So its been another lovely sunny day down here in the QTH, but with a full day of work means a few hours in the morning and a couple in the evening to get things sorted.
Having done my analysis yesterday, I set about checking the mast. Whilst long winded, I had to be pragmatic and methodical in my approach to ensure progress was made.
- take mast down
- remove all wires
- measure wire outside with long tape measure
- compare to instructions, correct as required
- mount and test
- repeat for each wire
So having yesterdays results I took the mast down, which wasn’t too bad on my own given the mast is so light and guyed relatively low (well compared to the 2m/70cm mast which requires steps just to start! I disconnected all the wires, which was quite quick, then set about measuring the 30m wire.
With the accuracy of laying flat outside there was some 40cm of wire missing, so i cut some, re-soldered back on and reconnected, then re-erected the mast and radials.
I returned inside for testing with the NanoNVA – SWR still 5.5 – agggh ! What had I done wrong ?! so i went to check the basics, like connections,etc. All good there. I then tested the NanoNVA against the 2m antenna, SWR is fine. Then i though, could the other mast effect the DX Commander, surely not, but to make sure kept flipping the tester between antennas.. then it ‘hit’ me.. maybe i should recalibrate the NanoNVA for 30M. I set about doing that then…
Huzzah ! So, it maybe that I need to recalbirate for each frequency, or may not, anyway, to rule that out going forward thats what I’m going to do so the step plan becomes.
- take mast down (leaving known good wire on)
- measure removed wire, make corrections as required (lengthen/shorten)
- re-measure wire to confirm length
- attach to mast and erect
- test previous frequency is still working on the correctly
- re-calibrate NanoVNA for new frequency
Hopefully I will get the 40, 30 and17 completed today now i have a method, but another busy day of work is about to begin !