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CX2SA > SATDIG 28.03.18 04:41l 1327 Lines 47610 Bytes #999 (0) @ WW
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To : SATDIG@WW
Today's Topics:
1. Re: AO-92 fading (Mark L. Hammond)
2. Re: AO-92 fading (Sterling Coffey)
3. Re: AO-92 fading (Stefan Wagener)
4. Re: AO-92 fading (Zach Metzinger)
5. Re: AO-92 fading (Stefan Wagener)
6. Re: AO-92 fading (Sterling Coffey)
7. Re: AO-92 fading (Stephen E. Belter)
----------------------------------------------------------------------
Message: 1
Date: Wed, 28 Mar 2018 01:46:36 +0000
From: "Mark L. Hammond" <marklhammond@?????.???>
To: Sterling Coffey <kawfey@?????.???>
Cc: Paul Stoetzer <n8hm@????.???>, Burns Fisher <burns@??????.??>,
amsat-bb <amsat-bb@?????.???>
Subject: Re: [amsat-bb] AO-92 fading
Message-ID:
<CAPRXzyrUwYQUvgVi_C33b4AiyrjKSHO2_qqnjv1yQ5Ar6PRLFA@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
The telemetry nuts should have some idea. Independent of any uplink. Good
SDR recording exercise and study.
Mark N8MH
On Tue, Mar 27, 2018 at 9:41 PM Sterling Coffey <kawfey@?????.???> wrote:
> You can hear your own signal if you have a full duplex (two radio) setup.
> However, it's still pretty hard to tell if you use a single antenna (arrow,
> elk, etc) since you're changing the RX polarity while you're changing the
> TX polarity too.
>
> On Tue, Mar 27, 2018 at 7:22 PM, Stefan Wagener <wageners@?????.???>
> wrote:
>
> > One of the questions I have is why one would think that the uplink
> > (polarization) is a problem since you only have the downlink to assess
> and
> > how would you differentiate between uplink "weakness" from downlink since
> > that is the only thing you hear. In addition, at least for uplink, you
> > could "in principle" very quickly adjust with higher power... and no, I
> am
> > NOT promoting crocodile behavior (big mouth little ears)
> >
> > Stefan, VE4NSA
> >
> > On Tue, Mar 27, 2018 at 2:26 PM, Burns Fisher <burns@??????.??> wrote:
> >
> > > If you have seen a model or picture of the Fox satellites, you may have
> > > noticed that some of the solar panels seem to be mounted off-center.
> > This
> > > is intentional so that photons that reflect off the shiny side give it
> a
> > > tiny off-center push that spins the bird to distribute the heat more
> > > evenly. Thus it spins faster the more time it spends in the sun. In
> > > addition, when it crosses the equator, it should flip over (-Z and +Z
> > > reverse sides). This is because of the passive magnetic stabilization.
> > > But I'm guessing that since it is spinning, that causes it to wobble.
> > >
> > > Why 92 seems worse I don't know--I can only assume it has something to
> do
> > > with the orbit. That graph that Paul posted looks very different from
> > > AO-85, for example.
> > >
> > > Some RF person can correct me, but I believe that the 70cm antenna only
> > > uses the antenna that sticks out one side, while the 2m antenna
> actually
> > > uses the antennas on both sides. Could that explain why the uplink has
> > > more fading than the downlink? I don't know. Something to think
> about.
> > >
> > > 73,
> > >
> > > Burns WB1FJ
> > > Fox-1 Flight Software
> > >
> > > On Tue, Mar 27, 2018 at 2:12 PM, Paul Stoetzer <n8hm@????.???> wrote:
> > >
> > > > All of the Fox-1 satellites seem to spin faster or slower depending
> on
> > > > orbit illumination or other factors.
> > > >
> > > > For example, this is the +Z panel rotation on AO-92 since launch.
> > > >
> > > > https://imgur.com/a/uS8TB
> > > >
> > > > Someone more well-versed in these matters can comment further on what
> > > > causes this, but it is definitely not an indication of the health
> > > > status of the satellite.
> > > >
> > > > 73,
> > > >
> > > > Paul, N8HM
> > > >
> > > > On Tue, Mar 27, 2018 at 1:59 PM, Jean Marc Momple
> > > > <jean.marc.momple@?????.???> wrote:
> > > > > Dear All,
> > > > >
> > > > > I have been experimenting with AO-92 as from its launch. Some
> > > > observations:
> > > > >
> > > > > 1) The fading on this bird seems to be high and quite
> unpredictable,
> > > > requires a lot of changes of polarization to keep the Rx signal to
> an
> > > > adequate level.
> > > > >
> > > > > 2) Seems that the fading is both on the U/V and L-mode, more seems
> to
> > > me
> > > > that the uplink is more affected.
> > > > >
> > > > > 3) Telemetry seems to be quite reliable with FoxTelem in all modes.
> > > > >
> > > > > Today, it was even worse losing the bird many times during the
> pass,
> > it
> > > > seems that it is degrading quite quickly, hope that this is not the
> > case.
> > > > >
> > > > > Just to share my observation.
> > > > >
> > > > > 73
> > > > >
> > > > >
> > > > > Jean Marc (3B8du)
> > > > >
> > > > >
> > > > > _______________________________________________
> > > > > Sent via AMSAT-BB@?????.???. 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 AMSAT-BB@?????.???. 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 AMSAT-BB@?????.???. 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 AMSAT-BB@?????.???. 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 AMSAT-BB@?????.???. 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
>
--
Mark L. Hammond [N8MH]
------------------------------
Message: 2
Date: Tue, 27 Mar 2018 20:47:11 -0500
From: Sterling Coffey <kawfey@?????.???>
To: Stefan Wagener <wageners@?????.???>
Cc: Paul Stoetzer <n8hm@????.???>, amsat-bb <amsat-bb@?????.???>,
Burns Fisher <burns@??????.??>
Subject: Re: [amsat-bb] AO-92 fading
Message-ID:
<CACxCfFodsnbtAvmoWh0nR-rg7G=MujgJ7QzjBGQzBeKhsuiUdQ@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
If linear polarized, if you can keep your RX/downlink antenna still and you
can at least hear the satellite, and rotating your TX/uplink antenna
results in correlated signal level changes on the RX/downlink, then you've
isolated it to the uplink polarization variable.
On Tue, Mar 27, 2018 at 8:44 PM, Stefan Wagener <wageners@?????.???> wrote:
> Thanks,
>
> Again, even in full duplex how do you distinguish between a non-matching
> uplink vs non-matching downlink? You only "hear" the downlink!
>
> 73, Stefan VE4NSA
>
> On Tue, Mar 27, 2018 at 8:38 PM, Sterling Coffey <kawfey@?????.???> wrote:
>
>> You can hear your own signal if you have a full duplex (two radio) setup.
>> However, it's still pretty hard to tell if you use a single antenna (arrow,
>> elk, etc) since you're changing the RX polarity while you're changing the
>> TX polarity too.
>>
>> On Tue, Mar 27, 2018 at 7:22 PM, Stefan Wagener <wageners@?????.???>
>> wrote:
>>
>>> One of the questions I have is why one would think that the uplink
>>> (polarization) is a problem since you only have the downlink to assess
>>> and
>>> how would you differentiate between uplink "weakness" from downlink since
>>> that is the only thing you hear. In addition, at least for uplink, you
>>> could "in principle" very quickly adjust with higher power... and no, I
>>> am
>>> NOT promoting crocodile behavior (big mouth little ears)
>>>
>>> Stefan, VE4NSA
>>>
>>> On Tue, Mar 27, 2018 at 2:26 PM, Burns Fisher <burns@??????.??> wrote:
>>>
>>> > If you have seen a model or picture of the Fox satellites, you may have
>>> > noticed that some of the solar panels seem to be mounted off-center.
>>> This
>>> > is intentional so that photons that reflect off the shiny side give it
>>> a
>>> > tiny off-center push that spins the bird to distribute the heat more
>>> > evenly. Thus it spins faster the more time it spends in the sun. In
>>> > addition, when it crosses the equator, it should flip over (-Z and +Z
>>> > reverse sides). This is because of the passive magnetic stabilization.
>>> > But I'm guessing that since it is spinning, that causes it to wobble.
>>> >
>>> > Why 92 seems worse I don't know--I can only assume it has something to
>>> do
>>> > with the orbit. That graph that Paul posted looks very different from
>>> > AO-85, for example.
>>> >
>>> > Some RF person can correct me, but I believe that the 70cm antenna only
>>> > uses the antenna that sticks out one side, while the 2m antenna
>>> actually
>>> > uses the antennas on both sides. Could that explain why the uplink has
>>> > more fading than the downlink? I don't know. Something to think
>>> about.
>>> >
>>> > 73,
>>> >
>>> > Burns WB1FJ
>>> > Fox-1 Flight Software
>>> >
>>> > On Tue, Mar 27, 2018 at 2:12 PM, Paul Stoetzer <n8hm@????.???> wrote:
>>> >
>>> > > All of the Fox-1 satellites seem to spin faster or slower depending
>>> on
>>> > > orbit illumination or other factors.
>>> > >
>>> > > For example, this is the +Z panel rotation on AO-92 since launch.
>>> > >
>>> > > https://imgur.com/a/uS8TB
>>> > >
>>> > > Someone more well-versed in these matters can comment further on what
>>> > > causes this, but it is definitely not an indication of the health
>>> > > status of the satellite.
>>> > >
>>> > > 73,
>>> > >
>>> > > Paul, N8HM
>>> > >
>>> > > On Tue, Mar 27, 2018 at 1:59 PM, Jean Marc Momple
>>> > > <jean.marc.momple@?????.???> wrote:
>>> > > > Dear All,
>>> > > >
>>> > > > I have been experimenting with AO-92 as from its launch. Some
>>> > > observations:
>>> > > >
>>> > > > 1) The fading on this bird seems to be high and quite
>>> unpredictable,
>>> > > requires a lot of changes of polarization to keep the Rx signal to
>>> an
>>> > > adequate level.
>>> > > >
>>> > > > 2) Seems that the fading is both on the U/V and L-mode, more seems
>>> to
>>> > me
>>> > > that the uplink is more affected.
>>> > > >
>>> > > > 3) Telemetry seems to be quite reliable with FoxTelem in all modes.
>>> > > >
>>> > > > Today, it was even worse losing the bird many times during the
>>> pass, it
>>> > > seems that it is degrading quite quickly, hope that this is not the
>>> case.
>>> > > >
>>> > > > Just to share my observation.
>>> > > >
>>> > > > 73
>>> > > >
>>> > > >
>>> > > > Jean Marc (3B8du)
>>> > > >
>>> > > >
>>> > > > _______________________________________________
>>> > > > Sent via AMSAT-BB@?????.???. 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/l
>>> istinfo/amsat-bb
>>> > > _______________________________________________
>>> > > Sent via AMSAT-BB@?????.???. 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/l
>>> istinfo/amsat-bb
>>> > >
>>> > _______________________________________________
>>> > Sent via AMSAT-BB@?????.???. 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 AMSAT-BB@?????.???. 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
>>>
>>
>>
>
------------------------------
Message: 3
Date: Tue, 27 Mar 2018 20:49:10 -0500
From: Stefan Wagener <wageners@?????.???>
To: "Mark L. Hammond" <marklhammond@?????.???>
Cc: Paul Stoetzer <n8hm@????.???>, amsat-bb <amsat-bb@?????.???>,
Burns Fisher <burns@??????.??>
Subject: Re: [amsat-bb] AO-92 fading
Message-ID:
<CAKu8kHDWk6NGmPR4AHT+Sx10nb+=r38vVBwe+jUPMMSgxmTG_w@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
Thanks Mark!
Even a good SDR recording exercise only captures the downlink :-)
Stefran
On Tue, Mar 27, 2018 at 8:46 PM, Mark L. Hammond <marklhammond@?????.???>
wrote:
> The telemetry nuts should have some idea. Independent of any uplink.
> Good SDR recording exercise and study.
>
> Mark N8MH
>
> On Tue, Mar 27, 2018 at 9:41 PM Sterling Coffey <kawfey@?????.???> wrote:
>
>> You can hear your own signal if you have a full duplex (two radio) setup.
>> However, it's still pretty hard to tell if you use a single antenna
>> (arrow,
>> elk, etc) since you're changing the RX polarity while you're changing the
>> TX polarity too.
>>
>> On Tue, Mar 27, 2018 at 7:22 PM, Stefan Wagener <wageners@?????.???>
>> wrote:
>>
>> > One of the questions I have is why one would think that the uplink
>> > (polarization) is a problem since you only have the downlink to assess
>> and
>> > how would you differentiate between uplink "weakness" from downlink
>> since
>> > that is the only thing you hear. In addition, at least for uplink, you
>> > could "in principle" very quickly adjust with higher power... and no, I
>> am
>> > NOT promoting crocodile behavior (big mouth little ears)
>> >
>> > Stefan, VE4NSA
>> >
>> > On Tue, Mar 27, 2018 at 2:26 PM, Burns Fisher <burns@??????.??> wrote:
>> >
>> > > If you have seen a model or picture of the Fox satellites, you may
>> have
>> > > noticed that some of the solar panels seem to be mounted off-center.
>> > This
>> > > is intentional so that photons that reflect off the shiny side give
>> it a
>> > > tiny off-center push that spins the bird to distribute the heat more
>> > > evenly. Thus it spins faster the more time it spends in the sun. In
>> > > addition, when it crosses the equator, it should flip over (-Z and +Z
>> > > reverse sides). This is because of the passive magnetic
>> stabilization.
>> > > But I'm guessing that since it is spinning, that causes it to wobble.
>> > >
>> > > Why 92 seems worse I don't know--I can only assume it has something
>> to do
>> > > with the orbit. That graph that Paul posted looks very different from
>> > > AO-85, for example.
>> > >
>> > > Some RF person can correct me, but I believe that the 70cm antenna
>> only
>> > > uses the antenna that sticks out one side, while the 2m antenna
>> actually
>> > > uses the antennas on both sides. Could that explain why the uplink
>> has
>> > > more fading than the downlink? I don't know. Something to think
>> about.
>> > >
>> > > 73,
>> > >
>> > > Burns WB1FJ
>> > > Fox-1 Flight Software
>> > >
>> > > On Tue, Mar 27, 2018 at 2:12 PM, Paul Stoetzer <n8hm@????.???> wrote:
>> > >
>> > > > All of the Fox-1 satellites seem to spin faster or slower depending
>> on
>> > > > orbit illumination or other factors.
>> > > >
>> > > > For example, this is the +Z panel rotation on AO-92 since launch.
>> > > >
>> > > > https://imgur.com/a/uS8TB
>> > > >
>> > > > Someone more well-versed in these matters can comment further on
>> what
>> > > > causes this, but it is definitely not an indication of the health
>> > > > status of the satellite.
>> > > >
>> > > > 73,
>> > > >
>> > > > Paul, N8HM
>> > > >
>> > > > On Tue, Mar 27, 2018 at 1:59 PM, Jean Marc Momple
>> > > > <jean.marc.momple@?????.???> wrote:
>> > > > > Dear All,
>> > > > >
>> > > > > I have been experimenting with AO-92 as from its launch. Some
>> > > > observations:
>> > > > >
>> > > > > 1) The fading on this bird seems to be high and quite
>> unpredictable,
>> > > > requires a lot of changes of polarization to keep the Rx signal to
>> an
>> > > > adequate level.
>> > > > >
>> > > > > 2) Seems that the fading is both on the U/V and L-mode, more
>> seems to
>> > > me
>> > > > that the uplink is more affected.
>> > > > >
>> > > > > 3) Telemetry seems to be quite reliable with FoxTelem in all
>> modes.
>> > > > >
>> > > > > Today, it was even worse losing the bird many times during the
>> pass,
>> > it
>> > > > seems that it is degrading quite quickly, hope that this is not the
>> > case.
>> > > > >
>> > > > > Just to share my observation.
>> > > > >
>> > > > > 73
>> > > > >
>> > > > >
>> > > > > Jean Marc (3B8du)
>> > > > >
>> > > > >
>> > > > > _______________________________________________
>> > > > > Sent via AMSAT-BB@?????.???. 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 AMSAT-BB@?????.???. 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 AMSAT-BB@?????.???. 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 AMSAT-BB@?????.???. 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 AMSAT-BB@?????.???. 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
>>
> --
> Mark L. Hammond [N8MH]
>
------------------------------
Message: 4
Date: Tue, 27 Mar 2018 20:50:53 -0500
From: Zach Metzinger <zmetzing@?????.???>
To: amsat-bb@?????.???
Subject: Re: [amsat-bb] AO-92 fading
Message-ID: <b567f94b-2ac7-6323-bb39-808d4f605ad6@?????.???>
Content-Type: text/plain; charset=utf-8; format=flowed
On 03/27/18 20:44, Stefan Wagener wrote:
> Thanks,
>
> Again, even in full duplex how do you distinguish between a non-matching
> uplink vs non-matching downlink? You only "hear" the downlink!
I suppose that, if you had really good antennas and preamps, you might
be able to hear your reflected uplink signal, no? :-)
--- Zach
N0ZGO
------------------------------
Message: 5
Date: Tue, 27 Mar 2018 20:54:09 -0500
From: Stefan Wagener <wageners@?????.???>
To: Sterling Coffey <kawfey@?????.???>
Cc: Paul Stoetzer <n8hm@????.???>, amsat-bb <amsat-bb@?????.???>,
Burns Fisher <burns@??????.??>
Subject: Re: [amsat-bb] AO-92 fading
Message-ID:
<CAKu8kHAZ4gG+WaAg52kzs2jgU9usThDQqm_RyUmuDSRyBEsiaw@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
Hi Sterling,
That would assume you have the ability to switch between linear uplink
polarization (vertical and horizontal) and circular polarisation for uplink
(right and left) and keep you downlink polarization on the same
optimized path all the time, meaning you know in advance which way the
downlink signal is the best to compensate for any uplink discrepancies.
Good luck :-)
But hanks, good thought!
Stefan, VE4NSA
On Tue, Mar 27, 2018 at 8:47 PM, Sterling Coffey <kawfey@?????.???> wrote:
> If linear polarized, if you can keep your RX/downlink antenna still and
> you can at least hear the satellite, and rotating your TX/uplink antenna
> results in correlated signal level changes on the RX/downlink, then you've
> isolated it to the uplink polarization variable.
>
> On Tue, Mar 27, 2018 at 8:44 PM, Stefan Wagener <wageners@?????.???>
> wrote:
>
>> Thanks,
>>
>> Again, even in full duplex how do you distinguish between a non-matching
>> uplink vs non-matching downlink? You only "hear" the downlink!
>>
>> 73, Stefan VE4NSA
>>
>> On Tue, Mar 27, 2018 at 8:38 PM, Sterling Coffey <kawfey@?????.???>
>> wrote:
>>
>>> You can hear your own signal if you have a full duplex (two radio)
>>> setup. However, it's still pretty hard to tell if you use a single antenna
>>> (arrow, elk, etc) since you're changing the RX polarity while you're
>>> changing the TX polarity too.
>>>
>>> On Tue, Mar 27, 2018 at 7:22 PM, Stefan Wagener <wageners@?????.???>
>>> wrote:
>>>
>>>> One of the questions I have is why one would think that the uplink
>>>> (polarization) is a problem since you only have the downlink to assess
>>>> and
>>>> how would you differentiate between uplink "weakness" from downlink
>>>> since
>>>> that is the only thing you hear. In addition, at least for uplink, you
>>>> could "in principle" very quickly adjust with higher power... and no, I
>>>> am
>>>> NOT promoting crocodile behavior (big mouth little ears)
>>>>
>>>> Stefan, VE4NSA
>>>>
>>>> On Tue, Mar 27, 2018 at 2:26 PM, Burns Fisher <burns@??????.??> wrote:
>>>>
>>>> > If you have seen a model or picture of the Fox satellites, you may
>>>> have
>>>> > noticed that some of the solar panels seem to be mounted off-center.
>>>> This
>>>> > is intentional so that photons that reflect off the shiny side give
>>>> it a
>>>> > tiny off-center push that spins the bird to distribute the heat more
>>>> > evenly. Thus it spins faster the more time it spends in the sun. In
>>>> > addition, when it crosses the equator, it should flip over (-Z and +Z
>>>> > reverse sides). This is because of the passive magnetic
>>>> stabilization.
>>>> > But I'm guessing that since it is spinning, that causes it to wobble.
>>>> >
>>>> > Why 92 seems worse I don't know--I can only assume it has something
>>>> to do
>>>> > with the orbit. That graph that Paul posted looks very different from
>>>> > AO-85, for example.
>>>> >
>>>> > Some RF person can correct me, but I believe that the 70cm antenna
>>>> only
>>>> > uses the antenna that sticks out one side, while the 2m antenna
>>>> actually
>>>> > uses the antennas on both sides. Could that explain why the uplink
>>>> has
>>>> > more fading than the downlink? I don't know. Something to think
>>>> about.
>>>> >
>>>> > 73,
>>>> >
>>>> > Burns WB1FJ
>>>> > Fox-1 Flight Software
>>>> >
>>>> > On Tue, Mar 27, 2018 at 2:12 PM, Paul Stoetzer <n8hm@????.???> wrote:
>>>> >
>>>> > > All of the Fox-1 satellites seem to spin faster or slower depending
>>>> on
>>>> > > orbit illumination or other factors.
>>>> > >
>>>> > > For example, this is the +Z panel rotation on AO-92 since launch.
>>>> > >
>>>> > > https://imgur.com/a/uS8TB
>>>> > >
>>>> > > Someone more well-versed in these matters can comment further on
>>>> what
>>>> > > causes this, but it is definitely not an indication of the health
>>>> > > status of the satellite.
>>>> > >
>>>> > > 73,
>>>> > >
>>>> > > Paul, N8HM
>>>> > >
>>>> > > On Tue, Mar 27, 2018 at 1:59 PM, Jean Marc Momple
>>>> > > <jean.marc.momple@?????.???> wrote:
>>>> > > > Dear All,
>>>> > > >
>>>> > > > I have been experimenting with AO-92 as from its launch. Some
>>>> > > observations:
>>>> > > >
>>>> > > > 1) The fading on this bird seems to be high and quite
>>>> unpredictable,
>>>> > > requires a lot of changes of polarization to keep the Rx signal to
>>>> an
>>>> > > adequate level.
>>>> > > >
>>>> > > > 2) Seems that the fading is both on the U/V and L-mode, more
>>>> seems to
>>>> > me
>>>> > > that the uplink is more affected.
>>>> > > >
>>>> > > > 3) Telemetry seems to be quite reliable with FoxTelem in all
>>>> modes.
>>>> > > >
>>>> > > > Today, it was even worse losing the bird many times during the
>>>> pass, it
>>>> > > seems that it is degrading quite quickly, hope that this is not the
>>>> case.
>>>> > > >
>>>> > > > Just to share my observation.
>>>> > > >
>>>> > > > 73
>>>> > > >
>>>> > > >
>>>> > > > Jean Marc (3B8du)
>>>> > > >
>>>> > > >
>>>> > > > _______________________________________________
>>>> > > > Sent via AMSAT-BB@?????.???. 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/l
>>>> istinfo/amsat-bb
>>>> > > _______________________________________________
>>>> > > Sent via AMSAT-BB@?????.???. 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/l
>>>> istinfo/amsat-bb
>>>> > >
>>>> > _______________________________________________
>>>> > Sent via AMSAT-BB@?????.???. 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 AMSAT-BB@?????.???. 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
>>>>
>>>
>>>
>>
>
------------------------------
Message: 6
Date: Tue, 27 Mar 2018 21:08:36 -0500
From: Sterling Coffey <kawfey@?????.???>
To: Stefan Wagener <wageners@?????.???>
Cc: Paul Stoetzer <n8hm@????.???>, amsat-bb <amsat-bb@?????.???>,
Burns Fisher <burns@??????.??>
Subject: Re: [amsat-bb] AO-92 fading
Message-ID:
<CACxCfFqU6SHqon9Ac7KRUBGMB0xFzZeMbDAXNLTin7g4f5ooGg@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
I'm specifically thinking of handheld linear antennas; I'm pretty sure you
can rotate the RX antenna pol for "maximum smoke" and then the TX antenna
faster than the tumbling rate of the satellite just to get an idea of which
path is being affected.
This is a moot point though, most of us use Arrow antennas anyway!
On Tue, Mar 27, 2018 at 8:54 PM, Stefan Wagener <wageners@?????.???> wrote:
> Hi Sterling,
>
> That would assume you have the ability to switch between linear uplink
> polarization (vertical and horizontal) and circular polarisation for uplink
> (right and left) and keep you downlink polarization on the same
> optimized path all the time, meaning you know in advance which way the
> downlink signal is the best to compensate for any uplink discrepancies.
> Good luck :-)
>
> But hanks, good thought!
>
> Stefan, VE4NSA
>
> On Tue, Mar 27, 2018 at 8:47 PM, Sterling Coffey <kawfey@?????.???> wrote:
>
>> If linear polarized, if you can keep your RX/downlink antenna still and
>> you can at least hear the satellite, and rotating your TX/uplink antenna
>> results in correlated signal level changes on the RX/downlink, then you've
>> isolated it to the uplink polarization variable.
>>
>> On Tue, Mar 27, 2018 at 8:44 PM, Stefan Wagener <wageners@?????.???>
>> wrote:
>>
>>> Thanks,
>>>
>>> Again, even in full duplex how do you distinguish between a non-matching
>>> uplink vs non-matching downlink? You only "hear" the downlink!
>>>
>>> 73, Stefan VE4NSA
>>>
>>> On Tue, Mar 27, 2018 at 8:38 PM, Sterling Coffey <kawfey@?????.???>
>>> wrote:
>>>
>>>> You can hear your own signal if you have a full duplex (two radio)
>>>> setup. However, it's still pretty hard to tell if you use a single
antenna
>>>> (arrow, elk, etc) since you're changing the RX polarity while you're
>>>> changing the TX polarity too.
>>>>
>>>> On Tue, Mar 27, 2018 at 7:22 PM, Stefan Wagener <wageners@?????.???>
>>>> wrote:
>>>>
>>>>> One of the questions I have is why one would think that the uplink
>>>>> (polarization) is a problem since you only have the downlink to assess
>>>>> and
>>>>> how would you differentiate between uplink "weakness" from downlink
>>>>> since
>>>>> that is the only thing you hear. In addition, at least for uplink, you
>>>>> could "in principle" very quickly adjust with higher power... and no,
>>>>> I am
>>>>> NOT promoting crocodile behavior (big mouth little ears)
>>>>>
>>>>> Stefan, VE4NSA
>>>>>
>>>>> On Tue, Mar 27, 2018 at 2:26 PM, Burns Fisher <burns@??????.??> wrote:
>>>>>
>>>>> > If you have seen a model or picture of the Fox satellites, you may
>>>>> have
>>>>> > noticed that some of the solar panels seem to be mounted
>>>>> off-center. This
>>>>> > is intentional so that photons that reflect off the shiny side give
>>>>> it a
>>>>> > tiny off-center push that spins the bird to distribute the heat more
>>>>> > evenly. Thus it spins faster the more time it spends in the sun. In
>>>>> > addition, when it crosses the equator, it should flip over (-Z and +Z
>>>>> > reverse sides). This is because of the passive magnetic
>>>>> stabilization.
>>>>> > But I'm guessing that since it is spinning, that causes it to wobble.
>>>>> >
>>>>> > Why 92 seems worse I don't know--I can only assume it has something
>>>>> to do
>>>>> > with the orbit. That graph that Paul posted looks very different
>>>>> from
>>>>> > AO-85, for example.
>>>>> >
>>>>> > Some RF person can correct me, but I believe that the 70cm antenna
>>>>> only
>>>>> > uses the antenna that sticks out one side, while the 2m antenna
>>>>> actually
>>>>> > uses the antennas on both sides. Could that explain why the uplink
>>>>> has
>>>>> > more fading than the downlink? I don't know. Something to think
>>>>> about.
>>>>> >
>>>>> > 73,
>>>>> >
>>>>> > Burns WB1FJ
>>>>> > Fox-1 Flight Software
>>>>> >
>>>>> > On Tue, Mar 27, 2018 at 2:12 PM, Paul Stoetzer <n8hm@????.???>
>>>>> wrote:
>>>>> >
>>>>> > > All of the Fox-1 satellites seem to spin faster or slower
>>>>> depending on
>>>>> > > orbit illumination or other factors.
>>>>> > >
>>>>> > > For example, this is the +Z panel rotation on AO-92 since launch.
>>>>> > >
>>>>> > > https://imgur.com/a/uS8TB
>>>>> > >
>>>>> > > Someone more well-versed in these matters can comment further on
>>>>> what
>>>>> > > causes this, but it is definitely not an indication of the health
>>>>> > > status of the satellite.
>>>>> > >
>>>>> > > 73,
>>>>> > >
>>>>> > > Paul, N8HM
>>>>> > >
>>>>> > > On Tue, Mar 27, 2018 at 1:59 PM, Jean Marc Momple
>>>>> > > <jean.marc.momple@?????.???> wrote:
>>>>> > > > Dear All,
>>>>> > > >
>>>>> > > > I have been experimenting with AO-92 as from its launch. Some
>>>>> > > observations:
>>>>> > > >
>>>>> > > > 1) The fading on this bird seems to be high and quite
>>>>> unpredictable,
>>>>> > > requires a lot of changes of polarization to keep the Rx signal
>>>>> to an
>>>>> > > adequate level.
>>>>> > > >
>>>>> > > > 2) Seems that the fading is both on the U/V and L-mode, more
>>>>> seems to
>>>>> > me
>>>>> > > that the uplink is more affected.
>>>>> > > >
>>>>> > > > 3) Telemetry seems to be quite reliable with FoxTelem in all
>>>>> modes.
>>>>> > > >
>>>>> > > > Today, it was even worse losing the bird many times during the
>>>>> pass, it
>>>>> > > seems that it is degrading quite quickly, hope that this is not
>>>>> the case.
>>>>> > > >
>>>>> > > > Just to share my observation.
>>>>> > > >
>>>>> > > > 73
>>>>> > > >
>>>>> > > >
>>>>> > > > Jean Marc (3B8du)
>>>>> > > >
>>>>> > > >
>>>>> > > > _______________________________________________
>>>>> > > > Sent via AMSAT-BB@?????.???. 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/l
>>>>> istinfo/amsat-bb
>>>>> > > _______________________________________________
>>>>> > > Sent via AMSAT-BB@?????.???. 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/l
>>>>> istinfo/amsat-bb
>>>>> > >
>>>>> > _______________________________________________
>>>>> > Sent via AMSAT-BB@?????.???. 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/l
>>>>> istinfo/amsat-bb
>>>>> >
>>>>> _______________________________________________
>>>>> Sent via AMSAT-BB@?????.???. 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
>>>>>
>>>>
>>>>
>>>
>>
>
------------------------------
Message: 7
Date: Wed, 28 Mar 2018 02:27:48 +0000
From: "Stephen E. Belter" <seb@??????.???>
To: Stefan Wagener <wageners@?????.???>, Sterling Coffey
<kawfey@?????.???>
Cc: Burns Fisher <burns@??????.??>, amsat-bb <amsat-bb@?????.???>,
Paul Stoetzer <n8hm@????.???>
Subject: Re: [amsat-bb] AO-92 fading
Message-ID: <E9EC0BB4-BFDF-493C-A550-096D25700B72@??????.???>
Content-Type: text/plain; charset="utf-8"
Stefan,
You are correct that you only hear the downlink, but...
From personal experience, including operating AO-85 and AO-91 today using a
standard Arrow and an IC-821 (from a campground in EM87), I'm convinced that
I can hear my uplink polarity mismatch.
I first adjust the polarity of my antenna (by twisting my wrist) while
searching for the strongest (maximum quieting) received signal. Then while
pressing the PTT, I tweak the Arrow polarity while going for maximum
quieting while listening to myself.
The best sounding full-duplex signal is typically not at the same polarity
as the best received signal from someone else on the satellite, but I've
been able to get full quieting full-duplex. When operating full-duplex, I
think I'm hearing the results of *both* the uplink and downlink polarity
match.
And that's how I 'differentiate between uplink "weakness" from downlink'
weakness.
73, Steve N9IP
--
Steve Belter, seb@??????.???
?On 3/27/18, 10:06 PM, "AMSAT-BB on behalf of Stefan Wagener"
<amsat-bb-bounces@?????.??? on behalf of wageners@?????.???> wrote:
Hi Sterling,
That would assume you have the ability to switch between linear uplink
polarization (vertical and horizontal) and circular polarisation for
uplink
(right and left) and keep you downlink polarization on the same
optimized path all the time, meaning you know in advance which way the
downlink signal is the best to compensate for any uplink discrepancies.
Good luck :-)
But hanks, good thought!
Stefan, VE4NSA
On Tue, Mar 27, 2018 at 8:47 PM, Sterling Coffey <kawfey@?????.???> wrote:
> If linear polarized, if you can keep your RX/downlink antenna still and
> you can at least hear the satellite, and rotating your TX/uplink antenna
> results in correlated signal level changes on the RX/downlink, then
you've
> isolated it to the uplink polarization variable.
>
> On Tue, Mar 27, 2018 at 8:44 PM, Stefan Wagener <wageners@?????.???>
> wrote:
>
>> Thanks,
>>
>> Again, even in full duplex how do you distinguish between a
non-matching
>> uplink vs non-matching downlink? You only "hear" the downlink!
>>
>> 73, Stefan VE4NSA
>>
>> On Tue, Mar 27, 2018 at 8:38 PM, Sterling Coffey <kawfey@?????.???>
>> wrote:
>>
>>> You can hear your own signal if you have a full duplex (two radio)
>>> setup. However, it's still pretty hard to tell if you use a single
antenna
>>> (arrow, elk, etc) since you're changing the RX polarity while you're
>>> changing the TX polarity too.
>>>
>>> On Tue, Mar 27, 2018 at 7:22 PM, Stefan Wagener <wageners@?????.???>
>>> wrote:
>>>
>>>> One of the questions I have is why one would think that the uplink
>>>> (polarization) is a problem since you only have the downlink to
assess
>>>> and
>>>> how would you differentiate between uplink "weakness" from downlink
>>>> since
>>>> that is the only thing you hear. In addition, at least for uplink,
you
>>>> could "in principle" very quickly adjust with higher power... and
no, I
>>>> am
>>>> NOT promoting crocodile behavior (big mouth little ears)
>>>>
>>>> Stefan, VE4NSA
>>>>
>>>> On Tue, Mar 27, 2018 at 2:26 PM, Burns Fisher <burns@??????.??>
wrote:
>>>>
>>>> > If you have seen a model or picture of the Fox satellites, you may
>>>> have
>>>> > noticed that some of the solar panels seem to be mounted
off-center.
>>>> This
>>>> > is intentional so that photons that reflect off the shiny side give
>>>> it a
>>>> > tiny off-center push that spins the bird to distribute the heat
more
>>>> > evenly. Thus it spins faster the more time it spends in the sun.
In
>>>> > addition, when it crosses the equator, it should flip over (-Z
and +Z
>>>> > reverse sides). This is because of the passive magnetic
>>>> stabilization.
>>>> > But I'm guessing that since it is spinning, that causes it to
wobble.
>>>> >
>>>> > Why 92 seems worse I don't know--I can only assume it has something
>>>> to do
>>>> > with the orbit. That graph that Paul posted looks very different
from
>>>> > AO-85, for example.
>>>> >
>>>> > Some RF person can correct me, but I believe that the 70cm antenna
>>>> only
>>>> > uses the antenna that sticks out one side, while the 2m antenna
>>>> actually
>>>> > uses the antennas on both sides. Could that explain why the uplink
>>>> has
>>>> > more fading than the downlink? I don't know. Something to think
>>>> about.
>>>> >
>>>> > 73,
>>>> >
>>>> > Burns WB1FJ
>>>> > Fox-1 Flight Software
>>>> >
>>>> > On Tue, Mar 27, 2018 at 2:12 PM, Paul Stoetzer <n8hm@????.???>
wrote:
>>>> >
>>>> > > All of the Fox-1 satellites seem to spin faster or slower
depending
>>>> on
>>>> > > orbit illumination or other factors.
>>>> > >
>>>> > > For example, this is the +Z panel rotation on AO-92 since launch.
>>>> > >
>>>> > > https://imgur.com/a/uS8TB
>>>> > >
>>>> > > Someone more well-versed in these matters can comment further on
>>>> what
>>>> > > causes this, but it is definitely not an indication of the health
>>>> > > status of the satellite.
>>>> > >
>>>> > > 73,
>>>> > >
>>>> > > Paul, N8HM
>>>> > >
>>>> > > On Tue, Mar 27, 2018 at 1:59 PM, Jean Marc Momple
>>>> > > <jean.marc.momple@?????.???> wrote:
>>>> > > > Dear All,
>>>> > > >
>>>> > > > I have been experimenting with AO-92 as from its launch. Some
>>>> > > observations:
>>>> > > >
>>>> > > > 1) The fading on this bird seems to be high and quite
>>>> unpredictable,
>>>> > > requires a lot of changes of polarization to keep the Rx
signal to
>>>> an
>>>> > > adequate level.
>>>> > > >
>>>> > > > 2) Seems that the fading is both on the U/V and L-mode, more
>>>> seems to
>>>> > me
>>>> > > that the uplink is more affected.
>>>> > > >
>>>> > > > 3) Telemetry seems to be quite reliable with FoxTelem in all
>>>> modes.
>>>> > > >
>>>> > > > Today, it was even worse losing the bird many times during the
>>>> pass, it
>>>> > > seems that it is degrading quite quickly, hope that this is not
the
>>>> case.
>>>> > > >
>>>> > > > Just to share my observation.
>>>> > > >
>>>> > > > 73
>>>> > > >
>>>> > > >
>>>> > > > Jean Marc (3B8du)
>>>> > > >
>>>> > > >
>>>> > > > _______________________________________________
>>>> > > > Sent via AMSAT-BB@?????.???. 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/l
>>>> istinfo/amsat-bb
>>>> > > _______________________________________________
>>>> > > Sent via AMSAT-BB@?????.???. 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/l
>>>> istinfo/amsat-bb
>>>> > >
>>>> > _______________________________________________
>>>> > Sent via AMSAT-BB@?????.???. 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 AMSAT-BB@?????.???. 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 AMSAT-BB@?????.???. 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
------------------------------
Subject: Digest Footer
_______________________________________________
Sent via amsat-bb@?????.???.
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 member? Join now to support the amateur satellite program!
http://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
End of AMSAT-BB Digest, Vol 13, Issue 118
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