The Yaesu GA-3000 (I've not seen one) is made for this purpose. You can
make one adapted from a vehicle driveshaft component, often called a flex
disc or a guibo. Also perhaps a LoveJoy or similar coupling, altho the
rubber in these is pretty rigid, I'd like something a little softer. I
have made my own from using heavy duty belting as well. I had 4" mast
sections separated by say 1". Then I wrapped (about 5 turns) the belting
tightly around the mast, bolting it above and below the joint. This lasted
for a few years on the 4 el 80m. I know Denis VE6AQ has made one for his 5
el 40 and his SPID has been handling that antenna for several years without
coming apart. He described his design briefly in his post
http://lists.contesting.com/_towertalk/2001-07/msg00056.html
73 Don
VE6JY
On Tue, Jul 17, 2012 at 12:20 AM, Steve Dyer <w1srd@yahoo.com> wrote:
> What would qualify as a "flexible coupling"?
> 73,
> Steve
> W1SRD
>
>> In my experience, for your situation the standard RAK would be marginally
>> OK for the DB-36 but I'd suggest you use (and maybe you have already) some
>> kind of flexible coupling or a long mast to absorb some of the peak loads.
>> For example, I have been turning a 3 el 40m full size (300-400 lbs
>> approx) with the standard RAK for nearly 10 years BUT I have a long mast
>> to
>> take up the shocks.
>>
>> The important rotor specs are rotating and braking torque. These we can
>> measure simply. Any effort to relate that to the wind load of an antenna,
>> is at best, an educated guess.
>>
>> 73, Don
>> VE6JY
>>
>> On Mon, Jul 16, 2012 at 5:31 PM, Unit365 <unit365@orange.fr> wrote:
>>
>> **
>>>
>>>
>>>
>>> hi
>>>
>>> thanks all for the answer.
>>> Anybody think that a SPID RAK (not the big) could be enouth for the
>>> antenna ? winds hare are often 90km/h and more, but i can put down the
>>> antenna when it’s too windy as i have a tower with trolley. Just a bit
>>> boring because the winch is a turtle and wind is crazy here, coming
>>> leaving
>>> coming.....go up go down......antenna is walking like the dog !! :-)
>>> It’s very hard to comprare some rotators because builders are not using
>>> same units, for example with create.
>>> The alfaspid table don’t contain all rotators.
>>>
>>> Thanks
>>> 73
>>>
>>> Olivier
>>> F4FQH
>>>
>>> From: hb9iqa
>>> Sent: Monday, July 16, 2012 4:58 PM
>>> To: SteppIR@yahoogroups.com
>>> Subject: [SteppIR] Re: Rotators and DB36
>>>
>>> hi oliver
>>>
>>> i use now more then 3 years a create RC 5B-3-P
>>> and I am satisfied.
>>>
>>> 73 de rolf hb9iqa
>>>
>>> --- In mailto:SteppIR%40yahoogroups.**com <SteppIR%2540yahoogroups.com>,
>>> ai4dq@... wrote:
>>>
>>>> Oliver
>>>>
>>>>
>>>> I have a DB-36 and it on TRI- EX Tower 100FT I am using a prop Pitch
>>>> rebuilt by K7NV and a green Heron Controller by K7NV It been through
>>>> 90 MPH storms with out a failure .
>>>>
>>>> 73
>>>> AI4DQ
>>>>
>>>>
>>>> The link is below
>>>>
>>>> _http://www.k7nv.com/**proppitch/_ <http://www.k7nv.com/proppitch/_> (
>>>> http://www.k7nv.com/**proppitch/ <http://www.k7nv.com/proppitch/>)
>>>>
>>>>
>>>>
>>>>
>>>> In a message dated 7/16/2012 10:29:29 A.M. Eastern Daylight Time,
>>>> unit365@... writes:
>>>>
>>>>
>>>>
>>>>
>>>> Hi all
>>>>
>>>> Is there any user of DB36 and what about the rotator are you using with
>>>>
>>> it
>>>
>>>> ?
>>>>
>>>> in project to buy maybe a DB36 and i have the RACK with my 4 ele.
>>>>
>>>> 73
>>>>
>>>> Olivier
>>>> F4FQH
>>>>
>>>> [Non-text portions of this message have been removed]
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> [Non-text portions of this message have been removed]
>>>>
>>>> [Non-text portions of this message have been removed]
>>>
>>>
>>>
>>
>> [Non-text portions of this message have been removed]
>>
>>
>>
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