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<p>Sorry, should be 400 Euros.</p>
<p>Ron<br>
</p>
<div class="moz-cite-prefix">On 12/9/19 07:07, Ron Economos via
Ground-Station wrote:<br>
</div>
<blockquote type="cite"
cite="mid:75a37ea1-f8ce-4d8a-096e-c647befc247a@comcast.net">
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<p>I've been using the Digital Devices Max SX8.</p>
<p><a class="moz-txt-link-freetext"
href="https://www.digital-devices.eu/shop/en/tv-cards/tv-cards-for-pcie/340/8-tuner-tv-card-dd-max-sx8-4/8-dvb-s2/dvb-s2x-full-spectrum?c=156"
moz-do-not-send="true">https://www.digital-devices.eu/shop/en/tv-cards/tv-cards-for-pcie/340/8-tuner-tv-card-dd-max-sx8-4/8-dvb-s2/dvb-s2x-full-spectrum?c=156</a></p>
<p>It can go down to 100 kSyms/s and can output raw bbframes. It's
also very tolerant to Doppler shift (capable of 30 kHz/s at 10
Msyms/s) . At high bandwidths, you probably won't need LO
sweeping.</p>
<p>It's supported in the Linux kernel starting at release 4.20.
Plug and play on Ubuntu.<br>
</p>
<p>It can also output raw IQ and demodulator IQ. Here's a video
showing demodulator IQ.</p>
<p><a class="moz-txt-link-freetext"
href="http://www.w6rz.net/sx8.mp4" moz-do-not-send="true">http://www.w6rz.net/sx8.mp4</a><br>
</p>
<p>It's a little pricey at 500 Euros.<br>
</p>
<p>Ron W6RZ<br>
</p>
<div class="moz-cite-prefix">On 12/8/19 17:05, Mike Parker via
Ground-Station wrote:<br>
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cite="mid:874209EC-00DA-44DF-8CF7-B5D3B6E42D60@gmail.com">
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A team headed by the University of Arizona is working on a 6-U
satellite that will fly at 500 km altitude. The satellite,
named CatSat after the UofA wildcat mascot, was described in a
paper presented at the Amsat Annual Meeting. We are shooting
for a launch that could be as early as one year from now. The
plan is to have a downlink using DVB-S2 modulation generated by
an FPGA on the AstroSDR card provided by Rincon Research. This
modulation was chosen so that hams that have been working phase4
ground DVB-S2X might receive and demodulate the link. We are
planning to transmit a limited number of ModCod’s. Modcod 7,
QPSK 3/4, and modcod 17, 8-PSK 9/10 are likely choices.
<div class=""><br class="">
<div class="">Two experiments plan to use DVB-S2 modulation on
the downlink. One involves transmitting high quality video,
and the other will capture and retransmit narrowband pieces
of the HF ham bands containing WSPR and FT8 signals.
Closing the link to our 6.1 meter diameter ground station
is no problem, and we are planning on a modulation bandwidth
up to 20 MHz and bit rates over 50 Mbps when using the
satellite’s inflatable directive antenna provided by
FreeFall. But closing the link to a ham 0.6 meter dish when
operating with an onmi-directional transmit antenna poses a
very different problem. We will likely require small
downlink bandwidths on the order of 200 kHz.</div>
<div class=""><br class="">
</div>
<div class="">We are looking for a demodulator to assist in
testing the satellite, and also a demodulator for use in the
ground station. So we are reaching out to you for
suggestions. We hope that an available commercially for an
affordable price, or perhaps something designed by a member
of this group. We have neither the desire or time to
reinvent the wheel.</div>
<div class="">Several things concern us we would appreciate
advice on.</div>
<div class="">1) We read with interest a paper by Downey,
Evans, and Tollis, “DVB-S2 Experiment over NASA’s Space
Network”. It said “ typical commercial DVB-S2 receivers are
not designed for symbol rates below 300 kbaud”. That is
consistent with our observation that many commercial
demodulators do not seem to have a lowest bandwidth
specification. Anyone know of one that goes lower in
bandwidth while having a high bandwidth capability?</div>
<div class="">2) We need to have a demodulator that will
output raw DVB-S2 frames, bypassing any transport layer
protocols which are normally used with DVB-s2 such as
Multi-protocol Encapsulation(MPE) or Geeric Stream
Encapsulation (GSE). Downey, Evans, and Tollis used a
Newtec MDM6000 modem. Is there a better or cheaper
solution? (I haven’t priced one yet).</div>
</div>
<div class="">3) Doppler shifts are also a concern, especially
at a low data rate, but we have a plan to solve that if
necessary using a local oscillator in the ground station that
is swept according to ephemeris predictions to de-Doppler the
signal before demodulation.</div>
<div class=""><br class="">
</div>
<div class="">Oh yes, some good news. The first of our 6.1
meter dishes has been reassembled in Rincon’s parking lot in
Centennial, CO. A picture with assembly in progress is
attached. I’m flying up tomorrow with a 10 GHz feed horn and
LNA to see if we can hear signals!</div>
<div class="">Mike Parker, KT7D</div>
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src="cid:part3.26AB5002.1634DEB9@comcast.net" border="0"></div>
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