Saturday 9 October 2021



Trying to get my 40-10M EFHW to work on 17M is like trying to fit a square peg into a round hole. Sure, with the right  ATU I can force a match, but it's not ideal.

I purchased the bazooka direct from the manufacturer - a small company called Wire Antennas - the same place I got my EFHW from. When it arrived, I was a little surprised to find that the case-lid had quite a few scratches on it. Other than that though, everything else looked of high quality and a replacement lid was posted to me as soon as I notified WA about the problem.

When I opened up the box to fit the new lid, I thought the treatment of the coax-braid was a little "scraggy" but despite its appearance, it seemed solid enough. Bear in mind that this thing is only 30-odd quid, so it's not fair to tear it apart. 

In the small garden at the back of my bungalow, I have an EndFed HalfWave (also from Wireless Antennas) and a half-size G5RV. I was going to take down the G5RV and put this Double Bazooka in its place, but in the end I decided to give myself an easy weekend by doing a trial-install in the attic instead.

The antenna is only around 26ft long, so it makes for an easy installation in most spaces. In a flat-top dipole configuration, you only have to find 13ft of space for each leg and if you put it in an inverted-vee, you need even less space!

This 1950's design antenna is 98% efficient and it's extremely broad banded, meaning that the VSWR remains pretty constant throughout the 17M band - typically less than 2:1 so no antenna tuner is required whether you work in the CW or the SSB portion. When the antenna arrives, the two looped ends are left loose so that you can erect it and make small adjustments to the length to get the VSWR perfect for the part of the band that you use the most. Once you're finished tuning it, simply tighten up the two clamps and away you go.

Connecting my NanoVNA-F analyser to the antenna revealed that I needed to make some adjustments to focus it on the top end of the band which is where I work almost exclusively. As advertised, the VSWR was under 2:1.

Back in the Shack, I connected the Bazooka to my trusty ICOM IC-705 and was slightly disappointed with the noise level but this is no doubt due to the location of the antenna rather than the antenna itself. Looks like I'll have to make the effort to put it outside after all.

Anyway, I tuned around and found some activity. It wasn't long before I was breaking in to QSOs. Signal reports weren't very good, but again, that's because of the loft location. 

So it's going to be needing another look-at when I get around to putting it outside. I'll update this post then.

73, Tom, M7MCQ.

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