Total posts : 45366
BC Man,,, I think I know what your problem is. Here’s an experience I had forty years ago:
I had just moved, after my field engineering assignment had changed, and I wanted to get my 100 watt ham rig on the air in a hurry in the 75 Meter (3.8-4.0 MHz) band. So I attached the far end of the “hot” half of my 135 foot dipole antenna to a power pole and laid on the ground the center of the antenna and the coiled up “cold” end. (The hot end was that leg attached to the center conductor of the coax cable and the cold end was that leg attached to the cable’s shield. I had something — I forget what — keeping the center insulator off the grass.)
I then tuned the transmitter, which had pi network tuning, like I believe the Hamilton has and the SSTRAN transmitter definitely has. I got good tuning but I wasn’t “getting out.” Hmm… So I took an old antenna current meter I had left over from my marine days (and the original 2-3 MHz marine band days) and stuck it between the cable’s center and the hot leg. (Ammeters become more and more useless as the frequency increases, but…)
I got good current. Another hmm… So I disconnected the hot leg — and the tuning and antenna current changed very little. I was tuning to the ground, tuning THE ground, probably capacity coupling through that coiled cold leg. So…
I think you are tuning mostly to that meandering “ground” wire you have. I’d be willing to stake my rep, such as it is, that if you removed that whip from the top of the transmitter, you’d see very little change in the tuning — or the range.
Therefore, I highly recommend what I posted last time — put your transmitter on a mast that reaches all the way to the ground and connect the bottom of the mast to a ground rod. Again, see the info at my web site. I just by instinct (gained from experience) plan to do what I posted at my web site. It’s called good engineering practice.
Antenna theory has more math involved than any other aspect of radio engineering, probably because antenna practice involves a lot of art along with science.
Speaking of good engineering practice… Re the way you have mounted the transmitter on the mast. Is that what Hamilton recommends? You have a “flag” there, and it will flutter in the wind, affecting the tuning and the integrity of the mounting. I can see the U-bolts loosening, allowing the transmitter to act as a weather vane and eventually slide down the mast — if the cables don’t wrap around the mast first from a rotating transmitter.
Another thing… Without a direct connection to ground, that whip antenna will be more of a lightning “magnet” than a drain to ground for static buildup.
Also, when using tie wraps outdoors, use black ones. The sun’s UV rays cause rapid deterioration of white ones.
I hate to be so critical, but I became a super tech and made a good living in the communication, navigation, and computer fields correcting problems created by degreed engineers with their slide rules and, later, calculators. Most of my work was not in labs but in the field, where reality sets in.
My biggest expose was proving that an expensive device that was supposed to allow seven transmitters tune to three antennas (on a Navy guided missile cruiser) didn’t work well. That multicoupler was designed and built by the famed Naval Electronics Labs in San Diego, CA.
By the way… I’m hoping my pipe mast-mounted SSTRAN will allow me to get usable range initially, until I can set up a base (coil) loaded (complete with capacity “hat”) antenna in the yard, which I know I’ll have to do eventually.
Bill in SE Texas