Last weekend I had chance to try (for the first time in my short amateur radio career) some portable (or, at least “/a”) working. I was at my in-law’s farm in Bedfordshire and – in the heat of a glorious weekend that probably will turn out to be this year’s summer come early – I found myself a little table and settled down to see what could be had on the 40m band. It was hardly in the true spirit of /p operating, as I had only flat batteries in the FT817 and so decided to steal some mains electricity from the in-laws!
Those with 20/20 vision will notice that I’m still using my h/b straight key, rather than the paddle I built for /garden working to save the risk of dropping my Bencher. I haven’t worked up the paddle into a robust solution I’d be happy to take on a trip away from home (though I have enjoyed several qsos at home with it).
I was using the Walkabout Mk II antenna which I purchased from the Sandpiper stall at the Blackpool NARSA rally. I have to say, I’m amazed and delighted with that antenna – it really works well with the FT817, as Julian g4ilo concludes on his excellent site, where there’s lots of detail on this combination of Walkabout and FT817.
The walkabout antenna includes a jumper lead to short out the unwanted components of the base inductor. You can see the tapping sockets in the photo below…
I’m going to take this opportunity to record the suggested jumper positions (which came on a piece of A5 paper with the antenna which I’m in grave danger of losing). The table also shows the (approximate) length in inches of the telescopic section, which you need to adjust for best VSWR.
| Band | Connect 1 to : | Length |
|---|---|---|
| 80m | (N/C) | 48" |
| 40m | 2 | 48" |
| 30m | 2 | 18" |
| 20m | 3 | 48" |
| 17m | 3 | 30" |
| 15m | 4 | 48" |
| 12m | 4 | 37" |
| 10m | 5 | 48" |
| 6m | 6 | 40" |
| 4m | 6 | 22" |
You also need to use a counterpoise with the FT-817 / Walkabout combo – mine was a length of hook-up wire. Julian describes a neat idea of using a steel tape measure as an adjustable counterpoise. I guess I’ll give that a try next time I go to the hardware store!
All in all, the FT-817 and walkabout combo worked great mid afternoon on 40m – I had a nice ragchew with Henri, dl4vh, and several other qsos into Europe.
Try it – it is every bit as much fun as Juan’s video implied.
...-.- de m0xpd
Now that's what I call a garden!
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