The only remote antenna switches I know of that actually "work" at UHF are the Dow-Key/Transco types, which I've used with great success for many years. The "M" series products have 0.05dB attenuatio
[Steve Katz] Hi Steve. My work has nothing whatever to do with ham radio, I'm in the computer industry; however I've been a ham a long time and have a good memory, I guess! Dow-Key is very much in b
All kinds of stuff works on 160m, or on the HF bands in general. I just hope no "VHF-UHF'ers" are reading this and figure they can do the same thing... I've never been able to measure any attenuation
[Steve Katz] 9913 and variants of it only have about 2.7 dB/100' loss on 432 MHz. CATV hardline probably cuts that to about 2.0 dB, not a huge advantage. I probably wouldn't bother with the hardline
[Steve Katz] Yes, they do. The Transco M series have 100 dB isolation; I've actually measured it to be better than that, up through 432 MHz. It falls to about 100 dB at 1.2 GHz. It's a true coaxial
You probably wouldn't want to "pull back and swing up" very often. For an occasional operation, maybe. I'd prefer a multi-section very short tower (11') permanently affixed in the vertical position,
Sounds like old Rohn #6G tower to me. That preceded Rohn 25G and is not as strong because it lacks the webbing and has only horizontal cross-braces. It also has to be pretty old. Last #6 tower sectio
Mike, why can't you use the normal boom-to-mast bracket that the beam comes with, but use a tower leg for the "mast?" That's what I do... WB2WIK/6 "If everything seems under control, you're just not
Hi Bill et al... Of course, I've been there, and done that, too (small tower leg, large plate and U-bolts) but all I do is shim the tower leg with steel angle iron. That not only increases its "diame
[Steve Katz] Hi Pete. I agree I wouldn't use one leg of a Rohn 25G to support a 60' long 20m beam; but, then, I wouldn't use a 25G to support this on top with a thrust bearing, either. Common sense
[Steve Katz] As I posted twice yesterday, I use 2" angle iron (steel) shims, placed 180 degrees opposing each other, between the round tower leg and the boom-to-mast plate. This provides the correct
[Steve Katz] Hi Steve, I agree with you. That's why I posted yesterday I wouldn't consider a 60' monobander clamped to the leg of a 25G; although I have side-mounted a 36' monobander to a single leg
PVC tubing to stand off the line from the tower at the top, bottom and a few places in between seems to work. 12" spacing should be sufficient for 600 Ohm open-wire, a bit less should suffice for lad
Fred, what makes you think the problem is anything other than an aging drive belt? I'd simply replace the belt (a 5 min job, on the ground) and see if anything's wrong after that. -WB2WIK/6 "If every
[Steve Katz] The biggest problem there is that 9913 isn't very flexible, so one must be very careful during the "pull" process (getting the feedlines through the pipe) to assure the cable isn't bent
[Steve Katz] Hi Sherman! Two problems with the "overhead" approach (although the first one doesn't bother me at all): (1) Not recommended for lightning protection. If you get a strike, the energy wi
Hi Sherman, I've never had a problem with lightning, either, to tell you the truth. Here in the Los Angeles area, lightning is somewhere between "rare" and "nonexistent," so I don't even think about
There is a way to measure MOV degradation, for sure, but the device must be off-line. MOVs used doped grains of zinc (or other) oxide in series to build up breakdown voltage (since a single doped gra
Depending on how big that metal roof is, I'd be more concerned with losing antenna gain than with SWR...if the roof's big enough, it will become your "earth" and send a lot of signal up at a higher a
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