Friday 13 August 2010


Flushed with the success of recent modifications to my straight key, attention turned to the m0xpd g5rv antenna.

The antenna has be "misbehaving" over the past few weeks - first symptom was a sudden change in the required settings on my MFJ-969 ATU, along with a sense that performance was poorer than in "the good old days". But things came to a head when the antenna suddenly started presented a changing load, such that I could tune for great VSWR one minute and the next, the indicated reflections were enormous. I had to do something!

After checking the feeder and all the cabling between rigs, switches and the ATU, I finally dropped the g5rv and had a look at the centre...

Sure enough, the left hand connection in the photo above was not only rusty - but LOOSE! I replaced the machine screw and nut and tightened up - and I'm pleased to say that the g5rv is back to its old ways!

I had a few more QSOs on 80 and 40m with the "trusty rusty" FT101ZD and then I decided to try something which has been on the "to do" list for a few months...

I fell for an old HW-7 at this year's Red Rose QRP Rally, but hadn't yet been able to try it in anger. I had discovered a few "idiosyncrasies" about the rig:

First, the jack socket for the key is isolated from ground (you can just see the fibre insulating washer in this photo)

I subsequently discovered that this strange arrangement is such that the rig can be used with the "Heathkit Electronic Keyer, Model HD-10". That's all very well - but it couldn't be used with my "Funky Keyer" until I made up an adaptor.

Second, the RIT control (part of the g4zqk suite of mods to which my example had been subjected) needed to be set a long way from the indicated "neutral" position to net anybody...

After I'd cracked these little "issues", the rig was ready to rumble...

I hooked her up to the newly rejuvenated g5rv and answered a CQ from fellow FISTS member Brian, m0brb. He gave the HW-7's 2 Watts a 559 in Devon. Thanks Brian.

The HW-7 works well enough, but I'll be using it more as "novelty" than as a serious rig. I is stable and generally easy to use - but I HATE the buzz-saw sidetone (regular readers will know I'm fussy about sidetone). It is good to own a nice piece of history and it certainly makes me feel "at home" when I leaf through old numbers of SPRAT!

...-.- de m0xpd

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