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Twin X-Mount Dipole Idea

Doing a quick search on the Maco website I see their 3 element beam on a 11.5 foot boom has 3.99 square feet of wind load. The CP version on a longer boom with another set of crossed elements would have noticeably more wind load, placing it outside of this rotors specs. If the rotor is mounted inside the top section of a tower, you may be able to use it without issues.

Update: I now see the M-103HV with both vertical and horizontal elements comes in at 6.2 square feet. Considerably more than the rotor is rated for. This might not even pass if the rotor is mounted in the tower since this wind load could damage ring gears in high wind.
 
Yea,i was thinking that the rotor i posted wasn't rated for what I need. I think I need a heavier duty rotor with a brake. My tower presently has two stacked deep fringe tv antennas on it. The Channel Master 9521a rotor I have only gets about two years use and then starts working erratically and then quits. No brake and not being able to do the job right means a screwed rotor.
P.S. the CP Antenna plans call for a 1 1/2" boom,elements start off with 1" elements that step down to 7/8" then to 3/4" And are saddle clamped to the boom. Add to this a boxes to contain the air-variable capacitors,two 24" gamma matches.
 
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I think if I were you, I'd call Norm at Norm's rotor repair and ask him if he has any rebuilt rotors for sale that would suit your application. The new price on this class of rotors has gone up considerably. Norm is slow but does a good job rebuilding them. I see no reason not to consider a rebuild since he puts new ring gears and meter pots in them. Another option may be to buy a used Ham IV off eBay and send it right to Norm for a checkup or rebuild. The last thing you want to do is get it up and have it fail in a few weeks because it was not checked out properly. Ask me how I know......
 
Shockwave said:
I think if I were you, I'd call Norm at Norm's rotor repair and ask him if he has any rebuilt rotors for sale that would suit your application. The price on this class of rotors has gone up considerably. Norm is slow but does a good job rebuilding them. I see no reason not to consider a rebuild since he puts new ring gears and meter pots in them. Anther option may be to buy a used Ham IV off eBay and send it right to Norm for a checkup or rebuild. The last thing you want to do is get it up and have it fail in a few weeks because it was not checked out properly. Ask me how I know......
Click to expand...

Thanks!
How do you know by the way?
 
In the last two years I've managed to put up a pair of CD-45's that failed shortly after installing only to replace them both with an old Alliance HD-73 that has stood up well. One CD-45 needs a dentist because teeth got ripped off the ring gear and the other had so much use on it that the brass wiper contact for the meter pot wore right trough the contact. Both problems could have easily been avoided if I inspected the inside of the rotors before installing them. Turns out the simple bench test doesn't always reveal all the problems that could be inside waiting to happen.
 
The phasing section and the 1/4 wave coax have .78 VF.
246/frequency in MHz multiplied by .78 VF=7.032435404068169 feet for each 1/4 wavelength section of coax.

Frequency in KHz =(300,000)/ wavelength in meters
Frequency in MHz =(300)/ wavelength in meters Frequency in MHz (984)/ wavelength in Feet
Wavelength in feet=(984)/frequency in MHz
1/4 wave antenna:Length in feet=246 v / frequency in MHz
1/2 wave antenna:Length in feet=492 v / frequency in MHz
 
I did a little more research on the Channel Master 9521A rotator. It looks like I got too much mast to turn. 14' of 1.50" dia. Galvanized plumbing pipe to be exact. The 9521A calls for a max length of 4' and probably the thin gauge stuff. I'm looking at a NTE U-105 with steel gears but something heavier duty with a brake would be the cat's meow.
 
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Rather than making this circular polarized antenna from scratch, does anybody know what would be a good three element beam I could use instead? I thought about using two maco three element beams antennas in a vertical/horizontal configuration but the consensus on maco products is that they use inferior aluminum for their products. Maybe a couple of Sirio three element beams?


P.S. What is a fighting stick?
http://www.antennapartsoutlet.com/Pages/Products/FightingSticks.html
 
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