I have my M2 LEO antennas plus a WiMo 23cm helical antenna end-mounted on a fiberglass boom with the G-5500. I also placed a counterbalance lead weight opposite the antennas.
I think I've asked this question before and if so I'm asking it again because, well, I CRS:
How many of you with similar antennas and a G-5500 have NOT used a counterbalance? Any issues?
Bob W7OTJ
I did not use a counter balance. Instead, I mounted the antennas at their balance point on a fiberglass cross-boom.
Rolf NR0T EN34it
On Thu, Apr 2, 2020 at 9:16 AM Bob Hammond via AMSAT-BB amsat-bb@amsat.org wrote:
I have my M2 LEO antennas plus a WiMo 23cm helical antenna end-mounted on a fiberglass boom with the G-5500. I also placed a counterbalance lead weight opposite the antennas.
I think I've asked this question before and if so I'm asking it again because, well, I CRS:
How many of you with similar antennas and a G-5500 have NOT used a counterbalance? Any issues?
Bob W7OTJ _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Bob Hammond asked (in part):
I have my M2 LEO antennas plus a WiMo 23cm helical antenna end-mounted on a fiberglass boom with the G-5500. I also placed a counterbalance lead weight opposite the antennas.
How many of you with similar antennas and a G-5500 have NOT used a counterbalance? Any issues?
I would highly recommend against using any substantial antenna arrangement on an elevation rotor without it being balanced. If it is not balanced, you are putting far more strain on the gears and motor. Try this to understand the difference. Take your antenna, and hold it at one end with one hand. Point it at the horizon. Then rotate it so it points straight up. Now move your hand so it is at the balance point, and repeat the demo. Which one do think is easier? Don't have an antenna handy, use a long piece of pipe, or conduit, or rebar, or even a stick or baseball bat.
73 ----- Jim Walls - K6CCC jim@k6ccc.org
Jim, that's the very reason I installed a counterbalance.
Everyone, my question really was based on what I'm seeing when my antennas rotate in AZ. Given the moment arm of the counterbalance (about 3 feet) and 5 LB weight on the end, once the rotor stops at an azimuth, I get about 3 cycles of wobble back and forth. It does not affect satellite signal (beam width) but I was wondering what it was doing to my rotor gears.
On the other hand, it's been like that for over 6 months of operation with no issues.
It could be I'm finding comfort in worrying about something ELSE at this time....if you get my meaning.
73,
Bob W7OTJ
On Thu, Apr 2, 2020 at 8:13 AM jim--- via AMSAT-BB amsat-bb@amsat.org wrote:
Bob Hammond asked (in part):
I have my M2 LEO antennas plus a WiMo 23cm helical antenna end-mounted
on a
fiberglass boom with the G-5500. I also placed a counterbalance lead weight opposite the antennas.
How many of you with similar antennas and a G-5500 have NOT used a counterbalance? Any issues?
I would highly recommend against using any substantial antenna arrangement on an elevation rotor without it being balanced. If it is not balanced, you are putting far more strain on the gears and motor. Try this to understand the difference. Take your antenna, and hold it at one end with one hand. Point it at the horizon. Then rotate it so it points straight up. Now move your hand so it is at the balance point, and repeat the demo. Which one do think is easier? Don't have an antenna handy, use a long piece of pipe, or conduit, or rebar, or even a stick or baseball bat.
73
Jim Walls - K6CCC jim@k6ccc.org
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
I do not have a counterbalance; I had planned to but somehow just never got to it. I do, however, set my "park" position to be up at 90 degrees. Of course that means the wind tries harder to rotate the elevation rotor, but gravity tries less hard.
That said, I am starting to have a problem. I think it is the feedback pot that is getting noisy, although at first I thought I had stripped a gear. The pot issue should not relate to a counterweight of course!
On Thu, Apr 2, 2020 at 12:27 PM Bob Hammond via AMSAT-BB amsat-bb@amsat.org wrote:
Jim, that's the very reason I installed a counterbalance.
Everyone, my question really was based on what I'm seeing when my antennas rotate in AZ. Given the moment arm of the counterbalance (about 3 feet) and 5 LB weight on the end, once the rotor stops at an azimuth, I get about 3 cycles of wobble back and forth. It does not affect satellite signal (beam width) but I was wondering what it was doing to my rotor gears.
On the other hand, it's been like that for over 6 months of operation with no issues.
It could be I'm finding comfort in worrying about something ELSE at this time....if you get my meaning.
73,
Bob W7OTJ
On Thu, Apr 2, 2020 at 8:13 AM jim--- via AMSAT-BB amsat-bb@amsat.org wrote:
Bob Hammond asked (in part):
I have my M2 LEO antennas plus a WiMo 23cm helical antenna end-mounted
on a
fiberglass boom with the G-5500. I also placed a counterbalance lead weight opposite the antennas.
How many of you with similar antennas and a G-5500 have NOT used a counterbalance? Any issues?
I would highly recommend against using any substantial antenna
arrangement
on an elevation rotor without it being balanced. If it is not balanced, you are putting far more strain on the gears and motor. Try this to understand the difference. Take your antenna, and hold it at one end
with
one hand. Point it at the horizon. Then rotate it so it points straight up. Now move your hand so it is at the balance point, and repeat the demo. Which one do think is easier? Don't have an antenna handy, use a long piece of pipe, or conduit, or rebar, or even a stick or baseball
bat.
73
Jim Walls - K6CCC jim@k6ccc.org
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership.
Opinions
expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite
program!
Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
Jim and group,
Maybe I heard this question differently, I heard, what are the advantages of balancing an antenna in the middle at its balance point, versus closer to the reflective end using a counterweight?
I am also entertaining this option, as the height of my rotor, and thereby the serviceability of the array, are dependent on the length of the back (reflective end) of the antenna). The more antenna behind, the more chance it will hit the ground or roof line.
Michael Hatzakis Jr K3MH
On Apr 2, 2020, at 8:00 AM, jim--- via AMSAT-BB amsat-bb@amsat.org wrote:
Bob Hammond asked (in part):
I have my M2 LEO antennas plus a WiMo 23cm helical antenna end-mounted on a fiberglass boom with the G-5500. I also placed a counterbalance lead weight opposite the antennas.
How many of you with similar antennas and a G-5500 have NOT used a counterbalance? Any issues?
I would highly recommend against using any substantial antenna arrangement on an elevation rotor without it being balanced. If it is not balanced, you are putting far more strain on the gears and motor. Try this to understand the difference. Take your antenna, and hold it at one end with one hand. Point it at the horizon. Then rotate it so it points straight up. Now move your hand so it is at the balance point, and repeat the demo. Which one do think is easier? Don't have an antenna handy, use a long piece of pipe, or conduit, or rebar, or even a stick or baseball bat.
73
Jim Walls - K6CCC jim@k6ccc.org
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
participants (5)
-
Bob Hammond -
Burns Fisher -
jim＠k6ccc.org -
Michael Hatzakis Jr MD -
Rolf Krogstad