[SixClub] [50mhz] The utlimate 6m yagi???

Wed Mar 25 19:30:33 EDT 2009

Richard J. Fiero II W5TFW wrote:
>  Roger,
>
>  You actually have a copyright on your pictures ?
Ever since I found some turning up in adds back in the 70's.
Do you have a QST from Sept 80? (Not related to the adds)
>   MY Hero !  what rotor 
> are you using  for that tower ?
>   
Prosistel/BigBoy PST61. http://www.rogerhalstead.com/Gears.htm  I had to 
modify it a tad as the stock configuration won't fit inside a 45G, but 
all I had to do was rotate the motor 90 degrees so it sticks out the 
side. Mine is one of the older units which has a poor seal arrangement 
that lets water set on the top one. The bearings are actually standard 
car wheel bearings so it'll hold quite a load.  The newer units are much 
improved, however the AlphiSpid made in Canada also uses the dual worm 
gear arrangement and is considerably cheaper IF you don't need the 
torque of the PST 61 or 71.  Neither require a brake as the tremendous 
gear ratio prevents even the largest antenna from wind milling.

BTW, for those who think the 11L 6-meter antenna is a monster, a few 
weeks ago some one posted a link on "Tower Talk" to a site showing IIRC 
a 5L 80 meter Yagi AND a 3L 160 meter Yagi . These are both on towers 
and can be rotated.  You could walk down the inside of the boom on the 
80 meter Yagi.
It's not quite the same but here is a link to a site with some "big 
stuff"  http://www.superbertha.com/

73

Roger (K8RI)
>                                                                                                         
> Joey
>
> Roger (K8RI) wrote:
>   
>> Richard J. Fiero II wrote:
>>   
>>     
>>> HOW would you turn 4 of them ?   with a CAR ?
>>>   
>>>     
>>>       
>> My current system has about twice the wind area of one of those. 
>> http://www.rogerhalstead.com/ham_files/Tower29.htm  <:-))
>>
>> That's not much more than a 3L full size yagi on 40.  Constructing the 
>> "H" frame to hold them would be the biggest task.  then again, it's not 
>> exactly ROHN 25 material either<:-))
>> There are several stock rotators that would handle the quad array.  The 
>> PST71, and the big AlphaSpid should do it.
>>
>> Unfortunately they have a very narrow usable band width. 4 of them would 
>> probably narrow that even more.
>>   
>>     
>>> John Geiger wrote:
>>>   
>>>     
>>>       
>>>> Imagine what stacking 4 of them would do!!! Now that would be a 6m setup.
>>>>
>>>>     
>>>>       
>>>>         
>> Theoretical 20 db gain although it'd be some what less in practice.
>> There are also some down sides such as a very narrow beam width and the 
>> addition of side lobes albeit the first side lobe is down 18 db.  At 38' 
>> wide and 36' high that's about 4 25G sections for a cross boom and 
>> nearly that much on each side for the vertical portions. IOW about 70' 
>> of 25G just to make the H frame. I think they are about 30# each so add 
>> another 210# for the frame plus 332# for 4 antennas so that's 442# for 
>> the antennas an mount. With 10.7 sq ft X 4 = 42.8 sq ft of wind load and 
>> 442#. At roughly$1700 each that's $6800USD just for the antennas (bet 
>> you could get a price break for 4 <g>) Now we have 7 sections of tower 
>> for the H-frame...
>> This is starting to get a bit pricey.
>>
>> I've been looking at moving my tri-bander down the tower to 70' on a 
>> ring rotator (any one know where I can find one at a reasonable price 
>> that will fit a 45G? even if it's used and I have to work on it some). 
>> Then put a 4L heavy duty "shorty fourty" at the top which weighs about 180#.
>>
>> Maybe I could replace my 7L C3i with one, move the tri-bander and then 
>> leave the 144/440 arrays about 15' above the 6 meter yagi. I'd actually 
>> reduce the wind load on the rotator and top of the tower.
>>
>> Then maybe I could just fix what I have, not spend any money on it, and 
>> have a reasonably good system.
>>   
>>     
>>>>> Impressive..BUT look at the specs...83 LBS and 69ft long
>>>>> boom!!! 
>>>>>
>>>>>       
>>>>>         
>>>>>           
>> Ahhh...That's not bad at all.  There's a tribander about 5 miles from 
>> me... actually it's 20-10 with WARC bands That weighs about 240# 
>> although the boom is only 40 some feet.  He hired a crane to come in and 
>> set it.
>>
>>
>>   
>>     
>>>>>  
>>>>>
>>>>> Still, 14dbd on 6m??? YIKES! Don't need a band opening with
>>>>> that monster!!
>>>>>       
>>>>>         
>>>>>           
>> It may be good for weak signal work and Aurora, but unfortunately that's 
>> not enough gain (even as a quad array) to overcome the laws of physics.
>>   
>>     
>>>>> (Oh btw side note to Kelly, N5STK, it will handle 1500watts
>>>>> ;)
>>>>>       
>>>>>         
>>>>>           
>> So it only works on low power? <:-))
>>
>> Oh, to be back out in the country with lots of room, a good job...OK, 
>> I'd rather have a good income without the job.  I'm half way there. I 
>> love retirement, but it could pay a bit better.
>> Enough dreaming...back to the shop...
>>
>> 73
>>
>> Roger (K8RI)
>> ______________________________________________________________
>> SixClub mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/sixclub
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:SixClub at mailman.qth.net
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
>>
>>   
>>     
>
> ______________________________________________________________
> SixClub mailing list
> Home: http://mailman.qth.net/mailman/listinfo/sixclub
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:SixClub at mailman.qth.net
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>   