Sunday, 22 May 2016
May/June - Ilkley Moor
So the 144 UKAC at the start of May had dreadful weather - gale force wind and lashing rain. Putting the aerial up was fun, it's surprising how much pressure the wind puts on a 2 inch wide pole and the getting the pole into the clamp was rather scary!! The clamp keeps the antenna fixed but it's not nice jumping out of the car and getting soaked to change antenna direction. Still, the weather was no better elsewhere in the UK so the final result of third place was pleasing.
June's 144 UKAC was little better, the weather forecast was again very windy so I was prepared with ropes and pickets borrowed from G4ZAP stock. This time, I couldn't even get 2 x 12' poles vertical - without the aerial!! So had to drop back to 6' + 12' and ropes. For this leg, Erik turned up in 93AD and naturally won with almost twice the points of second placed G0EAK. I finished a reasonable 4th.
Then at the end of June was the second 70 UKAC and a chance to try out the new transverter feeding a 5ele Powabeam. I couldn't get on top of the hill so operation was from the side of the road:
The little white dot to the right of the mast clamp is the moon.
First time on 4m for years so this was a bit of a learning curve but 4th place was a good result.
July - out with G4ZAP/G0VHF doing VHFNFD at Walton on the Naze for the first weekend - radioed out for the UKAC!!
4 x 12 ele, top at 60'
Wednesday, 18 May 2016
A New Site - IO93BV
So with a fixed transverter, April was a big improvement (92 contacts/32 multipliers/472k points/4th place, but it was time to find a new location for the summer. I was also getting fed up with people asking me what I was doing in the pub car park.
The best hill with a road in West Yorkshire is Ilkley Moor and there’s a few places to park a car at the side of the road with a good take off for most of the UK.
The public road peaks at 380m but doesn’t go right to the
top and there is a significant obstruction roughly 20m higher blocking ENE to
ESE. There's a gated track to a higher area at 390m which was originally claimed
by police/fire services but their towers were removed a few years ago (thanks
to Airwave). A small comms station
remains and is still gated/fenced off.
By a stroke of luck, it turned out that I knew the ‘right man’ through
work and I was able to get access through the gate to the top. The access track ends north
of the existing building and mast so the site is slightly obstructed for a UKAC
contest - but great for Denmark and Germany!
The view to the south/southeast from Ilkley Moor. The boulders are supposed to prevent off-roaders churning up the ground.
Monday, 16 May 2016
Feb/March – building a 70MHz transverter
Back in the 1980s’ I was very active on
70MHz from home with a homebrew transverter (Jewell and Powis) feeding a single 4CX250 for legal
limit power. I had decided that since
144MHz UKAC was going nicely that I could fit in the four 70MHz contests, again
probably just in the AL section. So the
transverter was found (in the loft again) but I quickly realised it only had
0.5W output – enough to drive the ‘250 but not enough for the contest. Probably also a bit average on performance so I decided that a new transverter would
be a good thing to bring me up to state of the art. One quick email to G4DDK and a new unit was
in the post. Unfortunately, I didn’t
have enough time to get everything working before the 31st of March but I was
ready to go for June.
This is the G4DDK Anglian transverter in a 70MHz version with the 7W amplifier module on the rear panel. The box and cabling dates from 1985, just needed a quick re-wire of the DC, add some SMA plugs and away it went. For the record, 7W out with second and third harmonics >-66dBc - impressive. The front end is some modern device so no need to worry about the system noise figure and 24dB gain.
Jan, Feb, March
January – first time out and just about
everything went well until I jumped out of the car to turn the antenna and
walked straight into the horizontal pole on the roof-rack!! Fortunately the glasses survived although the
log sheets have blood stains. So first
lesson – try things out close to home so you can get rescued (or call an
ambulance) if necessary. I ended up with
50 contacts, 28 multipliers and 10th position – not a bad start.
February / March – icy, slippy and
cold. I’ve always owned cold weather kit
but make sure you are prepared. It’s
surprising how much cooler and windier it can be at the top of a hill so wear
layers and waterproofs and a good warm hat. Feb - 54 contacts, 26 multipliers, 7th place
March – After February’s contest I was unhappy tuning
speed of the IC706, you just can’t get up and down the band to search and
pounce. So I pulled the original HGT
system out of the loft: IC735 and a homebrew transverter. Side by side with the 706, receive
performance on a weak GB3VHF beacon was very similar and a good 10W output
available on transmit. However, for the
March contest, things were not quite right with horribly distorted locals being
received. I was able to get the transverter
onto some good test kit at work revealing an oscillating input amplifier. A quick re-build was required to calm down
the BF981. While sorting the preamp, I
also noticed a 5V regulator was getting very hot and this was being caused by a
20 year old tantalum capacitor failing short circuit. The regulator was preventing the tant from
getting enough energy to go bang and was still outputting 5V. Third lesson – check your kit properly at
home before going out portable!! March - 59/32/5th
Tuesday, 10 May 2016
Getting the antenna in the air
So 144MHz.
I wanted to keep things simple, I didn’t want to be taking afternoon
holidays to prepare so I decided to start with a simple set-up, taking part in
the AL section (10W, single aerial). So I got my IC706 from the loft and bought
a 9 element Powabeam yagi from the DX Shop.
Working out the mast took a little more thought but MM0CUG has a
drive-on aerial support that looked suitable although this is only ok for
small, lightweight aerials. I worked out
that a pole clamped horizontally to my car roof rack would be a solid second
anchor and also allow the beam to be rotated by hand and clamped tight. I had a couple of 12' poles available
(ZAP spares) so putting the beam at 24' was ok for one man to push up. My local friendly scaffold company were happy
to supply a couple of pole joiners and 90 degree clamps for cash. So a quick try out on the road outside my
house and all seemed ok.
MM0CUG mast support |
Mast gets clamped here, slacken clamp to rotate |
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