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CX2SA > SATDIG 23.10.14 14:11l 284 Lines 9826 Bytes #999 (0) @ WW
BID : AMSATBB9363
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Subj: AMSAT-BB-digest V9 363
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Sent: 141023/1202Z @:CX2SA.SAL.URY.SOAM #:11699 [Salto] FBB7.00e $:AMSATBB9363
From: CX2SA@CX2SA.SAL.URY.SOAM
To : SATDIG@WW
Today's Topics:
1. Re: Going Digital Someday (M5AKA)
2. Re: Going Digital Someday (Paul Stoetzer)
3. Re: Going Digital Someday (JoAnne K9JKM)
4. AMSAT Journal Sep/OCT 2014 (Rick Walter)
5. Saturday Oct-25 14hs GMT Betty V Balloon Launch (Amsat Argentina)
6. LituanicSAT-2 + 4M lunar payload (M5AKA)
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Message: 1
Date: Wed, 22 Oct 2014 12:07:26 +0000 (UTC)
From: M5AKA <m5aka@xxxxx.xx.xx>
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: Re: [amsat-bb] Going Digital Someday
Message-ID:
<1903531867.102253.1413979646892.JavaMail.yahoo@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
> Analog SSB and CW modulation in a 3U to 6U cubesat may not be practical at
HEO
If that were true then it follows that the modulation currently used with
Codec2 Digital Voice is not practical for HEO either.
Codec2 Digital Voice may use just over half the bandwidth of SSB but it is
100% duty cycle which which will increase the power drain on the satellite.
Current Codec2 DV does not work at low signal to noise ratios - higher power
would be required on the downlink to achieve satisfactory performance.
That said, it may well be that a modulation scheme can be developed that can
deliver a reasonable data rate to support speech, say 1600-2400 bps, at a
low S/N (<10 dB) while not being critical on tuning.
73 Trevor M5AKA
------------------------------
Message: 2
Date: Wed, 22 Oct 2014 08:34:54 -0400
From: Paul Stoetzer <n8hm@xxxx.xxx>
To: Stefan Wagener <wageners@xxxxx.xxx>
Cc: AMSAT BB <amsat-bb@xxxxx.xxx>
Subject: Re: [amsat-bb] Going Digital Someday
Message-ID:
<CABzOSOqzp0MPcT=8sX+5LSof6-=j5Qgo7xp_yXsqoXS+mt8vWw@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
Stefan & JoAnne,
NX9G and W0DHB attempted a FreeDV QSO via FO-29 about a year ago, but
I believe they were not able to compensate for Doppler well enough to
make it work.
73,
Paul, N8HM
On Tue, Oct 21, 2014 at 9:08 PM, Stefan Wagener <wageners@xxxxx.xxx> wrote:
> Point well made, JoAnne.
>
> Now, can AMSAT official support this mode, maybe help/encourage the
> developers and start to implement it (testing) on for example FO-29? What
> about a digital mode for the FM satellites? One of the big frustration I
> have is to decide which one of the digital modes to pick. What is beautiful
> about this hobby is the diversification which now also becomes the "curse"
> with promotion and competition of various commercial and open source
> modes/codecs. Maybe we can help and focus on one "system" for amateur
> satellite use and get it used/implemented.
>
> Food for thought,
>
> Stefan, VE4NSA
>
> On Tue, Oct 21, 2014 at 4:10 PM, JoAnne Maenpaa <k9jkm@xxxxxxx.xxx> wrote:
>
>> During the Symposium in Baltimore last week there was a discussion that I
>> found quite interesting. Billed as a proposal for fairly long-term, future
>> AMSAT HEO possibilities, this blue-sky proposal offers projects that will
>> be
>> fun for myself (and maybe yourself) to learn what's next ... or could be
>> next ...
>>
>> It seems the cubesat form factor is here to stay for practical launch
>> opportunities available to us ... (please don't ask for getting a phase
>> III-B form factor in this thread!) Wiser people than myself have assured me
>> of this.
>>
>> Analog SSB and CW modulation in a 3U to 6U cubesat may not be practical at
>> HEO apogee due to antenna size limits on a cubesat and power generation
>> capability of the cubesat limited number of solar cells. Digital techniques
>> were described as a way to make this work.
>>
>> FreeDV HF Digital Voice for Radio Amateurs was one of the types of
>> technologies mentioned just as an example. I found a demonstration at:
>> http://nicktoday.com/freedv-hf-digital-voice-radio-amateurs/
>>
>> Interesting, eh? A soundcard interface to your existing radio, sound card
>> in
>> the PC, we're teaching ourselves the first steps into digital radio ...
>> getting ready for the future.
>>
>> I've only had to interface my soundcard interface to my Yaesu 857D just
>> once. The interface remains stable from a hardware point of view. My PC
>> runs
>> the appropriate software for FUNcube telemetry, SSTV from ISS and prior
>> ARISSat-1, PSK31, JT65, RTTY ... and when I get some time in between
>> preparing the next issue of the Journal I'll add the software for the
>> FreeDV
>> codec.
>>
>> Perhaps we'll hear more interesting ideas or a fresh approach! At least we
>> could have a thread with some fun discussion ...
>>
>> --
>> 73 de JoAnne K9JKM
>> k9jkm@xxxxx.xxx
>> AMSAT VP User Services
>>
>>
>>
>> _______________________________________________
>> 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://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://amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 3
Date: Wed, 22 Oct 2014 07:49:49 -0500
From: "JoAnne K9JKM" <joanne.k9jkm@xxxxx.xxx>
To: <amsat-bb@xxxxx.xxx>
Subject: Re: [amsat-bb] Going Digital Someday
Message-ID: <5447a7ed.4510330a.3f59.290d@xx.xxxxxx.xxx>
Content-Type: text/plain; charset="us-ascii"
> If that were true then it follows that the modulation
> currently used with Codec2 Digital Voice is not practical
> for HEO either.
Quite true. The new HEO proposal warned that their scheme is not a
replacement for AO-13. When most of hear "HEO" we visualize each QSO with
its own discrete frequency on a VFO. The new satellite guys visualize many
error corrected digital signals up and down; perhaps a multiplexed method.
The satellite will need some processing power for error correction up there
as well.
Hams learning how to interface a codec with their rig is merely a stepping
off place.
Sooner or later they'll write up their proposal. I hope to run it in the
AMSAT Journal. Give them time to work on it.
--
73 de JoAnne K9JKM
k9jkm@xxxxx.xxx
------------------------------
Message: 4
Date: Wed, 22 Oct 2014 17:00:09 -0400
From: Rick Walter <wb3csy@xxxxx.xxx>
To: "amsat-bb@xxxxx.xxxx <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] AMSAT Journal Sep/OCT 2014
Message-ID:
<CAJckjgOCqn4yQL43jPFGByqBqD+sTts_6zwM-tHm1dgEXs=Ang@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
I just received the latest AMSAT Journal in the mail today (Lancaster, PA).
At first glance it looks great. I'm looking forward to reading all the
articles. Thanks to all involved for a job well done!
Rick - WB3CSY
--
Sent from Rick's gmail account
------------------------------
Message: 5
Date: Wed, 22 Oct 2014 18:25:51 -0300
From: Amsat Argentina <amsatlu@xxxxx.xxx>
To: amsat-bb <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] Saturday Oct-25 14hs GMT Betty V Balloon Launch
Message-ID:
<CAAVgVk_0h2950uwKpetYJBVa9OD2TFyTzTMkjFM4ZwjVov_HAA@xxxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
Amsat Argentina launch from Victorica, La Pampa Province, Argentina,
Balloon Betty V, carrying a Linear Transponder Up:435.850 KHz +/- 15 KHz
LSB, Down: 145.850 KHz -/+ 15 KHz USB 200mW.
Will include also FM Voice Repeater up:435.950 (123Hz CTCSS), down:145.950
2W, with CW ID & TLM, APRS Beacon on 144.930/145.950, SSTV R-36 pictures
live on 145.950. DMTF Commands for users & control.
On board video 2 GoPro-3 cameras. Vaisala sonde around 403 MHz. More info
on http://amsat.org.ar/globo25.htm Tracking http://aprs.fi?call=lu7aa-11
<http://aprs.fi/?call=lu7aa-11> & http://lu7aa.org.ar/vor.asp
Coordination previous & during flight 7095 KHz LSB.
Launch experiments toward CARPOSAT/LUSEX satellite platform validation
tests.
73, Amsat Argentina
info at amsat.org.ar
------------------------------
Message: 6
Date: Thu, 23 Oct 2014 10:35:08 +0000 (UTC)
From: M5AKA <m5aka@xxxxx.xx.xx>
To: AMSAT BB <amsat-bb@xxxxx.xxx>
Subject: [amsat-bb] LituanicSAT-2 + 4M lunar payload
Message-ID:
<293008537.88131.1414060508489.JavaMail.yahoo@xxxxxxxx.xxxx.xxx.xxxxx.xxx>
Content-Type: text/plain; charset=UTF-8
The LituanicaSAT team has announced on Facebook that the LituanicaSAT-2
CubeSat with propulsion will be coming soon
http://amsat-uk.org/2014/10/23/lituanicasat-2-announced/
The 4M Lunar amateur radio JT65B payload launches 1800 UT today - watch a
video of of Beijing's Chang Zheng CZ-3C/G2 launcher at
https://www.facebook.com/video.php?v=781398611903190
4M lunar payload - live TV coverage
http://amsat-uk.org/2014/10/15/4m-lunar-payload-integrated-keps-released/
----
Trevor M5AKA
AMSAT-UK
Website http://amsat-uk.org/
Facebook https://www.facebook.com/amsatuk
Twitter https://twitter.com/AMSAT_UK
----
------------------------------
_______________________________________________
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://amsat.org/mailman/listinfo/amsat-bb
End of AMSAT-BB Digest, Vol 9, Issue 363
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