Other SOTA sites: SOTAwatch | SOTA Home | Database | Video | Photos | Shop | Mapping | FAQs | Facebook | Contact SOTA

VHF conditions


#1

My attempt to activate WB-019 today on 2m ssb was a dismal failure. Only managed to work 3 local stations despite calling regularly on 144.320 for half an hour. Odd thing was, that I could not copy the Angus beacon, which I can normally hear from May hill at S5.
On returning home, I checked the Angus beacon and it was still inaudible from the home qth. I can usually hear this beacon, at all times, under flat conditions.
I wonder if the ash cloud is attenuating VHF signals, or is the lack of aircraft trails (due to said ash cloud) creating a problem.
Any thoughts?
I did qualify the hill on 7MHz. Thanks to those who tried to hear me on VHF, and did not succeed. The walk was pleasant anyway and the pub great!
Perhaps I should add that I was using my usual system, 857 @ 50Watts into 4 ele Tona, which usually gets me round the country quite well
73, Frank


#2

In reply to G3RMD:

Hi, Frank.

Sorry to hear of your disappointment on 2m. It has always amazed me how consistent GB3ANG has been in the past despite the great distance - which is just as well with GB3VHF off air at present.

It was even audible on the FT-817 and 4ele from the five SE summits earlier this week if a little weak from Wilmington.

Maybe all that proagation is down to aircraft. Ken is always telling me now much traffic there normally is to the N of us.

I just tried looking on the Yahoo Microwave reflector to see it the lads are getting all excited - but I cancelled my subscription from my work e-mail address so I can’t :(.

73, Richard


#3

Hi Frank
I couldn’t hear you on 144Mhz, which was surprising and as you say the Angus beacon wasn’t there either or the Irish one !
You weren’t audible on 7Mhz either, but I did work John on 3.5Mhz though

Very strange, but you did qualify the hill and had a pleasant walk, so all is not lost as they say !

Hopefully work you from the next one

73 Graham G3OHC


#4

In reply to G3RMD:

Listened for you but nothing here. HF was poor too. I worked John GW4BVE but he kept dipping below an S7 noise floor on 80m. I had S9+ of noise on 40 & 60m at the time you were on 40 and only heard one station that came back to you. Noise level on 60m is now only S4, which is about normal here but I still have S6 on 40 and S7 on 80m although the rice crispies have disappeared.

73 Steve


#5

Hello Frank,
sorry to hear you struggled on 2m SSB from WB-019. As you know from the contacts we had–we had been in SW/ MW for the previous week working exclusively 2m though we did have to swap from FM to SSB and back in order to qualify the summits. Very quiet on 2m both SSB and FM at times.

Glad to hear you enjoyed the walk and also qualified the summit via HF.

Thanks for the contacts we shared over our previous weeks activations,

Best wishes, Gordon G0EWN and XYL Jenni. 73s


#6

In reply to G0EWN:
I was out /p today on a non sota summit and made 8 contacts no problem although some qsb with one station on the isle of Skye. The guy also mention of experiencig poor VHF conditions.

Seems the cloud maybe having an affect on radio comma indeed, any idea how long it is to last?

Adrian
2m0etr


#7

On the way home from Scotland yesterday afternoon it was really dismal on HF so I stopped off at Annandale and swapped the ATAS for the halo but heard the sum total of nada on 144MHz all the way home.

There seemed to be some kind of path across the Irish sea in the evening though: some of the Irish repeaters were up strong here in Cheshire (GB3NI and GB3LY inparticular). Same story with the WRB and NGI beacons, both up in signal as well but I didn’t notice any improvement in the Angus signal.

73, Chris


#8

In reply to M1DTJ:
Hi Chris,
Interesting. I can now hear the Angus Beacon again, but quite weak compared to usual. There are occasional meteor pings on it soI suspect it will stagger up to it’s usual strength over the next few days. There is severe qsb on it at present, which results in it disappearing into the noise. Very odd, I wonder what the increased attenuation can be attributed to.
73, Frank


#9

In reply to G3RMD:

My money is on lack of aircraft reflections. If I’m right, it will return to normal when air traffic returns to normal - a testable hypothesis!

73

Brian G8ADD


#10

In reply to G8ADD:

I’m with you here, Brian. It will, as you say be a testable hypothesis. Nothing here yet from GB3ANG. The difference from the 'RMD QTH which is only a few miles away is that mine is hidden below G/CE-003 to the north. Aircraft reflections would have a more pronounced benefit for me (radio-wise, that is).

73, Richard


#11

In reply to G4ERP:

GB3ANG was its usual strength (S5) on my 3 el SOTA-beam on Hegdon Hill, G/WB-023 at 1345 UTC this afternoon.

73,
Walt (G3NYY)


#12

In reply to G3NYY:

Still not a peep from GB3ANG either here or at Ken G3LVP’s or Stuart G0LGS’s.

73, Richard


#13

In reply to G4ERP:

I was up on Birdlip Ridge (IO81WT) at about 2 pm this afternoon. On 2m, GB3ANG was about S 2 to 3 on my 3 el SOTA-beam, which is an S-point or so down on its usual flat-band strength at that location.

I did think tropo conditions were extremely poor. I worked 2W0BTR/P on NW-032 and Geoff’s signal was much weaker than I would normally expect over that path.

73,
Walt (G3NYY)


#14

In reply to G4ERP:

ANG does seem down a bit at the moment. As a reference: when I switch over to the vertical it’s usually about s2 and well above the noise floor even during the flat, winter evenings but it’s barely detectable tonight. Aurora’s very quiet too so no fun tonight and it doesn’t bode too well for our little SOTA trip tomorrow.

73, Chris


#15

In reply to G3RMD:

The ash cloud is likely to produce a degree of attenuation. Satellite TV has been affected quite badly in some areas, although there is of course a huge difference in frequency.

There are some reports from the US that european HF stations have weakened since the eruption.

I had a look at the ash cloud map coverage and there is a gap across the Irish Sea, which co-incides with the observation of one poster.

Not a lot of evidence but what little there is suggests that there will be attenuation.

73,

James M0ZZO


#16

In reply to G3RMD:

Just to add my obs here, since the grounding of aircraft and the ash cloud I have experienced attenuation of all beacons here , gb3ang, EI2wrb , gb3ngi ,pi7cis , on0vhf are all normally audiable however Gb3ang is about the only one showing it’s head above the noise floor , to the point I have checked out my complete receive system masthead amp etc, all ok

Draw whatever conclusions… large stable high pressure/ ash / lack of aircraft…
fact is this is the lowest vhf propagation indicators I have seen at this location in the last 4 years, and coincidentally started at flights grounding…

waiting with interest on the ‘‘all clear’’

Ian


#17

In reply to G8ZVZ:
Hi Ian,
Thank you for your observations. The Angus beacon is still a lot weaker than normal at this qth. As you said, it will be interesting, but probably not very informative, when ‘normal service is resumed’ as flying will start when the ash disperses, giving two variables!
73, Frank


#18

In reply to G3RMD:
Hi Frank

Both GB3ANG & GB3NGI are now audible from here at typically usual strengths with some QSB
Could mean the ash cloud is thinning from the north ?

73
Graham G3OHC


#19

In reply to G3RMD:

Some countries are giving permission for low-level flights under the ash cloud which are being used to re-position aircraft. One country has given permission for flights above 36,000 feet, above the ash cloud. As the disruption continues it may well be that there will be more flights of this sort so that we may be able to judge the effect of aircraft whilst the ash layer is still there. Incidentally, one aircraft has flown through the cloud without damage, but I don’t suppose anybody will try to emulate this feat!

73

Brian G8ADD


#20

In reply to G3OHC:

In reply to G3RMD:
Hi Frank

Both GB3ANG & GB3NGI are now audible from here at typically usual
strengths with some QSB
Could mean the ash cloud is thinning from the north ?

73
Graham G3OHC

There is an embayment in the ash cloud to the west pinching out over Scotland but the drift seems likely to fill that in today.

73

Brian G8ADD