MFJ-1796 Go Live.
It's up.
It's not tuned, but it's up.
MFJ confirmed that the design now uses only 4 "medium" spokes per ring. OK. That didn't explain the issue of it being resonant around 7.4MHz on 40m when it should have been just below 7.0MHz.
I wound up calling MFJ this morning and Tom's only suggestion was to double check the number of turns on the coils. All is as it should be. Bugger.
I installed the new mount recently:
New "Bucket mast" complete with much more heavy duty wall anchors compared to the previous design. Needs a little more concrete yet.
I decided that I'd throw the new antenna up and see if anything changed at height, just to rule out the ColorBond fencing giving me grief.
I got it up without too much drama despite being a bit breezy. Putting the lower cap on when it was upright helped.
A quick scan with the SWR meter - things are about the same - that is 40m is bad. 20 and 15 are great and 10 isn't good.
A quick run over with the NanoVNA confirms what the SWR meter tells me:
I decided to go substantially lower just on the off chance the reading was far enough below that I might have been missing it and seeing some kind of unicorn level resonance for some other band. Seems not. It's there, and it's in the mid 7.300 MHz range.
So I guess if it's environmental, it's following me up.
Not at full height. I need to get about 1m more out of it, but on a breezy day in the sun and heat that's good enough for now.
The mast has a couple of holes in it 900mm apart. The plan is at some point to bolt through for full height. 2 person, no wind kinda job. Looking at it wobble, I probably wouldn't mind getting some guys on it through the centre.
With it up I hooked it up to the G90 and run its SWR sweep. Consistent with what everything else tells me. 40m sucks.
I kicked it over to 15m, turned the tuner off and it's effectively 1:1 on FT8. About where I want 15m anyway, so good for now.
I eventually jumped over to 40m and tuned around a bit to see what I could hear. Simply.. everything that the dipole was hearing. Some of it a bit cleaner (which could just be the 20 years worth of tech improvements over the IC706 which has the dipole connected). So far doesn't seem as blind.
Back on digital @ 15m and I managed to pull a couple of quick DXs - ZL and JA within a couple of minutes in the middle of the day, so I guess it works. And without the tuner on - something I've never really been able to do with the G90 before.
We're due for some wild weather shortly so I'm not sure how much playing I'll get done tonight. There's lightning in the area, though it may miss us. Either way, I guess it's going to give the mounting a fair old work out.
If MFJ come up with any more advice I'll need to bring it down and try to tune it some more. I wouldn't mind rotating it around a bit anyway.
The real interesting one will be what happens if I listen on 6m with the IC706. Very keen to see if I can hear anything - something I've never really been able to achieve before beyond a couple of locals TXing to a repeater that I couldn't hear.
In the mean time, I might as well just use it.
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