Page 2 of 2

Re: Potential backup 80m WAB Net frequency

PostPosted: Thu Jun 08, 2017 7:59 pm
by Graham G7LMF
As I'm newly returned to the hobby I don't have a lot to contribute to the conversation but for reference I know that Scouting use 3.740 as their net frequency.

Re: Potential backup 80m WAB Net frequency

PostPosted: Thu Jun 08, 2017 9:35 pm
by G4HPE
I raised the question about the viability of 3760 at the recent WAB AGM because it seems to be a topic which conversation returns to over and over again.
There are good arguments on both sides of the fence but the ones I have heard are:

PRO-3760
* It's deeply part of WAB history, as we approach our 50th anniversary. It appears in much literature, online and even on WEB SDRs.
* Many amateurs are familiar with where to find the 80m WAB net because the frequency is well published.
* WAB invests quite a lot in stationery which publicises 3760 as the 80m frequency. To move completely from 3760 would make our activity less easy to find.

ANTI-3760
* The Pip - said to be located in Rostov-na-Donu (Russia) near the Ukraine border and rumoured to be an AM marker signal for occasional national emergency flash alerts - is very strong after dark in the UK and makes weak mobiles or portables hard to hear. If you are monitoring for a while, such as a mobile station in transit, frankly it can drive you nuts. It now seems to be permanently on 3757 with wide-spreading tones that are difficult to filter out, and this has been the case since approximately 1986 when it moved from 5MHz.
* 3760 is in one of the 'contest preferred' segments of 80m. As such, for many weekends a year, WAB activity is virtually rendered impossible by high power stations with, all too often sadly, an uncompromising attitude to the activities of others.
* 3760 is the IARU Region 1 Centre of Activity for emergency comms. While we may not often encounter it, they are written into the bandplan and WAB is not.
* 3760 is dogged by very loud continental nets in what seems a particularly congested part of 80m. There is a group of intransigent French stations who come on to 3758 most evenings and have no regard for the activity that may be already established there or nearby. There is a strong German net on 3762 most days although they have been known to slide up the band if a WAB net is operating and our base stations are talking instead of just lurking.
* Mobiles with high-Q antennas can only roam so far from 3760 without a retune but in reality the chance of finding a clearish spot above 3760 is quite unlikely and, to avoid The Pip, tuning down the band you really have to go lower than 3750 where you also tend to encounter very congested frequencies.
* 3760 has been adopted by the Horizontal Net, who seem comfortable to curtail their early morning net if WAB activity is planned, but there is also anecdotal evidence that they have also shooed away WAB operators, even mobiles, if it suits them.
* 3760 is into the U1 band of domestic VDSL (high speed internet delivery over telephone wires) and the radiation can reach S9+ if you are unlucky enough to have neighbours who subscribe to this. There is an RSGB paper on the subject (I couldn't upload it because this forum does not permit PDF files, but I can send it to anyone interested).

The discussion at the AGM did recognise that 3760 is quite compromised these days and is no longer the nice clear spot it must have been when it was chosen all those years ago. But in proposing a change, there is a risk of jumping 'out of the frying pan into the fire'.

WHAT TO DO?

It was Jake G1YFF who came up with the suggestion of publishing a secondary frequency. Jake is a regular 80m mobile operator and has been annoyed by The Pip as much as any of us. But his operation from home is severely curtailed by immense VDSL broadband noise on 3760 and above.
A secondary frequency could be particularly beneficial after dark when the Pip is at its worst on 3760. The frequency of choice should be away from VDSL noise for the majority, although experiences vary. It should be outside the preferred contest segments, even though a significant proportion of contest operators do not respect the bandplan.
One issue might be that the secondary frequency is likely to be quite a few kHz from 3760, below 3700 for example. This may not be a problem for fixed stations but it may mean that to move from the primary to the secondary frequency will mean a significant retune of high-Q mobile whips, not always easy or safe by the roadside. But some mobileers may be willing to have two separate whips to fit, depending on the frequency in use.

The committee recommended a period of listening to see whether a better 80m frequency can be identified and this does seem like a good way to approach the problem. I have personally spent a bit of time trawling around 3660 kHz and comparing the general level of activity with 3760. It has been quite interesting but for me 3660 is very much less busy. Even if it is, a tune 3kHz to one side or the other usually finds an empty bit of band.

As was pointed out during the AGM discussion, the likely driving force behind any change would be the small band of regular 80m WAB mobiles. If as a group they felt strongly enough to take action and move, it's quite likely that this would bring about a new frequency otherwise a lot of squares would be missed out on!

For the WAB movement, perhaps the thing to be most worried about in respect of our current choice of 3760 is that a number of people, old regulars and newcomers alike, are struggling sufficiently with the various problems described to turn off prematurely and go and do something else instead. This cannot be good for the future.

As higher bands become unworkable inter-G, 40m we already see crumbling and 60m may go the same way, there is a measurable exodus of stations down onto 80m which is likely to get a lot busier as we bump across the bottom of the sunspot cycle. It would be good for WAB to have established a workable, recognised, regular, strong presence in one place on the 80m band - because 'possession is 9/10ths of the law'.

Re: Potential backup 80m WAB Net frequency

PostPosted: Thu Jun 08, 2017 10:04 pm
by m6kvj
hi all
as i said at the agm most mobiles can move up and down each way probably 15khz without retuning so that means, in my case i can operate anywere from 3.745 to 3.775 hope this helps
de 2e0kvj dave

Re: Potential backup 80m WAB Net frequency

PostPosted: Sat Jun 10, 2017 9:07 pm
by G4HDS
I think tonights test run on 3.660 Has added weight to Steve's argument.
I've been able as have many more chaps, to maintain constant contact with Steve as he drove square to square.
Only the rude arrival of an Italian contest station spoilt the fun for me.

It might be interesting to repeat the exercise, without any BLo**y Contests :x

73 Paul

Re: Potential backup 80m WAB Net frequency

PostPosted: Thu Jun 15, 2017 9:16 am
by G7afm
Any further suggestions on the preferred secondary frequency surprised at the amount of traffic & general noise on or near 3.660 mine is about the same level as 3.760 ,Now before anyone starts shouting that is a good frequency for me as it,s very quite then you will be the station to run the net if it ever get,s going,don,t expect a station with a higher noise level to take control so before a particular frequency is decided on bear this in mind.