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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