Mike:
Just a quick note on the Yaesu's and square footage ratings. They really
don't tell you a lot.
They use a a K-Factor to determine load. The K Factor is the turning radius
of the antenna multiplied by its weight. The K Factor rating of the G-800
is 1299 ft-lbs. Not sure what the dimensions or weight is of the ham pro
but go through that calculation. The K Factor is more important than the
square footage of the antenna.
I have a G1000SDX and its currently turning a 30' boom C4XL. The rotor is
doing a good job.
Mike Holley wrote:
> Hello ,
> My Name is Mike and I am looking for reliability data from
> present and past users of YAESU Antenna rotors ,in particular the
> G-800SDX model .
> I have had one in service for the last five years during which I have
> had two failures of the control unit and the most recent (This month
> Feb.) of a total destruction of the rotator unit due to gusts of high
> winds (50/60 mph)
> A brief history of the Yaesu G-800SDX
> Purchased in 1994
> Installed in a 70 ft Self supporting tapered tower on a rotor platform
> 6ft below to top of the tower ,
> The antenna (One only) is a 4 element 20 mtr monoband (HAM-PRO) which
> has a published wind surface area of 8.4 sq.ft. (well below the maximum
> capacity of the Yaesu rotor specs of 15 sq.ft) .The antenna was attached
> to the rotor with a 2 inch schedule 40 seamless aluminium heavy wall
> pipe (10')and weight supported by a commercial grade ball race thrust
> bearing which was installed to absorb all the vertical weight of the
> antenna .
> weight and balance was addressed at all times during the installation .
> FAILURE No. 1
> In 1995 (Less than one year after installation the controller failed to
> operate and because of it's complexity (Electronic/Electrical) and No
> Service manual obtainable ) had to be returned to YAESU repair
> department in California .
> A small DC motor and one carbon resistor were found defective and
> replaced
> at a cost of $80.33 Plus S&H
> Failure No. 2
> In 1998 the same two components failed again and had to be replaced at
> a further cost of $81.40 Plus S&H
> FAILURE No.3
> IN 1999 within the last two weeks (Jan.Feb) it was noticed that the
> antenna was wind milling during relative high wind gusts ,it was also
> observed that the co-ax feed line had broken away from the feed point on
> the antenna .
> When the rotator was brought down an opened it was discovered that the
> total electro/mechanical assembly with the one exception the small DC
> drive motor was completely destroyed beyond any possibility of repair .
> The only salvageable parts were ,the upper and lower housing and the
> ball bearing races .
> With an e mail to YAESU with a brief history of what had taken place
> and to enquire if a complete internal sub assembly was available or do
> I have to purchase a whole new rotator minus the controller . The reply
> was that complete sub assemblies were not available but that a
> replacement Rotor less the controller was .
>
> A decision I have to make now is to I replace the Rotor or install
> another brand of rotor . which will entail a lot of tower work .
> I would be most interested to hear from any other YAESU G-800SDX users
> that has experienced any form of problems as this will help me decide on
> the next route to take .
> Thank you one and all for taking the time to read this .
> Respectfully
> Michael Holley VE7AVM
> e mail address <mholley@quik.com>
> 73 - Michael, VE7AVM @ VE7KIT
>
> Message timed: 11:28 on 11 Feb 99
> Message sent using WinPack V6.4
>
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73,
Richard Thorne - N5ZC (Ex. KA2DSY, N2BHP, WB5M)
Amarillo, TX
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