when i get time i will start a topic on vhf yagis and we can have a good old argument

watty · 19-06-2009 05:43PM

No.

That would be breaking laws of physics, or comparing rubbish 8m aerials

I'm saying 2 x 4.5m boom is sigificantly more gain than 1x 9m
and 4 x 4.5m boom is very much better than 2 x 9m.

There is almost no difference between 6.5m and 9m, maybe 1dB. Law of diminishing returns.

The stacking distance does trade off bandwidth, gain, polar pattern. There are several web site

experimenter · 19-06-2009 08:01PM

"All my best 2m DX is at breakfast time."

Alot of talk and little action

Glad I don't take you're advice when it comes to working 144MHz DX!

I get tired of hearing guys saying I got this antenna, this amp etc....but have no log to prove they have worked anything substantial on the bands...there a few EI's that have this attitude.

I have worked EA8 on 432 MHz single 19 ele yagi and 50w, 2735Kms, come back to me when you have done better with your monster.

PauloMN · 19-06-2009 08:46PM

experimenter wrote: »

"All my best 2m DX is at breakfast time."

Alot of talk and little action

Glad I don't take you're advice when it comes to working 144MHz DX!

I get tired of hearing guys saying I got this antenna, this amp etc....but have no log to prove they have worked anything substantial on the bands...there a few EI's that have this attitude.

I have worked EA8 on 432 MHz single 19 ele yagi and 50w, 2735Kms, come back to me when you have done better with your monster.

This sums up everything I dislike about amateur radio.

"My log is better than your log".

fatboymsport · 20-06-2009 08:18AM

there is a competitive side to every hobby, If you are happy screaming at itialians on the tripple 5 with echomics and rodgerbeeps on full tilt then fair play.

there is so many different aspect to amateur radio there really is something in it for everyone.

I have no great log on 2m i have not had a spardioc E opening this year and i am not qrv on 70cms.

location is a lot to do with VHF and if you dont have the location you need to make up for this with power and ALI in the Sky.

luck and being on the radio at the right time also help

watty · 20-06-2009 08:35AM

The only person Boasting is "experimenter".

My "monster" aerial is only monster compared with the car radio aerials. People doing Moonbounce have real Monster aerials.

Early morning IS often best for DX VHF, I've not worked much as I operate the Soldering Iron and CAE tools more than Microphone.

I'm not into collecting squares, countries, entities or doing contests.

Let's keep on Topic and not have sniping competitions. You can have a "what's wrong with Amateur Radio thread". (And I'd agree lots).

Radio has everything from Casual Scanner/SWL/Motorised Sat Dish to "Big Guns" Contesters, DXers and also Construction from AM "Crystal" sets to Microwave plumbing downconverting to FPGA based DSP.

fatboymsport · 20-06-2009 12:06PM

i have made one Eme (moonbounce) contact on my small yagi with a station in texas. i have recieved other stations from different parts of europe and Russia.

using digital modes makes EME a lot easier to do.

deaglan169 · 21-06-2009 01:20AM

got some great contacts today (saturday) on 2 ssb 100w and tri band vertical into portugal and spain im well chuffed with myself i caught the sporatic E by pure chance and bagged some new countries on 2, worth keeping an eye on tomorrow

les45 · 21-06-2009 08:48AM

My first 2 mt Station was a single 9 el Tonna with a Icom 202 and a very small
amplifier with 35 wats feeding the antenna . I worked all over EI and the west coat of G , from that antenna went to a 13 El Cushcraft and a slightly larger
amp , I gained maybe 100 k on a flat band , after a number of years on 2mts I finished with 4 Times 17 by M2 with a single 3 CX 800 A7 , with mgf 1302 Mast Head and LDF 750 , you could basically hear a flea fart in Ostend and I could work or I should say any other experimenter behind the key or microphone could work PA and ON under a flat band , so what !!!!!! . I worked nothing , the station and propagation did all the work .
You will work a hell of a lot with a single antenna in any spordic e opening or Auroa opening and during these openings the big guns like me will simply have no propogation and we just sit there drinking coffee wishing we lived somewhere else . So stick up the Tonna , get the best bit of Coax you can scrounge or buy, a clean Brick and a mast head preamp and keep a eye on the DX cluster and call CQ , sometimes you will be very very surprised at who comes back

De

EI9HW IO63MV

watty · 21-06-2009 06:35PM

1/2 of europe working through HB9HD Zurich Switzerland Sun Afternoon.

(29.690MHZ).

Austria, Italy etc open to Ireland on 10m.

experimenter · 22-06-2009 08:07AM

PauloMN wrote: »

This sums up everything I dislike about amateur radio.

"My log is better than your log".

Build a bridge and get over it....

I didn't kick if off, but someone needed to highlight the fact that you don't work DX on VHF/UHF at breakfast time....

As I mentioned, if you read properly, I dislike the fact that telling all that you have this and this gear, is totally irrelevant unless you have a log to back it up.

That's all...[FONT=&quot][/FONT]

watty · 22-06-2009 02:05PM

You can of course work VHF DX anytime.. But certain kinds of weather do favour early morning VHF/UHF DX. It depends on the mechanism. This is an established fact for DX caused by temperature inversion. Cold layer of air at bottom, hot layer on middle, cold layer above. Even at GHz you can get 1000km on occasion. As the ground warms the duct vanishes as the day proceeds. If you are on a very low or very high site you may never encounter this mode.

In UK a log isn't even mandatory. Not everyone is interested in a fat log book, though it's nice to have contacts.

Experimenter, you are off topic and unreasonable. Much of the point of this forum is not to boast about contacts (only you), but to discus techniques, equipment, aerials, frequencies.

experimenter · 22-06-2009 02:30PM

Thanks for the lesson in Tropo

I was wondering how I worked CT/EA8 on 144Mhz last winter.

I am all for discussing the technicals aspects of the hobby, it will not make you a better operator, that's for sure.

Since when did we starting discussing UK Logs, now you are off topic and unreasonable, A fat log does NIL for me, but to have a few exoctic contacts is nice.

I would like to clarify that you don't need a monster yagi and an early morning to work VHF/UHF DX. As the other poster mentioned, right time, right place, watching the tropo forecast charts will help predict band openings.

Good coax and a 9 ele tonna you can work some good tropo openings into UK and France and easily into central EU under sporadic Es conditions.

If you monitor the broadcast band, 88-108MHz for EU stations there's a good chance for 144MHz Es..

Good DX.

Spannerman14 · 25-06-2009 09:21AM

My car radio is tuned to BBC2 most of the time(88.70mhz), and during the good weather the station is blown out by Euro broadcasts which sometimes are as strong and clear as RTE... Radio Santa Maria even appeared on my RDS...:eek:

experimenter · 25-06-2009 09:32AM

I have seen that several times. This usually happens during sporadic E's which appear most summers.

As well as radio, it's also possible to receive TV DX from East EU and Spain..

humaxf1 · 01-07-2009 07:43PM

(I know different band, but) 27MHz was hopping last week. Had a quick contact into Croatia evening time with an Antron bolted onto the back steps...about 10ft off the ground. Usual French and Italian stations with their beams and toasters working full tilt lol.

watty · 01-07-2009 08:47PM

The Italians in the mountains are rumoured to use 10kW

Yes I worked Chicago with 50W and 18ft / 5.5m of wire (poor man's Antron) off corner of shack to side of house on 10m, that's a 1st for me, only ever had N.America on 80M before (3.8MHz and not often). Also Spain, even though blocked by the house entirely. (10m/28MHz). Half of Europe was working FM via the Zurich 29MHz repeater.

The only contact in last 4 weeks outside Ireland on 2m beam was Spain (30W SSB) at 9.35 am UTC.

watty · 02-07-2009 04:37PM

Play good, lads or it will get quieter about here.

Use Report Post Icon

and leave Modding up to Mods.

I'm not looking at anyone in particular yet.

experimenter · 05-07-2009 11:33AM

VHF DX..

Worked a dozen or so EA's (Spain) yesterday, 4th July on 144Mhz using Diamond X510 (Vertical) at 30 feet and 50Watts... could have worked more but was looking for EA8 (Canary Islands) on 70MHz!

les45 · 05-07-2009 08:36PM

experimenter wrote: »

VHF DX..

Worked a dozen or so EA's (Spain) yesterday, 4th July on 144Mhz using Diamond X510 (Vertical) at 30 feet and 50Watts... could have worked more but was looking for EA8 (Canary Islands) on 70MHz!

Any luck with the EA8

John

experimenter · 06-07-2009 07:50AM

CT3 was worked in GW on Friday, I was working at the time, so no access to radio..

Should be able to work EA8, as I hear CT quite a bit...

CT beacon is on 70.166MHz.

fatboymsport · 06-07-2009 10:50AM

are CT3 and EA8 going to be firsts when someone works Them ???

experimenter · 06-07-2009 10:54AM

I think so..

I have been heard in CT3 on 70MHz but no qso complete.

I am sure you could pick one up before the Es dissappear.

Aerials and VHF/UHF DXing

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