N1PEB
New Member
Posts: 38
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Post by N1PEB on Nov 1, 2017 14:42:43 GMT -8
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N1PEB
New Member
Posts: 38
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Post by N1PEB on Nov 2, 2017 0:57:48 GMT -8
Sorry I posted this in current discussion, can an admin move to general discussion please?
MODERATOR: This is fine in Current Discussions. Thanks for posting. We eventually move to General Discussions after they are no longer "current".
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N1PEB
New Member
Posts: 38
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Post by N1PEB on Nov 8, 2017 6:15:36 GMT -8
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Post by wd9ewk on Nov 17, 2017 17:32:35 GMT -8
Hi! This appears to be a parrot repeater, using separate uplink/transmit and downlink/receive frequencies. Hopefully the builders release more information as promised. This will make the satellite more compatible with ground stations using any number of 70cm D-Star radios, but users will have to adjust both the uplink and downlink frequencies to compensate for Doppler as the satellite passes overhead. For example, a group of 5 memory channels should cover most of the passes when the satellite is in view... - RX 435.535, TX 437.315 (or memory with 435.535 & +1.780 MHz offset)
- RX 435.530, TX 437.320 (or memory with 435.530 & +1.790 MHz offset)
- RX 435.525, TX 437.325 (or memory with 435.525 & +1.800 MHz offset)
- RX 435.520, TX 437.330 (or memory with 435.520 & +1.810 MHz offset)
- RX 435.515, TX 437.335 (or memory with 435.515 & +1.820 MHz offset)
Since most D-Star radios tune in steps no smaller than 5 kHz, there may be points during these passes where you are not able to transmit to the satellite or hear the downlink until the Doppler shift allows the uplink and/or downlink frequency used on the ground to line up with the satellite.
There have been one or two other D-Star satellites launched in recent years, but they never operated. Just over 10 years ago, there was a test using D-Star through the AO-27 satellite. From the Wayback Machine....
web.archive.org/web/20161002022044/http://ao27.org/
Unlike the D-Star One satellite, AO-27 was a satellite that operated as a cross-band repeater, normally for analog FM. AO-27 used an uplink frequency of 145.850 MHz and a downlink around 436.795 MHz (+/- 10 kHz for Doppler). The 2007 test listed on that web page (scroll down to the bottom of the page) had each station using two radios - one for the 2m uplink (both stations used an IC-2200 2m mobile radio), and the other for the 70cm downlink (one used an IC-2820H, the other an IC-91AD). The uplink radios were set up as if they were being used on a simplex frequency with CQCQCQ as the URCALL.
There are some good hints on that web page to keep in mind when using D-Star through this new satellite. It would have been nice if our radios could do D-Star with 2.5 kHz tuning steps instead of 5 kHz steps, but (other than maybe the IC-9100) we don't have that option. Not being able to operate full-duplex, where you can hear the satellite's downlink while transmitting, will make the new D-Star One satellite a little tougher than what those guys did on AO-27 in 2007.
73!
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N1PEB
New Member
Posts: 38
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Post by N1PEB on Nov 18, 2017 3:26:06 GMT -8
I’ll start programming my TH-D74 now Patrick, thanks for the information. Sounds like it will be a challenge to work, but it is always fun trying new things. Just checked the Orbital Systems web site and no further updates at this point.
Looking forward to hearing more discussions on the D-Star One SAT during the D-Star Roundtable Net.
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Post by wd9ewk on Nov 18, 2017 8:42:34 GMT -8
I’ll start programming my TH-D74 now Patrick, thanks for the information. Sounds like it will be a challenge to work, but it is always fun trying new things. Just checked the Orbital Systems web site and no further updates at this point. Looking forward to hearing more discussions on the D-Star One SAT during the D-Star Roundtable Net. Updates seem to be rare from that group. I would like to know more about how they implemented D-Star - i.e., did they cannibalize Icom radios (or the TH-D74), or are they using their own software with other radios? Some university CubeSat satellites have gone cheap with the comms, by taking a small HT out of its case and putting that in the satellite. I would like to see this be a success, but I won't hold my breath... More information on amateur satellites can be found at: amsat.orgamsat-uk.organd many other sites. BTW AMSAT's newest satellite, Fox-1B - also referred to as RadFxSat-1 and now called AO-91 after reaching orbit and transmitting telemetry - was launched early this morning from Vandenberg AFB in southern California. Not a D-Star satellite, but a small satellite with an analog FM repeater that also carries telemetry on the 145.960 MHz downlink frequency. Three more Fox-1 satellites are due to be launched over the next few months, and the first of these satellites - AO-85 - was launched in October 2015. AO-85 is working well, over two years since its launch. 73!
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N1PEB
New Member
Posts: 38
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Post by N1PEB on Nov 25, 2017 4:34:52 GMT -8
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Post by wd9ewk on Nov 28, 2017 7:37:28 GMT -8
Hi! The rocket carrying D-Star One and other satellites had a failure shortly after launch earlier today. Russian media reports, along with tweets from other sources, are saying that the rocket crashed into the Atlantic Ocean. None of the secondary payloads were deployed. From RussianSpaceWeb: www.russianspaceweb.com/meteor-m2-1.html#anomaly
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N1PEB
New Member
Posts: 38
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Post by N1PEB on Nov 30, 2017 4:39:14 GMT -8
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