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RadFxSat (Fox-1B) Launch Delayed; AMSAT Asks for Patience During Commissioning


The launch of the Delta II vehicle carrying RadFxSat (Fox-1B) and other payloads has been delayed, due to a faulty battery on the booster, United Launch Alliance (ULA) announced on November 6. The launch now is scheduled for no earlier than Tuesday, November 14. RadFxSat is one of four CubeSats making up the NASA ELaNa XIV mission, riding as secondary payloads aboard the Joint Polar Satellite System (JPSS)-1 mission, which will launch from Vandenberg Air Force Base, California.

RadFxSat is a partnership with Vanderbilt University’s Institute for Space and Defense Electronics (ISDE) and hosts four payloads for the study of radiation effects on commercial off-the-shelf components. It will carry a Fox-1 style FM U/V repeater with an uplink on 435.250 MHz (67.0 Hz CTCSS) and a downlink on 145.960 MHz. Satellite and experiment telemetry will be downlinked via the DUV subaudible telemetry stream, which can be decoded using FoxTelem software.

AMSAT Vice-President Engineering, Jerry Buxton, N0JY, said RadFxSat/Fox-1B will automatically come up in beacon mode, transmitting a beacon and voice ID (“RadFxSat Safe Mode”) every 2 minutes, starting about 50 minutes after deployment. He said AMSAT command stations will want to see voltage and current data to determine that the spacecraft is healthy and to conduct various tests before opening it up for general use.

Telemetry should begin about 55 minutes after deployment. “[F]or the next 72-96 hours at least, as we look for successful startup, watch the general health and function as the satellite begins to acclimate to space, and perform the on orbit checkout,” Buxton said. Ground stations are invited to continue uploading received telemetry for the life of the satellite.

Those using FoxTelem to capture telemetry are asked to check “Upload to Server” in the software’s settings and make sure that ground station parameters are provided. “You can help AMSAT and everyone waiting to get on the air with RadFxSat tremendously, by capturing RadFxSat telemetry,” Buxton said.

Patience and Good Manners Urged

In the initial beacon mode, the transmitter is limited to 10 seconds “on” time, followed by a 2-minute “off” cycle. “If we are seeing good data from user telemetry data, it is likely when it comes over the US for the first good pass, we will command it from beacon mode to normal safe mode, which then puts RadFxSat in full, but still safe mode, operation and transmits a full two frames of telemetry,” Buxton said.

Buxton called on the satellite community to be “polite and patient” as RadFxSat is commissioned.

“The on-orbit check-out procedure is similar to Fox-1A/AO-85 and could be completed in as little as a few days, if we have the cooperation of the users,” he said. “It is very important — not to mention just plain good amateur operating practice — to refrain from using the transponder uplink, so we can do the on-orbit tests, including when we turn on transponder mode for testing. I can’t stress enough, the importance of this cooperation, not just for us but for all users, simply having a little patience so we can conduct the tests as quickly and accurately as possible.” 

Buxton said AMSAT would “make it broadly known” when the transponder is available for general use. “If you hear someone on the transponder, please don’t assume that it is open for general use,” he said. “Check the AMSAT website, Facebook, Twitter, to be sure you’re not accidentally jumping in and unwittingly interfering with the commissioning process.” — Thanks to AMSAT News Service 



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