[TowerTalk] Effective Moment/K Force & Yaesu rotators

[Pete Smith]

At 12:42 PM 7/11/01 EDT, K7LXC@aol.com wrote:
>    BTW I picked up Yaesu's latest rotator brochure and there have been some 
>changes to the specs. Some of the models now need 6-conductor control cables 
>where they used 5-conductor previously. I heard they changed to DC motors or 
>something like that. Also, the K Force for the G-1000 has been down-graded 
>from 2020 ft-lbs to 1664 ft-lbs.

Before total confusion sets in .... it's true that the G-800 and G-1000
series now say they need a 6-wire control cable.  I've been told that this
was done to meet CE requirements (something to do with a common ground).
In fact, I was told by Yaesu USA (Jerry Darby) that the G-800SA only needs
4 or 5 of the six conductors to operate properly.

Just out of curiosity, I compared the schematic of my G-1000SDX with that
of the G-800/1000SA, and there is virtually no visible commonality.  They
also operate quite differently -- with the G-1000SDX, if there is an open
circuit in the indicator lines to the rotator, the indicator needle is
driven up against the counterclockwise stop, and there have been some
reports of damage to the control box if this went uncorrected for a long
period.  This does not happen with my G-800SA -- in fact, the only
indication of open circuits is that the OVERLAP light goes on, regardless
of position.

Another improvement is that the antenna position at which the overlap light
comes on is now adjustable from the rear.  On the old control boxes it was
not adjustable, and over time, wear on a plastic cam on the indicator shaft
would cause the overlap point to drift. 

As for the K-factor, since it is virtually unrelated to the real moment
felt by the rotator, the change in Yaesu's numbers amounts to nothing more
than a change in the fudge factor.  

73, Pete N4ZR
No, no ... that's WEST Virginia





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