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Gw/nw-043 qrm

Sorry to the chasers that were trying contact me today on GW/NW-043 Cyrn y Brain.
I was having a problem that when my squelch opened on a returning call all I could hear was QRM so only managed to log 2 QSO’s. I could here people trying call me but the QRM was wiping them out. I am assuming that my Yeasu V8X-DE with my Sotabeams MFD doesn’t like the tranmitter towers up there.
Thanks to Stephen MW0ISC who did spot me and made the log.

Paul
MW0PDV

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The QRM is relatively new up there and it is also more of a problem on some radios than others. The VX8 is a brilliant radio with loads of features but is one that does suffer badly from on site QRM on 2m.

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I was one of those trying to call you Paul! I had similar issues last time up there. It’s no so bad on HF. Like Andy says, it’s pretty recent; it used to be no problem at all to operate with a handie from there. You may have been better walking across to the trig point - it’s in the AZ and (I think) just 1m lower than the true summit.

Conversely, Billinge Hill G/SP-017 where I was yesterday, and used to be a nightmare, seems much less of a problem these days. There is still some mush there, but it’s now relatively easy to activate from there with a VHF HT.

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I had a similar problem the first time I tried to activate this summit, on my second attempt I walked past both transmitters for approx 1/2km to the Trig point & Sir Watkins Tower remains. This location is well within the activation zone and is far enough away to reduce any impact from the transmitters. I used a handheld with a homebrew vertical dipole with success. I also activated this summit yesterday from the trig point using an Icom IC-2200 with my homebrew dipole, plenty of contacts with minimal breakthrough/desensing from the transmitters.

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The VX8 was Christmas present so only 2nd of 3rd time out. I do like the display but the first time haven’t taken the FT-270 with me as back up.
Lesson learnt :slight_smile:

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The VX series of radios have quite wide band front ends. This is so they can Rx on all the nice “features” like WBFM broadcast etc.

You may find that building a small band pass filter for 2m helps alleviate the problem. Some thing like

http://www.m0skm.com/index.php/2m-band-pass-filter-another

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I had a problem on Corndon the other day using a Wouxun handie which had behaved well before. No interference noticeable, but heavily desensitised.

Returning to nearby Stiperstones a few days later, I tuned around on my FT817 and found several end-stopping carriers, and a couple of data transmissions between 140MHz and 144MHz. I assume that these emanate from the commercial radio site on Long Mountain a few kilometres away.

The FT817 coped perfectly well on both summits.

As you say, Paul, its always good to have an alternative radio with you!

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Thanks for the link, interesting stuff there.

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I assume you were using a rubber duck. Dave MW0XRT was 5/9+60dB to me yesterday with his homebrew dipole. MW0ISC.

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No I was using a dipole, but had rode down the track towards Watkin tower and used the fence as a support. Turned out to be not the best spot as when the mist c!eared a bit it seems that I had found a bit of a hollow

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I had a similar issue on Callow Hill (G/WB-015) last week. I was up there doing some drone work, but took the FT-60 (well it would be rude not to…) only to be confronted with sounded like the noise of a Chinook at s9 on 2m. Only had the stock antenna, unfortunately.
Briefly contacted by a station around Gloucester, and Rod, M0JLA, but was unable to complete either QSO, so a complete failure. First time for one on callow Hill :frowning:

Don
m0hcu

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You weren’t using a large twin rotor drone, by any chance…? :wink:

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Not this time :grinning: Although there had been a few about. They had all disappeared by the time I’d packed up and decided to play radio.

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This summit has regularly been a problem on VHF over the years. I took a Baofeng handy with me last time and it was hopeless, couldn’t hear the multitude of people calling me at all. My Kenwood TH-F7E usually works OK though, much better radio. Try switching on the attenuator on your radio next time, see if it helps.

73
Roger MW0IDX

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Not surprised to hear of your problems on Cyrn y Brain, I gave up trying to make contacts up there on 2m with my Yaesu VX7R (with or without dipole) because of the interference. My solution was to tell chasers I was going to QSY to 70cm and then complete the activation there. The last time I went up there I erected the dipole, used a helical coil filter (made by M0JLA) and qualified the summit with no problem on 2m (but with lower power as the filter knocks it down a bit).

Surprised to hear of the problems on Stiperstones but haven’t been recently. I have had great difficulties qualifying Callow Hill on 2m FM but just assumed no-one could hear me and had to keep on calling until enough contacts were logged. Of course, if you time it right and ask permission, then you can improve the take-off by operating from Flounders Folly (the tower on top) and I got a contact from Cannock very quickly but didn’t have time to investigate further.

73 Viki M6BWA

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Activated Cyrn Y Brain in May 2017 without any problems using my Yaesu FT270 and dipole so maybe something has changed up there…?

http://gw4vpx.blogspot.co.uk/2017/06/gwnw-043-gwnw-042.html

Allan GW4VPX

As Andy said at start this thread its seems to be radio specific, I have used my FT270 up there with no problems. I had heard of people having problems and wondered what the fuss was about until I used my new VX8 :slight_smile:

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This will help massively and looks to be the easiest to make.

http://www.n5dux.com/ham/files/pdf/Build%20a%202m%20Intermod%20Notch%20Trap.pdf

Took the blunderbuss approach when I did it back in 2011, Allan :wink:

Using the FT-857, I knocked off 80 contacts, all 2m.

64 on fm and 16 ssb, all made on an X-510 colinear.

73 Mike

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