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Maco v quad installation help

This V-quad antenna @ 13 lbs is fairly light weight. However, if you live in a part of this country visited regularly by high winds, it may not be advisable to use the chimney as a mount. Although this beam might be light, its surface area (believe it or not) does provide wind load. The greater the wind; the higher this load will be.

This wind load can also put a great deal of unwanted stress on a rotor too. This side load force can break or shear the rotor housing. The remedy for this is to use a support bearing; and this will handle massive side load forces. i don't use one, as the rotor I am using has quite a bit of overkill for the beam size I am using. But for lesser rotors, $30 for a support bearing is money well spent. Or, you could make one. It doesn't need to have a bearing per se, even a small section of steel tube can be used as an 'axle housing' if you know to use tools and simple hardware.

tb105b.jpg

Source:
http://www.starkelectronic.com/cmmatv.htm#rotor

I use a 35 ft push-up pole attached at the base to the side of my building at two points. Then, guyed at the rotor to four points below with dacron rope. We had some stiff winds here last night here in CA, and the beam did very well. At one time I did consider using the chimney, but felt I just didn't want to risk it.

PICT0306.jpg

Source:
http://www.worldwidedx.com/cb-antennas/91374-sirio-sy27-4-beam-install.html

A push-up pole can be fairly expensive if bought new; the shipping cost can be outrageous. But you can use 36 ft of 1 1/2 in galvanized water pipe; just support it along its length using the building as a support. I cannot foresee a problem with that. Probably 1/3 of the cost of a push-up pole and easier to acquire.

Just some thoughts . . .

(Post #5,000)
 
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I have a TDP-2 rotor.I dont know know the weight on it but it's not heavy.My chimmeny mount is pretty good.Ibrought it from radio shack.Type heavy duty.i will buy another 1 an double up.only 25 bucks.2 BE HONEST I CAN'T AFFORD A TOWER,THANKS GUYS YOUR INPUT MEANS A LOT 2 ME..
 
Inspect your chimney occasionally and look for issues. A lot of dudes are just plain anal about using chimney mounts.

I wouldn't use one on a slate roof though.
 
The transmission line (coax) shield is not part of the antenna or counter poise per say.

Common mode current

Some reading on CMC.

The Gamma match provides a transition from unbalanced coax to balanced antenna. Adjusting the Gamma for lowest Z or VSWR if only a VSWR meter is available will usually eliminate CMC as equal but opposite currents are flowing on the transmission line.

I have never seen a yagi excited with proper drive cause CMC, now I have seen amplifiers being over driven into saturation and beyond cause splatter but the yagi can not be blamed for the splatter, the operator sure can.

I know what CMC is, and I have read that a quad loop will create resistance to CMC, but never a yagi with a gamma.
 
I know what CMC is, and I have read that a quad loop will create resistance to CMC, but never a yagi with a gamma.

HMMM, maybe time for some research in what causes CMC, and with a gamma properly adjusted equal but opposite current flow is distributed.

Enough of hi jacking this thread
 

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