[MAMS] Wind, spinning yagi's

[Dr. Gerald N. Johnson]

On 4/5/2011 5:46 PM, Lloyd Ellsworth wrote:
> Stan, N8PJP, was a great machinist. He built all of it. Beautifully
> built. Telescoping mast, trailer and all. Really nice portable set up.
> Have no clue what happened to it. Yes, in today's market, it would
> cost a ton. Sorry, I do not have any pix of it. Don't know of any
> cheap, or affordable. However, I can suggest Rover Row at conferences.
> Great place for seeing and exchanging ideas. I really liked how W9FZ
> did it a few years ago at Chicago. Went from rover to rover, and had
> us talk about things. How we were set up. I managed to record some of
> it.

There have been commercially made trailers set up that way, check the 
makers of tilt over and crank up towers. But if you have to ask the 
price, you can't afford one, only the military affords them. To keep 
such a thing from blowing over in a light breeze you have to either have 
long extended legs or lots of ballast weight that makes moving the 
trailer take a 3/4 ton or bigger truck.

Collins used to make such a mast for missle silos. It was just a bit 
overkill for a rover, it had enough hydraulic power to lift a building 
or haavy concrete slab off should an A-Bomb made a direct hit on the silo.

There are fairly long telescoping hydraulic cylinders made for rear dump 
semi trailers, might get to 40' and telescope to 8'. Baum Hudraulics 
used to carry parts to assemble and repair those. They were expected to 
lift 20 or 30 tons, a long more than a few antennas with hydraulic 
power, but if the seals were made to have less friction to only hold air 
pressure of 200 psi they'd probably lift antennas on air pressure.

Then there are scissors lifts and boom trucks that could travel and give 
elevation and if the operator rode up in the bucket, the feed lines 
could be really short!

TV stations use telescoping towers on vans to run microwave links for 
live on the spot news. Once in a while they make their own news 
neglecting to look up before running the mast up under a power line. 
They do replace the van and antenna once in a while.

I was at that W9FZ presentation. Made it hard to keep up with antenna 
measurements going on at the same time, but it was interesting and hard 
to believe the SNR setup.

73, Jerry, K0CQ
>
> My Rover set up. 6M through 1296 are on rover. On a steerable mast.
> This allows me to use a tight parking space, rather than have to aim
> Rover with fixed antennas. And be in a large parking lot or field.
> When I have a driver, I can operate full time. Rover was designed, so
> I can set up on the top platform, and get above the corn fields. Small
> shrubs, etc. Then I have one of two stands, I can use for the higher
> bands. With advance planning, I can put them on top of Rover. Pipe
> extention for the yagi array. Or, I can take my tall saw horse, and
> run it portable. Put the 2M small yagi on top for link, and run that
> way. Takes more than 10 Minutes of set up.
>
> Also, with advance planning, I can set up under the cap on Rover, in
> the rain, if it is not blowing too much. Yes, I do have the "Free"
> Dayton Poncho, which I can put over equipment, and operate. As our New
> England rover friends say. We must be prepared to operate anyway.
>
>
> 73, Lloyd NE8I/r
> EN74 etc
>
>