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HF with a 2.5m whip, from a town center, choice of band?

Ok so not quite SOTA, but I have permission to operate as a pedestrian mobile Special Event Station again this year, this time during the 12mile long Lions Mid-Summer Walk, between Doncaster town center and the town of Thorne, on the 26th June (SES callsign to be confirmed)

For HF the radio will be my PRC-320 and its 2.4m whip antenna. I’d like to try and maximise the number of inter-G contacts, which would normally suggest 40m, but also try and get the best balance with antenna efficiency.

What are peoples thoughts on band? Im still leaning towards 40m, and hoping the SES callsign and a bit of judicious advertising pulls in the QSOs, but am open to ideas!

Martin G7MRV

40 would probably be your best bet, especially if you’re trying to stay within your call area. Is you’re whip antenna loaded for 40?

The whip is a straight 2.4m rod (although sectional for stowing away). The radio itself contains a built in manual ATU designed for matching short antennas.

Forty has been pretty iffy lately, does that rig do sixty?

Brian

The critical frequency does not reach or exceed 7MHz on many days so 40m might not be successful - especially for /PM with a very short antenna. I would have a fallback plan.

Brian, it will go anywhere from 2 - 29.999MHz! The downside is that to do so involves either me taking the thing off my back, or getting Bob M1BBV to open up the pack, change band, change frequency and rematch the antenna for me. Even with the LiPo battery its a beast, but once thats used its back to the NiCds!

One thought though - im not sure SES are allowed on 60m! I can confirm that with Ofcom though.

Bob will be operating on 2m FM as we go, hopefully with some form of backpack mounted antenna and around 20W, depending if the programmer I need for the VX-2000 comes in time!

The walk is fully supported though - were just two of about 500 walkers on this! So we can swap bands at the rest stops and try something else if 40m isnt playing. The problem there is the delay after moving before people start to find you again! Unlike SOTA we cant spot that on the 'net!

Hi Martin,
I would have thought 2 metres would give you a more consistant coverage - not as far as 40m but more local coverage. I guess it depends what you are looking for - sounds to me like a 2m HT with a 1/4 wavelength whip would also be a lot lighter to carry.
If you particularly want to use HF/MF I guess the antenna will be horribly inefficent on 80m (and 40m as well) - in any case, you could spot yourself (or have someone spot you) on the DX Cluster - I’ve seen this done often for special event stations.

Ed.

Not sure about the SES issue - ISTR that it was not permitted on 60m but can’t put my hand on justification for that view atm - that would be a question for the RSGB. As would be whether /M operation of an SES is permitted. What is certain is that operation from other than a fixed location on 60m is not permitted. Suppose you could stop every now and then and call /P :wink:

73 de Paul G4MD

Operation of a SES mobile is generally not permitted. As far as I know, last years Lyke Wake Walk and this years Lions walk (both me and Bob) are the only times Ofcom have authorised such a thing. I think partly as I have a working relationship with spectrum planning, but mostly because I pleaded and begged and submitted huge volumes of maps and grid references, and am willing to adhere to some very stringent criteria! The main reason for SES to be fixed locations if so that ofcom can easily find and shut you down if necessary - so I have to provide routes, timings and locations to fine detail so that they know where and when I will be! In this case, there will be around 550 people who could direct the officer to us! :wink:

It is my understanding that SES are not allowed on 60m, but ive no clarification of it.

Sorry Martin, can you expand SES for me. To me it means State Emergency Services - which I guess is not what you are referring to.

… and adding /PM (for pedestrian mobile) to your callsign is going to cause all kinds of confusion :smiley:

Sorry DD5LP,

Special Event Station

In this particular case we dont have to indicate that were moving with a suffix, as the whole route is, for the purpose of the license, considered to be the station location. In the way that a normal special event is ‘fixed’ at a site, but the actual radios and antennas could be anywhere within that site, our site just has rather more space for us to be within!

I think we will work on a plan to switch bands at regular intervals, perhaps at each of the rest stops. If we start say, low in frequency and work up the bands, then it might be easier for people to find us.

And the idea of spotting on the DX cluster - i’d forgotten about that!