Great YouTube video of a demo of homebrew gyro stabilization hack aboard ISS
http://tinyurl.com/2bldm5 -- 73 de Maggie K3XS Editor, Phil-Mont Mobile Radio Club Blurb - http://www.phil-mont.org Elecraft K2 #1641 -- AOPA 925383 -- ARRL 39280
I'm having a problem with my 5500-azimuth display and control. I haven't used it in a few weeks, tried to work some passes last night and discovered that I lost azimuth control and display. Big problem here is that I had an operation on my shoulder on July 6th and have the use of my left arm only. So I thought I would ask here to try and streamline the repair process. Here are the symptoms...
Elevation works fine in manual or computer control.
Azimuth works in manual mode, but no location information is displayed on control unit or pc software. Also no computer steering , only way to turn is manual input , but no position display.
I tried to tweak the azimuth pots, no joy. Was thinking possible dead spot. Any useful info would be appreciated. Sometimes I wonder if I hit bottom yet in this worst year of my life...
73 Jeff kb2m
Hi Jeff,
It sounds like the feedback pot has gone open circuit on the rotary element. It's connected to the centre solder lug by a flexible lead which stiffens over time and eventually breaks A common problem with the 5500 after a period of use of a couple of years.
The rotator will need to be pulled apart and the pot replaced.
It's happened to quite a few people. Sorry, can't more help from this side of the pond.
73
Dave
On 11 Jul 2007, at 14:01, Jeff Griffin wrote:
I'm having a problem with my 5500-azimuth display and control. I haven't used it in a few weeks, tried to work some passes last night and discovered that I lost azimuth control and display. Big problem here is that I had an operation on my shoulder on July 6th and have the use of my left arm only. So I thought I would ask here to try and streamline the repair process. Here are the symptoms...
Elevation works fine in manual or computer control.
Azimuth works in manual mode, but no location information is displayed on control unit or pc software. Also no computer steering , only way to turn is manual input , but no position display.
I tried to tweak the azimuth pots, no joy. Was thinking possible dead spot. Any useful info would be appreciated. Sometimes I wonder if I hit bottom yet in this worst year of my life...
73 Jeff kb2m
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Hi Jeff,
It sounds like the feedback pot has gone open circuit on the rotary element. It's connected to the centre solder lug by a flexible lead which stiffens over time and eventually breaks A common problem with the 5500 after a period of use of a couple of years.
The rotator will need to be pulled apart and the pot replaced.
It's happened to quite a few people. Sorry, can't more help from this side of the pond.
73
Dave
On 11 Jul 2007, at 14:01, Jeff Griffin wrote:
I'm having a problem with my 5500-azimuth display and control. I haven't used it in a few weeks, tried to work some passes last night and discovered that I lost azimuth control and display. Big problem here is that I had an operation on my shoulder on July 6th and have the use of my left arm only. So I thought I would ask here to try and streamline the repair process. Here are the symptoms...
Elevation works fine in manual or computer control.
Azimuth works in manual mode, but no location information is displayed on control unit or pc software. Also no computer steering , only way to turn is manual input , but no position display.
I tried to tweak the azimuth pots, no joy. Was thinking possible dead spot. Any useful info would be appreciated. Sometimes I wonder if I hit bottom yet in this worst year of my life...
73 Jeff kb2m
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
All: I had same problem with a G5400 several years ago.
I was able to REPAIR the position pot by resoldering the the very flexible lead to the center. I then used a piece of tape to act as a strain relief so that the torque and motion would NOT be transmitted to the solder joint, but would be absorbed over the length of the wire. It has worked fine ever since.
Good luck! 73, Jim wb4gcs@amsat.org
David Johnson wrote:
Hi Jeff,
It sounds like the feedback pot has gone open circuit on the rotary element. It's connected to the centre solder lug by a flexible lead which stiffens over time and eventually breaks A common problem with the 5500 after a period of use of a couple of years.
The rotator will need to be pulled apart and the pot replaced.
It's happened to quite a few people. Sorry, can't more help from this side of the pond.
73
Dave
On 11 Jul 2007, at 14:01, Jeff Griffin wrote:
I'm having a problem with my 5500-azimuth display and control. I haven't used it in a few weeks, tried to work some passes last night and discovered that I lost azimuth control and display. Big problem here is that I had an operation on my shoulder on July 6th and have the use of my left arm only. So I thought I would ask here to try and streamline the repair process. Here are the symptoms...
Elevation works fine in manual or computer control.
Azimuth works in manual mode, but no location information is displayed on control unit or pc software. Also no computer steering , only way to turn is manual input , but no position display.
I tried to tweak the azimuth pots, no joy. Was thinking possible dead spot. Any useful info would be appreciated. Sometimes I wonder if I hit bottom yet in this worst year of my life...
73 Jeff kb2m
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
Jim Sanford wrote:
I was able to REPAIR the position pot by resoldering the the very flexible lead to the center. I then used a piece of tape to act as a strain relief so that the torque and motion would NOT be transmitted to the solder joint, but would be absorbed over the length of the wire. It has worked fine ever since.
A few hours before the start of the January 2006 VHF contest, as I was turning on all my radios, transverters, etc. to get ready, I was horrified to see that the antenna position indicator on my Yaesu G-1000SDX started rotating itself all the way to the stop and stayed there if I used the preset button to tell it to go to any particular azimuth. By turning it off and on, I regained minimal control -- I could turn the antennas, but the position indicator stayed at the stop no matter where the antennas pointed. I figured I was screwed, as I had no intention of falling off an icy roof to climb my rooftop tower in the middle of a Minnesota winter, and even if I did, there would be no way I'd repair the thing in time for the contest, and no way I'd get one of my kids to volunteer to stand out in the cold and tell me which way the antennas were pointed every time I wanted to aim in a new direction.
Then, as I was preparing to shut everything off and give up, I was looking at the tangled mess of cables behind my stack of radio gear, and much to my surprise, found that the rotator cable plug was not seated firmly into the back of the rotator controller. I pushed it all the way in, and it has worked perfectly ever since. Apparently the connection was "good enough" to the lines that controlled the rotation motors, but not "good enough" to the line that brings back the feedback potentiometer setting.
Maybe, just MAYBE, you will get lucky that way too. It certainly costs nothing to check!
73 de W0JT
Hi Jeff, KB2M
Despite the problem on your shoulder you can locate the fault on your azimuth control and display just from the shak.
Without disconnecting any wire from the back of your control box connect a DC voltmeter between terminals A1 and A3 and you should read about 5.5 volt DC
Connect the DC voltmeter between terminals A2 and A3
When the antenna is rotated fully CCW you should read 0 volt and rotating the antenna by 360° CW the voltage should linearly increase up to about 5.5 volt
If you pass the above test than the 500 ohm potentiometer inside the rotator is OK
If not or the potentiometer is gone or one of the wires A1-A2-A3 running from the control box to the antenna is interrupded.
To test if the control box alone is OK or not disconnect wires A1-A2-A3 from the rear of control box and connect to it a 500 ohm wire wound potentiometer to simulate the potentiometer inside the rotator.
Manually turning the above potentiometer you should have the angular position information of the pot wiper (A2 wire) both on control box meter and PC software.
Have fun !
73" de
i8CVS Domenico
----- Original Message ----- From: "Jeff Griffin" kb2m@comcast.net To: "Amsat-Bb" amsat-bb@amsat.org Sent: Wednesday, July 11, 2007 3:01 PM Subject: [amsat-bb] Yaesu 5500 rotor problem
I'm having a problem with my 5500-azimuth display and control. I haven't used it in a few weeks, tried to work some passes last night and
discovered
that I lost azimuth control and display. Big problem here is that I had an operation on my shoulder on July 6th and have the use of my left arm only. So I thought I would ask here to try and streamline the repair process.
Here
are the symptoms...
Elevation works fine in manual or computer control.
Azimuth works in manual mode, but no location information is displayed on control unit or pc software. Also no computer steering , only way to turn
is
manual input , but no position display.
I tried to tweak the azimuth pots, no joy. Was thinking possible dead
spot.
Any useful info would be appreciated. Sometimes I wonder if I hit bottom
yet
in this worst year of my life...
73 Jeff kb2m
participants (6)
-
David Johnson -
i8cvs -
Jeff Griffin -
Jim Sanford -
John P. Toscano -
Margaret Leber