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CX2SA > SATDIG 24.03.16 20:36l 974 Lines 38945 Bytes #999 (0) @ WW
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To : SATDIG@WW
Today's Topics:
1. Re: Station decisions re. upcoming Geosync bird (Joe)
2. Re: Ceuta & Melilla and Gibraltar this summer (Dani EA4GPZ)
3. Re: Optical shaft encoders (Steven Kalmar)
4. Re: Station decisions re. upcoming Geosync bird (Jim Walls)
5. Re: Station decisions re. upcoming Geosync bird
(Patrick STODDARD (WD9EWK/VA7EWK))
6. Re: Station decisions re. upcoming Geosync bird (Goody K3NG)
7. FO-29 inteference - help needed @ 1914z (Kevin M)
8. FO-29 inteference - help needed @ 1914z (Kevin M)
9. GEO sats and the future (Jeff Moore)
----------------------------------------------------------------------
Message: 1
Date: Thu, 24 Mar 2016 07:46:14 -0500
From: Joe <nss@xxx.xxx>
To: Paul Stoetzer <n8hm@xxxx.xxx>
Cc: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: Re: [amsat-bb] Station decisions re. upcoming Geosync bird
Message-ID: <56F3E196.9040909@xxx.xxx>
Content-Type: text/plain; charset=utf-8; format=flowed
That isn't too bad.
It would be a killer when running CW and monitoring like a sidetone tho!
he he he.
Joe WB9SBD
Sig
The Original Rolling Ball Clock
Idle Tyme
Idle-Tyme.com
http://www.idle-tyme.com
On 3/24/2016 7:35 AM, Paul Stoetzer wrote:
> 240-280 ms
>
> 73,
>
> Paul, N8HM
>
> On Thu, Mar 24, 2016 at 8:31 AM, Joe <nss@xxx.xxx> wrote:
>> Full Duplex on a Geo Bird,,,,?
>>
>> What is the delay lag time on such a distance?
>>
>> Joe WB9SBD
>> Sig
>> The Original Rolling Ball Clock
>> Idle Tyme
>> Idle-Tyme.com
>> http://www.idle-tyme.com
>>
>> On 3/23/2016 11:17 PM, John Toscano wrote:
>>> Details on the satellite are still quite sensitive, but details on ground
>>> station requirements are much more readily discussed due to the lack of
>>> ITAR restrictions there.
>>>
>>> One approach to the ground station would be to add a 5G and a 10G
>>> transverter to your existing radios, using them for IF radios. Though many
>>> 5G and 10G transverters use a 144 MHz IF, some are available with a 432
>>> MHz
>>> IF. Getting one of the two transverters with a 432 MHz IF and one with a
>>> 144 MHz IF would probably facilitate full-duplex operation, unless you
>>> have
>>> two 144 MHz IF radios available.
>>>
>>> This sort of approach might be preferred by an operator who plans to add
>>> those two bands to BOTH terrestrial and satellite operation. But if you
>>> were adding these two bands for satellite use only, there is significant
>>> opportunity for financial savings. You only need a 5G transmitting
>>> converter and a 10G receiving converter. On the receiving end, a modest
>>> satellite dish and an inexpensive LNBF designed for for satellite TV will
>>> convert the satellite downlink to a signal somewhere near 700 MHz, which
>>> is
>>> easily within the RF range of many software-defined radios. The ground
>>> station team has been hoping that an under-$20 satellite TV PLL-LNBF
>>> coupled with an inexpensive RTL-SDR dongle MIGHT suffice for the heart of
>>> the 10G receiver. For the uplink, it is possible that a $300-ish HackRF
>>> One
>>> SDR (which can transmit at up to 6 GHz), coupled with appropriate
>>> filtering
>>> and a suitable power amplifier might form the heart of an inexpensive 5G
>>> transmitter. The ground station team is looking at other, more expensive
>>> solutions, as well, and we can't yet promise that the rock-bottom-price
>>> solutions will work until they have been well-tested.
>>>
>>> In any event, digital modes are going to be the order of the day, so if
>>> you
>>> are using a pair of all-mode radios as IF's, they will need to support a
>>> digital interface to a computer. That's one of the reasons why we are so
>>> excited about the possibilities of SDR to get us from RF to digital data
>>> and back at affordable prices.
>>>
>>> \I hope that helps at least a little bit.
>>>
>>> John Toscano, W0JT/5
>>>
>>> On Wed, Mar 23, 2016 at 7:44 PM, Peter Klein <pklein@xxxxxxxxx.xxx> wrote:
>>>
>>>> I've been casually following the discussion of the upcoming
>>>> geosynchronous
>>>> satellite. I currently have a Mode B , J and A analog setup that I've
>>>> used
>>>> on Oscar 10 and 13, and on some LEOs. This includes crossed Yagis on 2m
>>>> and
>>>> 70cm, and an all-mode radio for those bands. LEOs and flying mailboxes
>>>> no
>>>> longer interest me, so in recent years that setup has only been used for
>>>> occasional terrestrial VHF SSB/CW, plus local repeater activity.
>>>>
>>>> I will need to make some decisions on my general station setup soon.
>>>> Antenna space is limited, and I want to take the possibility of the
>>>> geosync
>>>> bird into consideration. From what I've read and seen on video, the
>>>> uplinks and downlinks to the satellite will be microwave. The satellite
>>>> track will make a figure-8 pattern in the sky, but I don't know how large
>>>> that pattern will be at my location. My 144 and 440 MHz antennas will not
>>>> be compatible with the new bird. But will the 144/440 radios be useful,
>>>> perhaps as an IF after the digital gymnastics happen in a converter?
>>>>
>>>> So, my questions:
>>>>
>>>> - Are any "dummy" Keplarian elements available for the geosynch bird's
>>>> planned (or likely) orbit? That would let me do some "what-iffing."
>>>> - If the above are not available, could someone tell me the approximate
>>>> range of azimuth and elevation I might expect from CN87 (Seattle area)?
>>>> - What is the physical size of the required dishes?
>>>> - Will the radio for the new bird be self-contained, or require another
>>>> radio as an IF? If the latter, what frequency band or bands are being
>>>> contemplated for the IF?
>>>>
>>>> If I've asked things that are too sensitive to discuss right now, let me
>>>> know and I'll shut up. :-)
>>>>
>>>> 73,
>>>> --Peter, KD7MW
>>>>
>>>> _______________________________________________
>>>> Sent via AMSAT-BB@xxxxx.xxx. 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@xxxxx.xxx. 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@xxxxx.xxx. 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: 2
Date: Thu, 24 Mar 2016 13:59:23 +0100
From: Dani EA4GPZ <daniel@xxxxxxxx.xxx>
To: amsat-bb@xxxxx.xxx
Subject: Re: [amsat-bb] Ceuta & Melilla and Gibraltar this summer
Message-ID: <56F3E4AB.7040700@xxxxxxxx.xxx>
Content-Type: text/plain; charset=windows-1252
El 24/03/16 a las 13:08, M5AKA escribi?:
> The IARU Region 1 Treasurer Eva Thiemann HB9FPM visited Gibraltar last
August. She noted that:
>
> "Gibraltar is not part of CEPT and the authorities do not issue reciprocal
licences for HF operation. But for some time it is possible to get a licence
for operating on 6 and 2 m." - apparently not 70 cm.
>
> The Gibraltar Amateur Radio Society has some visitor information on their
website at
> http://www.gibradio.net/visiting.htm
>
> There are still many countries in the world where reciprocal operating is
either not permitted or is difficult to obtain.
Hi Trevor,
According to this document:
http://www.gra.gi/download/889/401cfg.pdf
operation in 70cm is also possible with the reciprocal licence.
The problem here seems to be that the authorities in Gibraltar won't
accept a Spanish licence as a valid document to grant a reciprocal licence.
73,
Dani EA4GPZ.
------------------------------
Message: 3
Date: Thu, 24 Mar 2016 09:43:41 -0400
From: Steven Kalmar <pista01@xxxxx.xxx>
To: John Toscano <tosca005@xxx.xxx>
Cc: amsat bb <amsat-bb@xxxxx.xxx>
Subject: Re: [amsat-bb] Optical shaft encoders
Message-ID:
<CAEpGj_N-iAcOZ8+jiSDhxJy_FvDQanUjmqafRjuOFfnNg1DUiQ@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
John,
I'm testing this board with my custom rotators and controller. The board
has been working quite well, with consistent reading for both az and el.
The az readings are even accurate when the el is at 90 degrees.
That said, I won't be using it as a primary position sensor. Optical
encoders with sufficient resolution are still superior. I haven't tested
this board in the presence of RF, so I'm not sure what it will do on
transmit. The board also can't tell you if the rotators are pointing at
360 degrees or 0. A POT, or something similar, is still needed to
determine that. The i2c bus needs to be as short as possible, so whatever
is reading it needs to be mounted on the rotators. Positioning the
controller with the rotators will also improve the reliability of the
optical encoders. This board works well for calibrating the rotator to
magnetic north and zeroing the el, as well as validating the az & el
positions reported by the optical encoders. How well the validation will
work on transmit is yet to be determined.
If all you want to do is read the position outside the controller circuit,
then I would think it would work quite well connected to an Arduino mounted
on the rotator. An ethernet shield would allow for a simple web page that
could display the rotator's position. Reading the values off the board is
quick and doesn't require very much resources. Calibration is the main
issue with these types of sensors. It's much easier to deal with on this
board. The on-board micro helps a great deal. The calibration data is
lost when the board powers up. Until it is calibrated, the values are
useless. Once calibrated, previous saved calibration values can be passed
to the board when it powers up. The initial calibration does call for
specific movements outside the range possible by just mounting it to the
rotator and moving it around. The initial calibration would need to be
done close to the actual mounted position on the rotator. Once the rotator
and sensor are in their final positions and the rotator az and el moved
around a bit, the on-board micro will update it's calibration values from
the initial calibration. These final calibration values would be the
values to save and re-apply on power up. Since the on-board micro
continues to update the calibration, it might be a good idea to update the
saved values periodically.
Steve
KD8QWT
On Wed, Mar 23, 2016 at 5:58 PM, John Toscano <tosca005@xxx.xxx> wrote:
> Bob et. al.:
>
> Would something like this:
> https://www.adafruit.com/products/2472
>
> ...be useful for the purpose of determining absolute position without
> relying on mechanical linkages of gears, belts, pulses, potentiometers,
> etc.? It uses 3-axis magnetometers, 3-axis gyros, and 3-axis
> accelerometers, and a Cortex M0 ARM to do all the hard computations that
> combine the three types of data into a viable position indication. It is
> inexpensive enough that I will probably install one when I finally get
> around to raising a tower at my new QTH, and using it only for readouts at
> first. I have been using and will resume using Yaesu rotators when the
> tower goes up, so no urgent need to add safety limit switches etc. In many
> years of operation at my prior QTH, the rotator never got "confused" about
> its position except when somebody put tension on the cable plugged into the
> back of the control box and loosened some of the connections between plug
> and socket. I do realize that even the G1000SDX model I was/will be using
> is not hefty enough for some applications, but again it served me well for
> many years in spite of temperature swings from -40F to +105F. (Yeah, it
> turned a bit slower at the begining of a contest when the temp was -40F and
> the wind chill was -60F. OK, wind chill doesn't apply to inanimate objects,
> but -40F actual is pretty darned cold. Plus the ice and snow added on
> didn't help.) :-)
>
> 73 de W0JT/5
> EN34js -> EL09vu
>
> On Tue, Mar 22, 2016 at 8:53 PM, Robert McGwier <rwmcgwier@xxxxx.xxx>
> wrote:
>
> > This is an awesome conversation and we are extremely grateful.
> >
> > Zach is trying to build a robust repeatable super ground station.
> >
> > Bob
> > On Mar 18, 2016 6:30 AM, "Daniel Cussen" <zg3410@xxxxx.xxx> wrote:
> >
> > > >for those with Alfa Radio HR model rotators, maybe you have
> same/similar
> > > issues?
> > >
> > > I do not have a HR model, but I do have a similar system and we are
> > > seeing similar problems.
> > >
> > > First off there is no end stop safety switches. This means if the
> > > control box becomes confused it can damage coax cables and move
> > > elevation to positions to damage antennas etc.
> > >
> > > Second, there is no absolute position sent, meaning if it gets
> > > confused it cannot reset itself as only the amount of movement is
> > > sent, not the actual current position. Over time this means errors
> > > accumulate and grow.
> > >
> > > The basic Yaesu G5500 has both safety protections meaning it is
> > > unlikely a confused control box will result in damaged antennas or
> > > coax.
> > >
> > > >So first off, Bob is basically asking if anyone has built a custom
> > > optical shaft encoder to >replace the magnetic hall effect sensors in
> the
> > > High Resolution Big-Ras rotators. >Machining, circuit design,
> > > performance.....?
> > >
> > > I do not know, however I have nearly added safety switches to a
> > > similar model to turn off the motor to protect the coax cables. This
> > > is also very important if the relays stick in the control box.
> > >
> > > Others have removed or replaced position sensors with more accurate
> > > absolute positions sensors. In particular the HH-12 is used by a lot
> > > of large EME stations as it is both accurate, cheap and absolute
> > > position. If you connect it using a rubber hose it will protect itself
> > > from damage if you try turn it too much.
> > >
> > > http://www.vk5dj.com/hh-12.html
> > > Mounting it to the Big-Raz is unknown, but here is a similar project:
> > > http://e-kutz.eu/seite10.html
> > > Here is a complete controller with two sensors:
> > > http://f1frv.free.fr/main3o_AZ_EL_Display.html
> > >
> > > >The noise voltage was 1 or 2 volts peak to peak when measuring the
> lines
> > > with an o->scope.
> > >
> > > This is not good.
> > >
> > > > The shields of the cables are connected together at the connector on
> > the
> > > rotator (8 pin >MIC connector) and at the connector on the MD-01
> control
> > > box. The shield is also >jumpered to a good station ground at the
> > control
> > > box.
> > >
> > > To reduce noise the recommendation it to only connect the shield AT
> > > ONE END, and not both ends. Normally only at the shack end. I think
> > > this prevents ground loops.
> > >
> > > >So that's about it in a 'nutshell.'
> > >
> > > So in my case we have a similar sensor. All the HAMTV ground stations
> > > in Europe (6) are using Prosistel Az/El with uses hall magnetic
> > > sensors with thousands of pulses per second. We too are seeing
> > > positions change with the motor stop, so much so thousands of pulses
> > > must be read while stopped.
> > >
> > > The solutions we have used so far:
> > > 1) Multiple screened cables as you suggest grounded at one end
> > > 2) Adding filters to the motor wiring to reduce motor noise/cross talk
> > > 3) I experimented with stepping up rotation feedback from 0/5V to 0/20V
> > > 4) I am working on a replacement control box, where we can modify the
> > code
> > > 5) I am adding safety switches to protect the coax.
> > >
> > > The real solution would be for the manufacturer to use absolute
> > > position feedback. There is complete controllers available, if you can
> > > manage to connect their sensors to your existing system using
> > > belts/gears/cogs etc.
> > >
> > > Another option I think you should consider is using your own control
> > > box. We found that the Prosistel supplied control box was flawed in
> > > some ways. The open source control box is already designed to take
> > > pulse inputs, and seems to work with thousands of pulses per second.
> > > You can even just hook the inputs in parallel to see if the problem is
> > > the control box or the sensor outputs. All you need is an arduino
> > > (mega preferably) and the correct version of the code. It will display
> > > a second opinion of the position, so you can determine if the control
> > > box has issues too. We found our control box misses some pulses, we
> > > think it is busy updating the LCD or talking to the computer and
> > > misses pulses.
> > >
> > > Other features of this is a master/slave option, meaning the
> > > controller can be mounted at the antenna, meaning only short cable
> > > runs to the position sensor.
> > >
> > > http://blog.radioartisan.com/yaesu-rotator-computer-serial-interface/
> > >
> > > In the long term absolute position sensors combined with safety
> > > switches are the only real solution. For HF even a bog standard
> > > potentiometer would probably work better. Some suppliers use 3 or 10
> > > turn potentiometers to allow 360 degrees or 1.5 turns rotation.
> > > _______________________________________________
> > > Sent via AMSAT-BB@xxxxx.xxx. 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@xxxxx.xxx. 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@xxxxx.xxx. 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
>
--
"In a time of universal deceit, telling the truth becomes an act of
rebellion."
--George Orwell
------------------------------
Message: 4
Date: Thu, 24 Mar 2016 07:25:41 -0700
From: "Jim Walls" <jim@xxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Subject: Re: [amsat-bb] Station decisions re. upcoming Geosync bird
Message-ID: <81b76c4547754d1aa337fb39bdf8d98a@xxxxx.xxx>
Content-Type: text/plain; charset="us-ascii"
Sure. Remember that AO-40 at apogee was WAY beyond the Clark belt. Took a
little bit of getting used to, but was not a real problem.
Jim - K6CCC
----------------------------------------
From: "Joe" <nss@xxx.xxx>
Sent: Thursday, March 24, 2016 5:32 AM
To: amsat-bb@xxxxx.xxx
Subject: Re: [amsat-bb] Station decisions re. upcoming Geosync bird
Full Duplex on a Geo Bird,,,,?
What is the delay lag time on such a distance?
Joe WB9SBD
Sig
The Original Rolling Ball Clock
Idle Tyme
Idle-Tyme.com
http://www.idle-tyme.com
On 3/23/2016 11:17 PM, John Toscano wrote:
> Details on the satellite are still quite sensitive, but details on
ground
> station requirements are much more readily discussed due to the lack of
> ITAR restrictions there.
>
> One approach to the ground station would be to add a 5G and a 10G
> transverter to your existing radios, using them for IF radios. Though
many
> 5G and 10G transverters use a 144 MHz IF, some are available with a 432
MHz
> IF. Getting one of the two transverters with a 432 MHz IF and one with a
> 144 MHz IF would probably facilitate full-duplex operation, unless you
have
> two 144 MHz IF radios available.
>
> This sort of approach might be preferred by an operator who plans to add
> those two bands to BOTH terrestrial and satellite operation. But if you
> were adding these two bands for satellite use only, there is significant
> opportunity for financial savings. You only need a 5G transmitting
> converter and a 10G receiving converter. On the receiving end, a modest
> satellite dish and an inexpensive LNBF designed for for satellite TV
will
> convert the satellite downlink to a signal somewhere near 700 MHz, which
is
> easily within the RF range of many software-defined radios. The ground
> station team has been hoping that an under-$20 satellite TV PLL-LNBF
> coupled with an inexpensive RTL-SDR dongle MIGHT suffice for the heart
of
> the 10G receiver. For the uplink, it is possible that a $300-ish HackRF
One
> SDR (which can transmit at up to 6 GHz), coupled with appropriate
filtering
> and a suitable power amplifier might form the heart of an inexpensive 5G
> transmitter. The ground station team is looking at other, more expensive
> solutions, as well, and we can't yet promise that the rock-bottom-price
> solutions will work until they have been well-tested.
>
> In any event, digital modes are going to be the order of the day, so if
you
> are using a pair of all-mode radios as IF's, they will need to support a
> digital interface to a computer. That's one of the reasons why we are so
> excited about the possibilities of SDR to get us from RF to digital data
> and back at affordable prices.
>
> \I hope that helps at least a little bit.
>
> John Toscano, W0JT/5
>
> On Wed, Mar 23, 2016 at 7:44 PM, Peter Klein <pklein@xxxxxxxxx.xxx>
wrote:
>
>> I've been casually following the discussion of the upcoming
geosynchronous
>> satellite. I currently have a Mode B , J and A analog setup that I've
used
>> on Oscar 10 and 13, and on some LEOs. This includes crossed Yagis on 2m
and
>> 70cm, and an all-mode radio for those bands. LEOs and flying mailboxes
no
>> longer interest me, so in recent years that setup has only been used
for
>> occasional terrestrial VHF SSB/CW, plus local repeater activity.
>>
>> I will need to make some decisions on my general station setup soon.
>> Antenna space is limited, and I want to take the possibility of the
geosync
>> bird into consideration. From what I've read and seen on video, the
>> uplinks and downlinks to the satellite will be microwave. The satellite
>> track will make a figure-8 pattern in the sky, but I don't know how
large
>> that pattern will be at my location. My 144 and 440 MHz antennas will
not
>> be compatible with the new bird. But will the 144/440 radios be useful,
>> perhaps as an IF after the digital gymnastics happen in a converter?
>>
>> So, my questions:
>>
>> - Are any "dummy" Keplarian elements available for the geosynch bird's
>> planned (or likely) orbit? That would let me do some "what-iffing."
>> - If the above are not available, could someone tell me the approximate
>> range of azimuth and elevation I might expect from CN87 (Seattle area)?
>> - What is the physical size of the required dishes?
>> - Will the radio for the new bird be self-contained, or require another
>> radio as an IF? If the latter, what frequency band or bands are being
>> contemplated for the IF?
>>
>> If I've asked things that are too sensitive to discuss right now, let
me
>> know and I'll shut up. :-)
>>
>> 73,
>> --Peter, KD7MW
>>
>> _______________________________________________
>> Sent via AMSAT-BB@xxxxx.xxx. 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@xxxxx.xxx. 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@xxxxx.xxx. 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: 5
Date: Thu, 24 Mar 2016 15:40:09 +0000
From: "Patrick STODDARD (WD9EWK/VA7EWK)" <amsat-bb@xxxxxx.xxx>
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: Re: [amsat-bb] Station decisions re. upcoming Geosync bird
Message-ID:
<CAN6TEUf+btxipoPsF3z0cZmUTPy40Zv+9_Zb+WT7wxfpXuwiRA@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
Hi!
One way to get acclimated to that sort of delay, before we have any
of the higher-orbit satellites available, could be to work the current
satellites using an SDR receiver for the downlink. Even the faster
computers introduce some delay in hearing the downlinks, and the
smaller/cheaper Windows tablets I use certainly do that. It takes
some practice to line yourself up on the transponders, knowing that
you won't hear yourself as quickly with an SDR receiver as you would
with a "real" radio hearing the downlink.
With practice, working the transponders using an SDR receiver has
been fun. I get the benefits of SDR like seeing the full transponder,
I can make a recording of everything I'm receiving in my software, and
being able to see and hear myself with the software really helps in
getting lined up (and staying lined up throughout a pass). And for
some of the satellites, I can then take the recording and play it
into software to extract telemetry that I was receiving during the
pass.
This means the delays using an SDR receiver with any of these other
satellites in higher orbits will be longer, but - again, with practice -
it will be doable. I enjoy working the satellites we currently have,
and look forward to these projects being launched and having to
get the necessary equipment to work them. :-)
73!
Patrick WD9EWK/VA7EWK
http://www.wd9ewk.net/
Twitter: @xxxxxx
On Thu, Mar 24, 2016 at 2:25 PM, Jim Walls <jim@xxxxx.xxx> wrote:
> Sure. Remember that AO-40 at apogee was WAY beyond the Clark b
> ??
> elt. Took a
> little bit of getting used to, but was not a real problem.
>
------------------------------
Message: 6
Date: Thu, 24 Mar 2016 13:26:52 -0400
From: Goody K3NG <goody.k3ng@xxxxx.xxx>
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: Re: [amsat-bb] Station decisions re. upcoming Geosync bird
Message-ID:
<CAK2SEys6mSR364yOjTWc4fspoEcTvk3JJqiuH34w=G_EbnKMig@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
I'm working on a CW keyer that uses quantum mechanics to send the code
before you actually send it, thereby negating the propagation delay. :-)
On Thu, Mar 24, 2016 at 8:46 AM, Joe <nss@xxx.xxx> wrote:
> That isn't too bad.
> It would be a killer when running CW and monitoring like a sidetone tho!
> he he he.
>
> Joe WB9SBD
> Sig
> The Original Rolling Ball Clock
> Idle Tyme
> Idle-Tyme.com
> http://www.idle-tyme.com
> On 3/24/2016 7:35 AM, Paul Stoetzer wrote:
>
>> 240-280 ms
>>
>> 73,
>>
>> Paul, N8HM
>>
>> On Thu, Mar 24, 2016 at 8:31 AM, Joe <nss@xxx.xxx> wrote:
>>
>>> Full Duplex on a Geo Bird,,,,?
>>>
>>> What is the delay lag time on such a distance?
>>>
>>> Joe WB9SBD
>>> Sig
>>> The Original Rolling Ball Clock
>>> Idle Tyme
>>> Idle-Tyme.com
>>> http://www.idle-tyme.com
>>>
>>> On 3/23/2016 11:17 PM, John Toscano wrote:
>>>
>>>> Details on the satellite are still quite sensitive, but details on
>>>> ground
>>>> station requirements are much more readily discussed due to the lack of
>>>> ITAR restrictions there.
>>>>
>>>> One approach to the ground station would be to add a 5G and a 10G
>>>> transverter to your existing radios, using them for IF radios. Though
>>>> many
>>>> 5G and 10G transverters use a 144 MHz IF, some are available with a 432
>>>> MHz
>>>> IF. Getting one of the two transverters with a 432 MHz IF and one with a
>>>> 144 MHz IF would probably facilitate full-duplex operation, unless you
>>>> have
>>>> two 144 MHz IF radios available.
>>>>
>>>> This sort of approach might be preferred by an operator who plans to add
>>>> those two bands to BOTH terrestrial and satellite operation. But if you
>>>> were adding these two bands for satellite use only, there is significant
>>>> opportunity for financial savings. You only need a 5G transmitting
>>>> converter and a 10G receiving converter. On the receiving end, a modest
>>>> satellite dish and an inexpensive LNBF designed for for satellite TV
>>>> will
>>>> convert the satellite downlink to a signal somewhere near 700 MHz, which
>>>> is
>>>> easily within the RF range of many software-defined radios. The ground
>>>> station team has been hoping that an under-$20 satellite TV PLL-LNBF
>>>> coupled with an inexpensive RTL-SDR dongle MIGHT suffice for the heart
>>>> of
>>>> the 10G receiver. For the uplink, it is possible that a $300-ish HackRF
>>>> One
>>>> SDR (which can transmit at up to 6 GHz), coupled with appropriate
>>>> filtering
>>>> and a suitable power amplifier might form the heart of an inexpensive 5G
>>>> transmitter. The ground station team is looking at other, more expensive
>>>> solutions, as well, and we can't yet promise that the rock-bottom-price
>>>> solutions will work until they have been well-tested.
>>>>
>>>> In any event, digital modes are going to be the order of the day, so if
>>>> you
>>>> are using a pair of all-mode radios as IF's, they will need to support a
>>>> digital interface to a computer. That's one of the reasons why we are so
>>>> excited about the possibilities of SDR to get us from RF to digital data
>>>> and back at affordable prices.
>>>>
>>>> \I hope that helps at least a little bit.
>>>>
>>>> John Toscano, W0JT/5
>>>>
>>>> On Wed, Mar 23, 2016 at 7:44 PM, Peter Klein <pklein@xxxxxxxxx.xxx>
>>>> wrote:
>>>>
>>>> I've been casually following the discussion of the upcoming
>>>>> geosynchronous
>>>>> satellite. I currently have a Mode B , J and A analog setup that I've
>>>>> used
>>>>> on Oscar 10 and 13, and on some LEOs. This includes crossed Yagis on 2m
>>>>> and
>>>>> 70cm, and an all-mode radio for those bands. LEOs and flying mailboxes
>>>>> no
>>>>> longer interest me, so in recent years that setup has only been used
>>>>> for
>>>>> occasional terrestrial VHF SSB/CW, plus local repeater activity.
>>>>>
>>>>> I will need to make some decisions on my general station setup soon.
>>>>> Antenna space is limited, and I want to take the possibility of the
>>>>> geosync
>>>>> bird into consideration. From what I've read and seen on video, the
>>>>> uplinks and downlinks to the satellite will be microwave. The
>>>>> satellite
>>>>> track will make a figure-8 pattern in the sky, but I don't know how
>>>>> large
>>>>> that pattern will be at my location. My 144 and 440 MHz antennas will
>>>>> not
>>>>> be compatible with the new bird. But will the 144/440 radios be
>>>>> useful,
>>>>> perhaps as an IF after the digital gymnastics happen in a converter?
>>>>>
>>>>> So, my questions:
>>>>>
>>>>> - Are any "dummy" Keplarian elements available for the geosynch bird's
>>>>> planned (or likely) orbit? That would let me do some "what-iffing."
>>>>> - If the above are not available, could someone tell me the approximate
>>>>> range of azimuth and elevation I might expect from CN87 (Seattle area)?
>>>>> - What is the physical size of the required dishes?
>>>>> - Will the radio for the new bird be self-contained, or require another
>>>>> radio as an IF? If the latter, what frequency band or bands are being
>>>>> contemplated for the IF?
>>>>>
>>>>> If I've asked things that are too sensitive to discuss right now, let
>>>>> me
>>>>> know and I'll shut up. :-)
>>>>>
>>>>> 73,
>>>>> --Peter, KD7MW
>>>>>
>>>>> _______________________________________________
>>>>> Sent via AMSAT-BB@xxxxx.xxx. 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@xxxxx.xxx. 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@xxxxx.xxx. 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@xxxxx.xxx. 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: Thu, 24 Mar 2016 18:09:20 +0000 (UTC)
From: Kevin M <n4ufo@xxxxx.xxx>
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] FO-29 inteference - help needed @ 1914z
Message-ID:
<1915823883.4771919.1458842960089.JavaMail.yahoo@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
Hello all, I just heard the FM interference in the upper part of the FO-29
passband. I wasn't expecting it and did not have a recorder running. If
anyone that can record the pass is free, can you please try to capture as
much audio as possible. I copied a partial callsign from a CW ID that pegs
the possible source as being somehow involved with an internet linked UHF
repeater in the Houston area. This next FO-29 pass is going DIRECTLY OVER
Houston @ 1914Z? If there is any chance of grabbing a for sure
identification (CW ID) that would be great. Working also with someone in
Houston to figure things out.
thanks & 73!? kevin n4UFO
------------------------------
Message: 8
Date: Thu, 24 Mar 2016 18:20:57 +0000 (UTC)
From: Kevin M <n4ufo@xxxxx.xxx>
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] FO-29 inteference - help needed @ 1914z
Message-ID:
<1277193965.4868530.1458843657077.JavaMail.yahoo@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
UPDATE:? Boy that was quick... just got a call from the fellow I am working
with in Houston. He has found the actual signal ON THE AIR on 145.930 MHz in
the Houston area and it is currently transmitting with the content coming
from the very UHF repeater I identified. Coincidentally he is the person
responsible for that very same repeater. SO, the interfering signal has been
generally located, now it is a matter of narrowing it down and figuring out
where it is coming from. Possibly a ham has his dual band radio set to cross
band repeat, etc.
Thanks everyone... I guess there is a line on it and hopefully it will be
found.? 73, Kevin N4UFO
------------------------------
Message: 9
Date: Thu, 24 Mar 2016 11:30:50 -0700
From: Jeff Moore <tnetcenter@xxxxx.xxx>
To: Amsat BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] GEO sats and the future
Message-ID:
<CALx_moRm1n6OBnerVyWyuPBuWd1m0bDeg79cqj7PNRMdWcP1bQ@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
I have been in the hobby for over 12 years now and I've played around a bit
with working the sats, but I haven't been following the geosynchronous
satellite activity very closely since I've seen how difficult it is to get
launches of any kind.
Now that it appears that we are going to get to launch a satellite into
geosynchronous orbit, I'm curious what the future may hold for that
particular activity. For example, I think it's fantastic that we will soon
have a sat in geo orbit, but I'm curious what if any plans are there to
potentially put up 2 or 3 more geo sats with full time linking between
them? That has the potential to give the ham radio community global
communications via satellite.
Any thoughts or news on that front?? Or am I just not informed enough on
existing plans?
Thanks and 7 3,
Jeff Moore -- KE7ACY
Bend, Oregon
------------------------------
Subject: Digest Footer
_______________________________________________
Sent via amsat-bb@xxxxx.xxx.
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 11, Issue 92
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