I wonder if anyone has actually done any studies after all these years on propagation's through this bird. AO-07
I find it in the past couple weeks soo interesting on how varied the level of signal strengths can be on very similar passes.
Where one pass, vs another are almost identical, yet one will be full of stations, and the next one all I hear is my own CQ.
BUT... that difference can be all made by just who is actually on the air.
BUT.... then take two passes that are almost identical, and ignore all the other people, and pay attention to just your own signal, where on this pass my sig is soo weak that 90% of the time I'm hearing nothing, then next pass that is very similar I am actually moving the S meter the signal is sooo strong.
And in theroy, this is all Line Of Sight communications, the losses from one pass vs another should be the same.
Yes polarity can be an issue, but I cant see it being the reason for the whole pass duration.
Very Interesting!
Joe WB9SBD
This sounds like an excellent experiment for you to try and report your results in an article for the AMSAT Journal!
-- 73 de JoAnne K9JKM
----- Original Message ----- From: "Joe" [email protected] To: "amsat-bb" [email protected] Sent: Friday, October 7, 2016 9:11:03 AM Subject: [amsat-bb] AO-07
I wonder if anyone has actually done any studies after all these years on propagation's through this bird. AO-07
I find it in the past couple weeks soo interesting on how varied the level of signal strengths can be on very similar passes.
Where one pass, vs another are almost identical, yet one will be full of stations, and the next one all I hear is my own CQ.
BUT... that difference can be all made by just who is actually on the air.
BUT.... then take two passes that are almost identical, and ignore all the other people, and pay attention to just your own signal, where on this pass my sig is soo weak that 90% of the time I'm hearing nothing, then next pass that is very similar I am actually moving the S meter the signal is sooo strong.
And in theroy, this is all Line Of Sight communications, the losses from one pass vs another should be the same.
Yes polarity can be an issue, but I cant see it being the reason for the whole pass duration.
Very Interesting!
Joe WB9SBD
I would if I had a decent station. I love stuff like this, trying to learn why something is the way it is.
The only thing I can think of is solar weather conditions, Since I should have clarified that I'm talking about Mode "A" here only.
Soo wondering if some ionospheric stuff is effecting the down ward path signal.
OHHH COOL Idea! What a neat idea for a sat!?
A RBN reciever in orbit! and it downloads what it's hearing and just like a regular RBN it also tells signal strengths. hmmmmm?
Joe WB9SBD Sig The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com On 10/7/2016 9:17 AM, JoAnne Maenpaa wrote:
This sounds like an excellent experiment for you to try and report your results in an article for the AMSAT Journal!
-- 73 de JoAnne K9JKM
----- Original Message ----- From: "Joe" [email protected] To: "amsat-bb" [email protected] Sent: Friday, October 7, 2016 9:11:03 AM Subject: [amsat-bb] AO-07
I wonder if anyone has actually done any studies after all these years on propagation's through this bird. AO-07
I find it in the past couple weeks soo interesting on how varied the level of signal strengths can be on very similar passes.
Where one pass, vs another are almost identical, yet one will be full of stations, and the next one all I hear is my own CQ.
BUT... that difference can be all made by just who is actually on the air.
BUT.... then take two passes that are almost identical, and ignore all the other people, and pay attention to just your own signal, where on this pass my sig is soo weak that 90% of the time I'm hearing nothing, then next pass that is very similar I am actually moving the S meter the signal is sooo strong.
And in theroy, this is all Line Of Sight communications, the losses from one pass vs another should be the same.
Yes polarity can be an issue, but I cant see it being the reason for the whole pass duration.
Very Interesting!
Joe WB9SBD
Hi Joe,
My recollection is that there were some informal propagation studies done on the old RS-10/11 and RS-12/13 satellites. I found a few references back in the Amsat archives. See: http://www.amsat.org/amsat/articles/satgen/idx050.html
Good topic needing an update, even an informal one.
Greg KO6TH
Joe wrote:
I wonder if anyone has actually done any studies after all these years on propagation's through this bird. AO-07
I find it in the past couple weeks soo interesting on how varied the level of signal strengths can be on very similar passes.
Where one pass, vs another are almost identical, yet one will be full of stations, and the next one all I hear is my own CQ.
BUT... that difference can be all made by just who is actually on the air.
BUT.... then take two passes that are almost identical, and ignore all the other people, and pay attention to just your own signal, where on this pass my sig is soo weak that 90% of the time I'm hearing nothing, then next pass that is very similar I am actually moving the S meter the signal is sooo strong.
And in theroy, this is all Line Of Sight communications, the losses from one pass vs another should be the same.
Yes polarity can be an issue, but I cant see it being the reason for the whole pass duration.
Very Interesting!
Joe WB9SBD
My first guess would be that because AO-7 is functionally running with no battery, if one station is running high power, it easily hogs all the power available.
Jim K6CCC
-------- Original Message --------
From: "Joe" [email protected] Sent: Friday, October 7, 2016 7:11 AM To: "amsat-bb" [email protected] Subject: [amsat-bb] AO-07
I wonder if anyone has actually done any studies after all these years on propagation's through this bird. AO-07
I find it in the past couple weeks soo interesting on how varied the level of signal strengths can be on very similar passes.
Where one pass, vs another are almost identical, yet one will be full of stations, and the next one all I hear is my own CQ.
BUT... that difference can be all made by just who is actually on the
air.
BUT.... then take two passes that are almost identical, and ignore all the other people, and pay attention to just your own signal, where on this pass my sig is soo weak that 90% of the time I'm hearing nothing, then next pass that is very similar I am actually moving the S meter the signal is sooo strong.
And in theroy, this is all Line Of Sight communications, the losses from one pass vs another should be the same.
Yes polarity can be an issue, but I cant see it being the reason for the whole pass duration.
Very Interesting!
Joe WB9SBD
Sig The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com _______________________________________________ Sent via [email protected]. 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: http://www.amsat.org/mailman/listinfo/amsat-bb
I know this has probably been explained before, but help me understand as this has always puzzled me.
For example purposes I'm going to use 1 watt as the theoretical satellite's output and only one ground station on the input.
The way I understand is: If AO-7 (or any other SSB repeater) receives a signal, it keys up the transmitter side and passes the audio through. If AO-7 transmitter is let's say a 1 watt, then a full quieting signal on the input should make the output max out at 1 watt. If the input signal is weak and noisy, then the output might only be 1/2 watt. Please explain how the repeater's transmitter can put out more than 1 watt (using more power) if the ground station goes well beyond full quieting by uplinking with let's say 500watts.
Thanks in advance for the explanation.
Michael KC4ZVA Sent from my iPad
On Oct 8, 2016, at 7:11 PM, Jim Walls [email protected] wrote:
My first guess would be that because AO-7 is functionally running with no battery, if one station is running high power, it easily hogs all the power available.
Jim K6CCC
-------- Original Message --------
From: "Joe" [email protected] Sent: Friday, October 7, 2016 7:11 AM To: "amsat-bb" [email protected] Subject: [amsat-bb] AO-07
I wonder if anyone has actually done any studies after all these years on propagation's through this bird. AO-07
I find it in the past couple weeks soo interesting on how varied the level of signal strengths can be on very similar passes.
Where one pass, vs another are almost identical, yet one will be full of stations, and the next one all I hear is my own CQ.
BUT... that difference can be all made by just who is actually on the
air.
BUT.... then take two passes that are almost identical, and ignore all the other people, and pay attention to just your own signal, where on this pass my sig is soo weak that 90% of the time I'm hearing nothing, then next pass that is very similar I am actually moving the S meter the signal is sooo strong.
And in theroy, this is all Line Of Sight communications, the losses from one pass vs another should be the same.
Yes polarity can be an issue, but I cant see it being the reason for the whole pass duration.
Very Interesting!
Joe WB9SBD
Sig The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com _______________________________________________ Sent via [email protected]. 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: http://www.amsat.org/mailman/listinfo/amsat-bb
_______________________________________________ Sent via [email protected]. 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: http://www.amsat.org/mailman/listinfo/amsat-bb
Hi Michael,
It can't put out more than what it's capable of, and that's the key here.
First of all, the term "full quieting" signal really only applies to FM transmission. But what you are saying is correct, that once the total of all the uplink signals reaches a point where the corresponding total downlink is "full", more uplink can't change that total.
The point about "hogging" the transponder is that if one of the uplink stations were to increase its power beyond that level, then to maintain the downlink limit, the other stations get their share of the downlink reduced. And with AO-07, if you push it hard enough (not difficult to do), the satellite will crash and reset. The indication that the satellite is running dangerously low on power is when the downlink starts to sound watery ("FM-ing", they call it). More uplink power in this situation will only make things worse.
Greg KO6TH
Mvivona via AMSAT-BB wrote:
I know this has probably been explained before, but help me understand as this has always puzzled me.
For example purposes I'm going to use 1 watt as the theoretical satellite's output and only one ground station on the input.
The way I understand is: If AO-7 (or any other SSB repeater) receives a signal, it keys up the transmitter side and passes the audio through. If AO-7 transmitter is let's say a 1 watt, then a full quieting signal on the input should make the output max out at 1 watt. If the input signal is weak and noisy, then the output might only be 1/2 watt. Please explain how the repeater's transmitter can put out more than 1 watt (using more power) if the ground station goes well beyond full quieting by uplinking with let's say 500watts.
Thanks in advance for the explanation.
Michael KC4ZVA Sent from my iPad
On Oct 8, 2016, at 7:11 PM, Jim Walls [email protected] wrote:
My first guess would be that because AO-7 is functionally running with no battery, if one station is running high power, it easily hogs all the power available.
Jim K6CCC
-------- Original Message --------
From: "Joe" [email protected] Sent: Friday, October 7, 2016 7:11 AM To: "amsat-bb" [email protected] Subject: [amsat-bb] AO-07
I wonder if anyone has actually done any studies after all these years on propagation's through this bird. AO-07
I find it in the past couple weeks soo interesting on how varied the level of signal strengths can be on very similar passes.
Where one pass, vs another are almost identical, yet one will be full of stations, and the next one all I hear is my own CQ.
BUT... that difference can be all made by just who is actually on the
air.
BUT.... then take two passes that are almost identical, and ignore all the other people, and pay attention to just your own signal, where on this pass my sig is soo weak that 90% of the time I'm hearing nothing, then next pass that is very similar I am actually moving the S meter the signal is sooo strong.
And in theroy, this is all Line Of Sight communications, the losses from one pass vs another should be the same.
Yes polarity can be an issue, but I cant see it being the reason for the whole pass duration.
Very Interesting!
Joe WB9SBD
Sig The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com _______________________________________________ Sent via [email protected]. 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: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. 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: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. 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: http://www.amsat.org/mailman/listinfo/amsat-bb
Thank you very much for the explanation Greg.
Michael KC4ZVA Sent from my iPad
On Oct 9, 2016, at 1:49 AM, Greg D [email protected] wrote:
Hi Michael,
It can't put out more than what it's capable of, and that's the key here.
First of all, the term "full quieting" signal really only applies to FM transmission. But what you are saying is correct, that once the total of all the uplink signals reaches a point where the corresponding total downlink is "full", more uplink can't change that total.
The point about "hogging" the transponder is that if one of the uplink stations were to increase its power beyond that level, then to maintain the downlink limit, the other stations get their share of the downlink reduced. And with AO-07, if you push it hard enough (not difficult to do), the satellite will crash and reset. The indication that the satellite is running dangerously low on power is when the downlink starts to sound watery ("FM-ing", they call it). More uplink power in this situation will only make things worse.
Greg KO6TH
Mvivona via AMSAT-BB wrote:
I know this has probably been explained before, but help me understand as this has always puzzled me.
For example purposes I'm going to use 1 watt as the theoretical satellite's output and only one ground station on the input.
The way I understand is: If AO-7 (or any other SSB repeater) receives a signal, it keys up the transmitter side and passes the audio through. If AO-7 transmitter is let's say a 1 watt, then a full quieting signal on the input should make the output max out at 1 watt. If the input signal is weak and noisy, then the output might only be 1/2 watt. Please explain how the repeater's transmitter can put out more than 1 watt (using more power) if the ground station goes well beyond full quieting by uplinking with let's say 500watts.
Thanks in advance for the explanation.
Michael KC4ZVA Sent from my iPad
On Oct 8, 2016, at 7:11 PM, Jim Walls [email protected] wrote:
My first guess would be that because AO-7 is functionally running with no battery, if one station is running high power, it easily hogs all the power available.
Jim K6CCC
-------- Original Message --------
From: "Joe" [email protected] Sent: Friday, October 7, 2016 7:11 AM To: "amsat-bb" [email protected] Subject: [amsat-bb] AO-07
I wonder if anyone has actually done any studies after all these years on propagation's through this bird. AO-07
I find it in the past couple weeks soo interesting on how varied the level of signal strengths can be on very similar passes.
Where one pass, vs another are almost identical, yet one will be full of stations, and the next one all I hear is my own CQ.
BUT... that difference can be all made by just who is actually on the
air.
BUT.... then take two passes that are almost identical, and ignore all the other people, and pay attention to just your own signal, where on this pass my sig is soo weak that 90% of the time I'm hearing nothing, then next pass that is very similar I am actually moving the S meter the signal is sooo strong.
And in theroy, this is all Line Of Sight communications, the losses from one pass vs another should be the same.
Yes polarity can be an issue, but I cant see it being the reason for the whole pass duration.
Very Interesting!
Joe WB9SBD
Sig The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com _______________________________________________ Sent via [email protected]. 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: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. 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: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. 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: http://www.amsat.org/mailman/listinfo/amsat-bb
This is true for all linear transponders, not unique to AO-07. It's the way linear transponders work; the output power is divided among the signals within the passband. Once the total transmit power budget is reached, a station using higher power starts taking power away from the other stations, thus being a hog. With linear transponders, the best way to make your signal louder is to work first on your own receive capability, not the transmit side.
What is a problem with AO-07, however, is that a strong enough station can cause the satellite to use more power than the very old solar panels can provide, and cause the satellite to crash and reset. Please be gentle with this old bird.
Greg KO6TH
Jim Walls wrote:
My first guess would be that because AO-7 is functionally running with no battery, if one station is running high power, it easily hogs all the power available.
Jim K6CCC
-------- Original Message --------
From: "Joe" [email protected] Sent: Friday, October 7, 2016 7:11 AM To: "amsat-bb" [email protected] Subject: [amsat-bb] AO-07
I wonder if anyone has actually done any studies after all these years on propagation's through this bird. AO-07
I find it in the past couple weeks soo interesting on how varied the level of signal strengths can be on very similar passes.
Where one pass, vs another are almost identical, yet one will be full of stations, and the next one all I hear is my own CQ.
BUT... that difference can be all made by just who is actually on the
air.
BUT.... then take two passes that are almost identical, and ignore all the other people, and pay attention to just your own signal, where on this pass my sig is soo weak that 90% of the time I'm hearing nothing, then next pass that is very similar I am actually moving the S meter the signal is sooo strong.
And in theroy, this is all Line Of Sight communications, the losses from one pass vs another should be the same.
Yes polarity can be an issue, but I cant see it being the reason for the whole pass duration.
Very Interesting!
Joe WB9SBD
Sig The Original Rolling Ball Clock Idle Tyme Idle-Tyme.com http://www.idle-tyme.com _______________________________________________ Sent via [email protected]. 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: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via [email protected]. 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: http://www.amsat.org/mailman/listinfo/amsat-bb
participants (5)
-
Greg D -
Jim Walls -
JoAnne Maenpaa -
Joe -
Mvivona