[TowerTalk] ALIGNING ANTENNA

[Joe Subich, W4TV]

On 2021-01-01 1:53 PM, Les Brown wrote:

 >     I don't understand why you think it isn't right.

Simply put, the Hy-Gain controller does not have a correction for
magnetic north and the Hy-Gain rotators have only 360 degree rotation.

If the antenna is 30 degrees off alignment and one adjusts the "north"
position using the "calibrate" pot, the heading will be correct at
north but will be off by a variable amount in the rest of the range -
depending on whether the 30 degrees is clockwise or counter clockwise
the indicator will show "south" (assuming the typical north centered
scale) when the rotator is at 210 degrees (CCW limit) and "south" for
180 to 210 degrees (CW limit) or "south" for 150 (CCW limit) to 180
and "south" at 150 (CW limit).

73,

    ... Joe, W4TV


On 2021-01-01 1:53 PM, Les Brown wrote:
> John,
>     I don't understand why you think it isn't right. The magnetic north offset is a fixed offset for a given location. If your correct offset is let's say 10 degrees and you have a misaligned antenna that is another 20 degrees off in the same direction, why not just set the parameter to 30 degrees and not worry about having to physically realign the mast? The only concern I can see is if you don't have enough of a coax loop for the extra rotation.
> 73, Les VE3NNT
> 
> -----Original Message-----
> From: JOHN OWENS [mailto:ham38john at comcast.net]
> Sent: Friday, January 01, 2021 1:04 PM
> To: Les Brown <lesbrown at sympatico.ca>; Dale M. Schwartz <dale at immlawfirm.com>; towertalk at contesting.com
> Subject: Re: [TowerTalk] ALIGNING ANTENNA
> 
> I kinda don't think that is right. Besides, the offset btwn mag and true is unique to each location. -  John Owens -  N7TK
>> On 01/01/2021 9:42 AM Les Brown <lesbrown at sympatico.ca> wrote:
>>
>>   
>> Dale,
>>     Most rotor controllers have an offset for true north vs magnetic north. Why don't you just adjust this parameter?
>> 73, Les VE3NNT
>>
>> -----Original Message-----
>> From: TowerTalk [mailto:towertalk-bounces at contesting.com] On Behalf Of Dale M. Schwartz
>> Sent: Friday, January 01, 2021 12:22 PM
>> To: towertalk at contesting.com
>> Subject: [TowerTalk] ALIGNING ANTENNA
>>
>> I just replaced my rotor (with a HAM-IV) on the bottom of my US Tower 55’ flagpole with a SteppIR on top. The old rotor was off the tower for a few weeks and I suspect the wind blew the beam a little.
>>      Now my bearings are about 30-40 degrees off. So when my controller says I am pointed due North, the beam is actually pointed NNW.
>>      I know we could lower the tower and repoint the beam. But I’m looking for suggestions on how to reorient the antenna from the ground.
>>       Any thoughts would be appreciated.
>>       HAPPY NEW YEAR!
>>                   Dale/K4ROZ
>>