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After satisfying myself with regard to the operational integrity of my new 15m monoband EFHW on the Lunchtime Net last week, I thought it time to add some complexity into the mix and see if everything continued to hold together like it generally does at my home QTH.

As you can probably see from the photograph below, having taken the A272 east to the northern boundary of Chailey Memorial Common, the dog was pretty exhausted. The good news was that the mag-mount had kept the 10m whip in place on the roof magnificently.



Once there, I dispatched the wife around the common with said dog, while I set up the radio gear. Other than the End-Fed antenna (being sensible for a moment, it's a self-constructed plywood drive-on mount with Barenco tilt-base, custom 1m alloy support pole, 10m DX Commander Classic and a home-constructed 49:1 QRO impedance transformer) I'd chucked just about everything else I could think of in the boot with which to test its capabilities.

I started with my NanoVNA to check the antenna resonance in the field as opposed to on my driveway, and surprisingly it was quite different. Sadly the radiating element was too short, but not by that much. The analyser displayed a superb-looking dip at around 21.8MHz, and with reasonable bandwidth. Click the image below to enlarge.

I'll address this length anomaly later, but I'll be cutting an element for each band, so I'll just reuse this one for 12m.


NanoVNA Saver


Next up was my LDG IT100 Autotuner connected to the trusty Icom IC-706 MKIIG. I've only rarely used this tuner, as I have my preferred MFJ-949E manual tuner back in the shack. It's a great bit of kit though, and it's going to be given a good workout this summer whilst I'm out and about. It happily tuned my End-Fed on 17m and 20m, but I left it at that for today. Too much other stuff to get through, and I just wanted to make sure it still worked and was happy on the (spare) car battery.

Last week, I invested in a Huawei Category 4 LTE USB dongle so that I can have decent internet access in the field. I don't have a mobile phone for reasons I won't bore you with, so this was the best solution for me. Having pre-configured it at home, it worked perfectly in Chailey which was surprising seeing that Chailey has only recently been connected to mains electricity and sewerage.

An old Dell laptop was pressed back into service running Windows 7 with the usual WSJT-X suite as well as some other bits and bobs. With CAT control hardware & external sound card connected, I had to do the usual dance of the Windows USB-COM fairies and then make the requisite changes in WSJT-X before letting Dimension 4 re-synchronise my clock via the 4G dongle. I was then looking at a screenful of FT8. Way more FT8 signals than I usually see on 15m, so something was working.


First FT8 Portable


A very low noise floor in the car-park helped to offset the cacophony of shoutyness from the irritating contesters on the band. A few 100W full duty cycle transmissions later and a handful of QSO's in the mental logbook (no, I don't keep a proper log either - have I no shame?) as well as an impressive number and distribution pattern of signal reports registered on PSKreporter, I moved on to my final test of the afternoon.

The Icom packed safely away, I connected and fired up my fantastic SDRPlay RSPdx SDR receiver. With SDRUno running on the laptop, the full beauty of a slice of spectrum crammed with every type of amateur transmission was displayed. I simply love this software, and chuckle to myself every time I use it knowing that it looks a million dollars and costs as much as good manners. Click to enlarge. Do I have to keep saying that?

To be honest, I'll exploit any opportunity to post a screenshot of this software. Here, it's dealing with signals on the 40m band and beyond, albeit using my single 15m (6.7m physical) element.


SDRUno - The most beautiful Piece of Software Ever Created?


Anyhow, the objective of checking and testing interoperability of all the various tech I'd gathered together for the day (which shall forevermore be known as /p0 day) was complete, and it was time to head home for tea.

More tales from the trails soon. How will a 20m element work? Will I have to employ a little foldback/linear loading? Will a small loading coil bring the 10m resonance point down, like it does on a 40m EFHW setup? Is anybody reading this nonsense anyway?

Stay tuned.

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