SS is a terrible conductor. If you need high strength, copperweld would be much better. Beware of stranded copperweld: The abrasion between strands can erode the copper and expose the steel. 73, Scot
Of course, that would require twice as much lifeline and one very large (5/8", 6,000 pound) pulley. Because my tower is 70 feet, and the lifeline comes in 100 foot increments, I would have had to buy
Anyone who has ever tried to manage solid number 12 copperweld can appreciate the advantages of stranded. Even solid 14 and 16 are hard to handle. However, as noted, stranded copperweld doesn't last
I have some 300 Ohm window line that's been flapping in the breeze for about 30 years without breaking. I think it's copperweld. What I did do is build a good strain relief for the connection to the
I had an original Cushcraft A3S, which had trap coils and screws coated with the hard epoxy. The screws clearly weren't going to turn, and I never saw any evidence of poor connections, but I suppose
I once had a 2 element small receiving loop array with my 70 foot tower in between them. I knew that re-radiation from the tower would be an issue. The tower was shunt fed on 80 and 160. I was able t
It's a multiple of a half wave on all those bands, which means the feedpoint impedance is very high, typically 2,000 to 5,000 Ohms. A good transformer with a turns ratio of about 8:1 should get it wi
"all"? If it were about 65 feet long, it could be a half wave on 40 CW, and a full wave on 20 low phone, 1.5 wl on 15 high phone and 2 wavelengths on 10 FM. (The resonant frequency increases by a fac
I haven't tried it, but you could do a simple model experiment. Model a dipole with various different swaged sections: ignored, average diameter, etc. Use lots of segments, and see how much the reson
I went through a similar exercise with a 40 m EFHW for 40 and 20. It is true that the full wave resonance is not exactly twice the full wave one. I designed and built a small QRP tuner specifically
A somewhat more general question: There is a whole bunch of trapless tribanders available now, all based on modeling. How well do the predictions of NEC4 models for these antennas really agree with a
Yes, base up or base down. 73, Scott K9MA -- Scott Ellington -- via iPad _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTa
I can confirm that. I had a PRO-67B years ago. After putting it up twice due to defective traps, I took it down and returned it to Mosely. The only band on which it worked was 17. 73, Scott K9MA -- S
I'll add my own experience, for what it's worth. My tower is 67 feet of Rohn 25, originally with a D40 rotatable dipole at 75 feet, a TH7 at 70 feet, and an A3 on a side mount at about 50 feet. The o
I recently tested some of my retired 30 year old RG8 and 9913. None had water damage. Loss was very close to the spec, maybe just a tiny bit higher. Most of it was exposed. I reused some of it for 80
I bought a rebuilt T2X from W7KD last year. It was in great shape. I think he also does repairs. You might also check with N4TB. 73, Scott K9MA Has anyone sent theirs to MFJ for a refurbish? I got on
Charlie, Are you sure it is not the tower itself that is degrading the performance of the 4-square? If so, you may be able to detune the tower with a gamma match. That worked on 160 for me with a 70
The interactions, based on my modeling, usually affects the nulls in the pattern much more than the forward gain. This is mainly a concern for receiving. 73, Scott K9MA John KK9A I have an 80M wire 4
Probably one or the other, not both. That's "overconstrained", which means anything just slightly out of true can produce very large forces. The easiest way is usually to let the rotator take the ver
The thrust bearing reduces the bending moment on the rotator, not the mast. With the rotator in the tower below the thrust bearing, there is very little bending moment on the rotator, just a horizont