As I mentioned before, I do not believe it is the pot in the rotor. The meters on your control box read the rotor pot directly. Both the meters and the digital/computer portion read the pot directly. If the meters were erratic or wrong I would suspect the rotor potentiometer. There are 4 alignment pots in the control box. One each for the meter calibration to track the rotor and one each for computer calibration. If you want to check the rotor pot, you can check the three lines that come down from the rotator directly from the pot and see what the the resistance is between three leads as you rotate the elevation rotor. Terminals 1,2 and 3 are directly to the pot. E1 and E3 either side and E2 the center.
Regards,
Reid, W4UPD Amsat #17002
On 2/7/2011 5:51 PM, i8cvs wrote:
----- Original Message ----- From: "Dave Webb KB1PVH"kb1pvh@gmail.com To: "AMSAT -BB"amsat-bb@amsat.org Sent: Monday, February 07, 2011 5:16 PM Subject: [amsat-bb] G5400 elevation issue
The display on the control box reads correct elevation, but on my digital display on the Easy Rotor Controller shows erratic elevation position. I have recalibrated it several times with no success. It won't read any elevation until it is around 20° give or take. It also seems to have become worse since our really cold temps set in. My best guess is the pot in the rotor, but not sure where to start in the process.
Thanks in advance
Dave - KB1PVH
Hi Dave, KB1PVH
If the display on the control box reads correct elevation then the 500 ohm pot into the rotor is OK
By the way if the digital display on the Easy Rotor Controller shows erratic elevation probably the rear potentiometer VR4 in the rear of the control box of the G5400 is set erratic.
Measure the DC voltage between pins 1 and 8 on the external control DIN connector. If the pot VR4 is set correctly the voltage must be 0 volt with elevation = 0° and 2.5 volt with elevation = 90° and 5 volt with elevation 180° i.e. with the antenna completely flipped to 180°
The potentiometer VR4 is located in the rear of the control box as shown in the instruction manual.
Have fun
73" de
i8CVS Domenico
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