[TowerTalk] Update on HDR 300 operation question

[James Wolf]

Al,

What I have done with my HDR-300 is to make East the center.  
If you go West of North, the display reads negative, so that it reads -90 degrees.  (-90 degs is the readout limit going CCW). When pointing West going CW it will read the normal 270 degrees. You can calibrate it such that you get 270 degs of correct reading, but then you have to re-calibrate your head when going West of North.  IOW, -10 is really 350 degrees, etc.
Lightning took out the potentiometer a while back and I installed it where East was the middle of the pot range.  

I have also made other modifications.  Brazed the main gear to the shaft, (no more wondering if that key is wearing out).  Brazed a Q-lock onto the bottom of the platform, which will actually clamp the now modified platform to the main shaft and not solely rely on a simple 1/4" key to hold the platform, which it would not do without ruining the rotor shaft key slot. I also mounted the rotor at the 66 ft. level on a 100' tower where the second set of guys are connected with the Rohn torque guy hardware.  This serves two purposes. One is that the long mast pipe absorbs a lot of the start and stop torque as well as a constant wind swing, which can be a rotor-croaker, and it is much easier to climb to 66' than it is to 90 ft.

My potentiometer has failed after about 19 years now, so I will be following in your footsteps as soon as it gets warm enough.

Good Luck,

Jim, KR9U

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Message: 6
Date: Mon, 28 Dec 2009 17:33:33 +0000 (UTC)
From: al_n6ta at comcast.net
Subject: [TowerTalk] Update on HDR 300 operation question
To: TowerTalk <TowerTalk at contesting.com>


All, 

Thanks for the all of the suggestions.? I have since found that there are issues with the documentation on my rotor and its actual build details.? I have reversed two of the pot connections and now get readings, though way off, indicating that the pot's resistance values are off.? I am guessing it relates to it being a 3-turn pot and maybe off by a full turn somehow.? I can deal with that by rotate it 'down form the too high values with the mast clamp loose.? The **range** of resistance varies about as expected.? However, the limit switch stops are not working well and I now need to recalibrate the whole system and may disable them.? Too easy to 'coast by' . 



What really bugs me is that the manual says that '000' is with the actuator arm that hits the limit switches must be exactly half way from full CW and CCW .? This is stated in Section IX for replacement of the pot.? However, I have a manual for this same rotor that shows the actuator in the '000' position just barely touching the CCW limit switch, Figure 4, detail A.? A total discrepancy in the documentation.? This unit is NOT the one that can be centered either North or South.? It never states how it is centered or how to go from NE to NW.? Since I have never run this rotor, I do not know how it is supposed to function and the manual is not good at describing its actual operation.??There are two possibilities. 



1. Start with the actuator in the full CCW position, ready to push the CCW limit switch.? ?I assume '000' is? North.? Running it CW should go to 90 deg, East and on to 180 deg South and after nearly a full rotation of the antenna, I would be at 360 deg, North again.? The actuator should be near the CW limit switch.? The display would be seeing an linear change in pot so the numbers would simple count up from 000 to 360 if the pot and tronix are calibrated.? Seems clear enough.? It does mean that if I want to rotate from 30 deg, Europe for me to 300 deg, JA , I must rotate about 270 deg CW instead of just 90 deg CCW .? I can live with it if this is how it is designed to run and will default to this as my assumption of correct operation. 



2.?Start with?the actuator half way between he stops as the calibration step describes.? Set the pot to read '000' as the manual instructs and assume this to be North.? Then, I can go from North, CW about 180 deg until I reach a limit switch.? That takes me 0 to 180 or South.? Going back to the north, I can continue another 180 deg all the way to the opposite stop, again near 180 but approaching from the other direction.? However, the display will not transition from 000 to 360 and count down to 180.? I assume that?in the old days when this 'fancy' digital display was designed, they had no way to do otherwise.? An analog meter would have worked since its display can easily transition from 000 to 360. 



Anyone want to comment on this basic issue??? Believe me, I am more tired of it than you are! 

Tnx , 

Al 
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