As a relative newcomer to the hobby of amateur radio, I have been experimenting with different types of antenna to see how best to make use of my legally permitted 10 Watts (I'm a UK Foundation License holder), whilst keeping good relations with the neighbours and the local planning department.
My QTH is a listed building in the middle of a conservation area, so there's no question of a mast going up in my garden. On the plus side, I live right by the beach, just above sea-level, so have good ground below me.
For most of 2009, the deep solar minimum, and resultant poor HF conditions, ensured that most of my radio time was spent on the amateur satellites, with only the occasional foray on 20 metres (via an indoor, resonant, dipole, +/- 9m above ground, up in the attic), or, less frequently, on 15 and 40 metres (by way of a half-size G5RV, also up in the attic).
I wanted to mount a multi-band vertical antenna up on the chimney stack, which would give decent HF coverage with minimum visual impact. I considered the Comet CHA250B, Diamond BB7V and Moonraker GP2500 amongst others, before deciding on the SRC X80. A big part of the decision was based on cost. I didn't want to spend over £300 to buy and erect an antenna, only to be told by the local authorities to take it back down again. The £45 price tag on the X80 made it the obvious choice.
The order was submitted and two days later my new antenna arrived.
A quick inspection confirmed that all parts were present and correct, and I set about laying it all out on the driveway before beginning the assembly.
The radiating element of this antenna consists of six, progressively smaller diameter, aluminium tubes, inserted into one another (telescope style) and held together by jubilee clips. The instructions say to insert each section 6cm into the next, leaving the antenna 21 feet long.
Snowdonia's website, as well as the instructions, state that this antenna is 5.8 meters, or 21 feet long - but 5.8 meters is actually only 19 feet! I wanted to assemble this antenna correctly and needed to know how long to make it, so I gave Snowdonia a call.
Simon at Snowdonia came across as enthusiastic, knowledgeable and keen to help. He explained to me that the antenna was designed to be 5.8 meters long, but some people had been experimenting with them and making them longer. From a health and safety perspective he was forced to include the instruction to telescope at least 6cm per section (any less of an overlap wouldn't be safe).
For my situation (wanting to keep the antenna as stealthy as possible) and my QTH (exposed sea-side location) this was good news. Shorter meant that not only would it be less visible, but with more of an overlap in each joint, the antenna would better resist the high winds we regularly experience in the north east of Scotland.
With the antenna assembled, I Denso-taped the top of the antenna, each joint, the unun and the coaxial connection (this is not in the instructions, but my locality to the sea makes this almost a necessity).
Less than an hour from opening the box, my new antenna was up on the chimney stack (fixed with the base around 10 meters above ground), with 25 meters of low-loss coax joining it to my Icom IC-736.
The antenna tuned-up quickly and easily on all bands 10 - 80 meters, and also, surprisingly, on 160 meters too (I tried 6 meters as well, but no chance!). A quick (and, admittedly, unfair) comparison between the X80 and my 20m dipole showed the vertical to be noisier (by 1 or 2 points on the S-meter) and to be 1 or 2 S-points down on received signal strength. Static noise can be reduced by earthing the base cradle, but I didn't want to run another wire down from the roof (yet!). The X80 is very flexible (think 6 meter long fly-fishing rod) and the signal can come and go as it moves in the wind.
Unfortunately, I had very few opportunities to play radio over the next few weeks, and whenever I did, it was on 20 meters, where my preference was to use the dipole (as a relatively new ham, virtually every contact is a "new one" for me, and I wanted to give myself the best chance at making them).
The end of 2009 and beginning of 2010 saw some decent solar activity, and with it came some openings on 17, 15 and 10 meters.
My first contact with the X80 was made on 17 meters SSB, and was with Fred, K8CW. I heard him calling CQ, gave one shout and he came back straight away with my callsign. My signal was only 55, so the QSO was a bit strained at times - but I had just made a contact in Ohio from Scotland (a distance of 5700km) using a multi-band vertical, and 10 watts, during the deepest solar minimum for half a century! To put this in perspective, my previous farthest contact had been with RZ3TZZ, a Russian club in Nizhny Novgorod, 2800km from home.
I have since made contacts using the X80 on 40, 20, 15 and 10 meters, including my first IOTA QSO (2M0OSK - Andy on the Isle of Harris), and my first short-skip QSO (with M3GFQ - Lenny in England). The X80 consistently out-performs my G5RV junior, often achieving a contact when the G5RV doesn't even hear the other station.
The X80 has withstood some awful weather over the last few months, with winds reaching around 50mph at times (not extreme, I'll admit, but I'm sure we'll get 60mph+ before the winter's out). I've been outside watching how it moves in the wind, and after seeing how much it flexes, still find it hard to believe that it returns to stand straight when the wind dies down - testament to the strength and quality of the aluminium.
So, in conclusion, what can I say about the X80? Will it out-perform a resonant dipole (or a Yagi or a cubical quad)? No. Of course not. But if you need an unobtrusive, multi-band, vertical antenna, for a very reasonable price, I would suggest you look no further than the Snowdonia website.
I intend to post updates on this antenna (performance improvement or degradation, physical condition etc.) as time goes by.
Until then, best 73's, and good DX. MM6FSP.
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