In a message dated 9/26/01 10:46:43 PM Pacific Daylight Time, firstname.lastname@example.org
> I'm currently in the building permit process on what will (hopefully!) be a
> nicely-installed MA-550 crank-up mast. I will be using the MARB-550 rotor
> base with my shiny new Yaesu G-1000DXA rotor.
> I'd like to hear from anyone who has installed one of the U.S. Tower
> MA-series masts and the rotor OR freestanding base regarding their use of
> (or non-use of!) the MAF Series raising fixture. It seems like a good idea
> for installation and working on antennas without having to strap a ladder
> the retracted mast or other scheme. Or...is it a waste of time and money
> once you have the tower installed on the base. I don't plan on changing
> antennas real often. The array will consist of a small-to-medium size HF
> multi-band yagi (type to be determined), a multiband VHF/UHF yagi, and a
> 5-foot omni 2M/440 MHz. vertical. Roof access will be difficult in this
> case, so I will need some way to get to the tower top from ground
> (retracted, about 24') without risking my neck.
I just installed a MA-850, the 85-footer, with the MARB rotating base. We
spent several hours chasing a bind in the rotating system which turned out to
be mostly in the upper collar - there were some high spots that needed to be
filed away. We also spent a bunch of time centering the bottom bearing which
seemed to help the bind problem.
Both bases allow the tower to be tilted-over if you buy the MAF Raising
Fixture. Is the $250 to $500 for the MAF worth adding so you can tilt it
over? You can decide. Unless you do a lot of antenna experimenting, antenna
swapping or do such a crummy job you have to repair your antennas
occasionally, you may not need to use it very often.
OTOH using the MAF Raising Fixture makes it easy to install the tower.
You just get your buddies to haul it in the back yard where you put the hinge
pin through the base and then crank it up into position. Otherwise you have
to conjure up a way to get the tower vertical on the base fixture. (BTW you
don't have enough buddies to pick up the bigger towers.)
So all things considered, it's probably a valuable part of the system.
As far as the Rotor Base vs. the non-rotating base, that's a different
case. I would save the money and put the rotator up on top of the tower. The
only things you get with the rotating base are increased mechanical
complexity and the rotator at the bottom for easy access. The owner of the
aforementioned MA850 said that next time he's skip the rotating tower option
and put the rotator on the top - a simple and less expensive option.
Cheers, Steve K7LXC
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