Well, sort of! Whilst connected to a standard SWR meter, or when using the rig's own internal SWR monitor, all was well in the world of the antenna match.
But, on connecting my trusty SARK-110 analyser to the antenna, I just couldn't get a stable reading. One minute it was showing a nice curve with low SWR, the next, it was showing a steady SWR of 5 or more. There was no such instability at the old-fashioned SWR meter or rig. The key to the problem was that the curve would often shown the hints of a good curve, but with horrendous noise spikes all over it.
This took me a while to sort out, because the strange MCX connector on the SARK never fills me (or some others) with confidence; I do wish it was something more robust-looking, even though it does seem quite well secured to the circuit board.
The problem got more and more unclear as days went by. One moment it would report a nice curve in the middle of the band and the next, some senseless curve that took off towards 26MHz.
Mightily cheesed-off this lunchtime, I disconnected the delta and connected an alternative feed line to it. This resulted in the SARK reporting an open circuit! I was certain both feed lines were perfect. This had to mean something to do with the SARK was at fault.
Eventually, with a multimeter, I checked the continuity of all the connectors and cable hitched-up to the analyser, to discover the real source of the problem: an intermittent break in the SMA patch lead supplied with the SARK-110. In case I had really lost track of what I was doing by now, I hooked the whole analyser system up to a dummy load and you can see the result below:
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| The impedance (red) going somewhere odd, whilst the SWR is up in the sky! |
A new patch lead is on its way from RS Components...
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