Rob Frohne wrote:
> Bill, et. al.,
>
> I agree that the Ham series rotors will have problems with big antennas,
> however, if you are on a budget and you know about the modes of failure,
> you can make them work. Two of the rules I now go by are:
>
> 1) Never let the antenna coast to a stop anywhere near the rotation
> ends (usually south). In fact, don't turn it close to due south. If
> your beam is large, it has a big moment of inertia, and it will damage
> the stop mechanism.
>
Having used to old Ham series on antennas as large as full size KLM 5L
20 meter and 6 L 15 meter antennas (42 foot booms) I'd add
two points: Don't use the rotator when the wind is strong.
If necessary (as a last resort) use the motor to stop/slowdown one if
you discover the wind is causing it to turn or even accelerate when the
brake is released. Although hard on the motor, it can handle this sort
of thing on an intermittent basis and do so much better than the brake
or stops. Just don't do it often, or for more than a couple of
seconds. IE. Hit reverse and then engage the brake. Even a momentary
pause will allow the brake to engage without tearing things up.
73
Roger (K8RI)
> 2) I don't pin the rotor either, but I do clamp the mast pretty tight.
>
> 3) There are some other things to be aware of, like loose bolts, etc.
>
> I have a web page detailing some of my bad experiences where I learned
> these tips at:
>
> http://people.wallawalla.edu/~Rob.Frohne/Rotor/rotor.html
>
> The best thing about the CDE series or rotors is that they can often be
> found for $100 used, and they are fairly easy to repair if necessary,
> because parts can still be purchased. They can also be upgraded to the
> Ham IV relatively inexpensively if you have a Ham-M, Ham II, or III. I
> also recommend the superwedge from C.A.T.S.
>
> 73,
>
> Rob, KL7NA
>
>
>
> On Mon, 2008-06-02 at 17:33 -0400, Cqtestk4xs@aol.com wrote:
>
>> Although the "Ham" series may be rated at 12.5 and 15 for the Ham 3 and Ham
>> 4, in the real world it ain't so. Having used the 4 series and the
>> Tailtwister for years, experience prevents me from putting anything bigger
>> than a big
>> triabander of around 9-10 on a 4 and nothing much more than around 12 or 13
>> on the Tailtwister..unless of course you want to do gear work on it every
>> couple of years.
>>
>> Cheaping out on the rotor is only for those who like to climb and do rotor
>> replacement.
>>
>> YMMV.
>>
>> Bill KH7XS/K4XS
>>
>>
>>
>> **************Get trade secrets for amazing burgers. Watch "Cooking with
>> Tyler Florence" on AOL Food.
>> (http://food.aol.com/tyler-florence?video=4?&NCID=aolfod00030000000002)
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