I also have been able to try out the new SOTABeam 2m filter after a surprise visit from Santa Claus (the package wasn’t much bigger than a matchbox and I had no idea what was enclosed). On 29 December we were due to visit the Horseshoe Pass above Langollen GW/NW-042 and 43 so I knew I would be ble to try it out on the latter as Cyrn y Brain and the masts are notorious. I use a Yaesu VX7R handy, which is wide open to any interference that is around, with a dual band dipole about 2m above the ground and have had to use the M0JLA homebrew helical filter to hear anything at all on 2m fm.
The wind was blowing as usual so I hid behind the sheepfold and tried calling without the filter (explaining that i was not expecting to hear any replies) and heard nothing in reply or on any of the 145 frequencies. I then asked any listeners to QSY to 70cm and talk to me there. I received 7 immediate 70cm contacts with most of them telling me they had replied on 2m! Hence I screwed in the new little filter and tried again - magic!
As I trawled round the band the signal meter came alive and I could hear voices!! Nine 2m contacts were soon in the bag - along with another 3 at 70cm (Richard is right - it doesn’t work on 70cm… or rather it DOES but so efficiently that none of the signals get through!) and it was time to go down to the car and continue the drive to Snowdonia.
I was delighted and decided to keep the filter permanently in my kit so I didn’t get caught out anywhere else. My previous helical filter was a bit heavy and so only got carried when I needed it (and remembered). Thus on 10 January, back in my usual Welsh Borders haunts, we went up GW/WB-002, Brown Clee Hill and I looked for my usual spot down in the ramparts of this border fort where i got some protection from both the wind and the rather powerful masts perched on the top.
We managed a s2s with both Moel Famau and Moel y Gamelin (GW/NW044 and 042 respecitively) on the stick aerial before settling down but the trouble always increases when the dipole is attached. In went the filter and I started calling and got 16 replies on 2m (and 6 on 70cm) which sound very good BUT it was not easy as, I regret to say, I was still getting some interference from the masts (presumably) despite the filter. We would be chatting away and then suddenly the audio disappeared and returned some many seconds later. This happened increasingly often but It was sufficiently sporadic to just mean I had to ask people to repeat some comments but could complete all the contacts. However this was a disappointment after the fabulous results on the first hill. I hadn’t carried the helical filter up as well so couldn’t make any comparison. I do have to reiterate that the VX7R is reckoned to be one of the worst possible radios for dealing with interference.
After Brown Clee we went to the near neighbour Titterstone Clee Hill (G/WB-004)
where I sat as near the various masts as possible to check the filter again. Here I was mostly successful but was told that my signal was fluctuating at times. I was warned by G6NHW in Birmingham that my signal report was 57 until I inserted the filter when it went down to 43 but I was still receiving 59 reports from Telford and Newent but these are fairly close. I will have to investigate further and more reports will follow I’m sure! It is definitely a thumbs up from me and it will live in my kit – but possibly not quite perfect with my radio.
Viki M6BWA