434.100 MHz downlink received September 12, 2024 by PE0SAT
On April 21, the FCC announced that AST SpaceMobile (AST & Science, LLC) will be using the Amateur 430 MHz band for 248 satellites in its planned Low-Earth-Orbit constellation which aims to provide global cellular broadband communications.
Center frequencies are 430.5 MHz, 432.3 MHz, 434.1 MHz, 435.9 MHz, 439.5 MHz with 50 kHz bandwidth.
Read the FCC announcement at https://docs.fcc.gov/public/attachments/DA-26-391A1.pdf
434.100 MHz downlink received September 12, 2024 by PE0SAT
AST & Science LLC (AST SpaceMobile) currently have five Bluebird commercial satellites that use the amateur radio 430-440 MHz band. They were launched into Low Earth Orbit on September 12, 2024.
For an explanation of the problems these satellites cause see this post by AMSAT-DL President Peter Gülzow DB2OS https://community.libre.space/t/asts-bluebird-1-5/12255
Despite not being amateur satellites the first five commercial satellites use these amateur frequencies for telemetry links with a 50 kHz bandwidth: 430.5, 432.3, 434.1, 435.9 and 439.5 MHz.
AST SpaceMobile are planning to launch a further 243 satellites also using 430-440 MHz for TT&C. AST SpaceMobile say each UHF TT&C beam will support one command channel and one telemetry channel and the channel bandwidth will be between 64 kHz and 256 kHz.
In February they submitted a request to the FCC Space Bureau for use of the amateur band worldwide
https://apps.fcc.gov/els/GetAtt.html?id=371448&x=.
Also see their June 20 filing https://www.fcc.gov/ecfs/document/106201991509823/1
The 430-440 MHz band is used for a variety of Amateur Radio applications, examples include amateur space communications, weak-signal SSB, digital television, data communications, repeaters and other applications. The proposed 243 satellite constellation will cause interference to amateurs world-wide.
Read the detailed comment submitted to the FCC by the RSGB
https://fcc.gov/ecfs/document/10721151315294/1
The FCC wants to know what you think of this proposal, you can submit an Express Comment to the FCC by July 21 at
https://www.fcc.gov/ecfs/filings/express?proceeding[name]=25-201
If preferred you can submit a more detailed Standard Comment with .doc, .txt or .pdf attachments at https://www.fcc.gov/ecfs/filings/standard
Enter 25-201 into Proceeding(s) field and click on the pop-up which says ’25-201 SPACE BUREAU ACCEPTS FOR FILING AST & SCIENCE, LLC MODIFICATION APPLICATION’ fill in required fields and attach your comments file.
AST SpaceMobile say they have ground stations in Australia, Argentina, Bulgaria and Korea.
In April the FCC responded with these questions to AST
https://forum.amsat-dl.org/cms/index.php?file-download/7502/
AST replied in May to the FCC questions regarding their filing, see their answer regarding IARU
https://apps.fcc.gov/els/GetAtt.html?id=376295
Table 1 – Frequencies Reflecting the Global Capabilities of the SpaceMobile System
June 20 AST Filing
https://www.fcc.gov/ecfs/document/106201991509823/1
June 20 FCC issued this Public Notice SB 25-201 – comments on the proposed use of these frequencies should be submitted to FCC by July 21, see
https://www.fcc.gov/document/space-bureau-accepts-filing-ast-science-llc-application
A summary of ~80 of the Standard Filings on FCC Proceeding 25-201 AST & Science LLC (AST SpaceMobile) has been published by Docket Rocket
https://docketrocket.substack.com/p/comments-on-asts-tt-and-c-application
Including those that just missed the filing deadline a total of 2332 comments were submitted. You view them at
https://www.fcc.gov/ecfs/search/search-filings/results?q=(proceedings.name:(%2225-201%22))
For some background on FCC attitudes see the interview the Chief of the FCC’s Space Bureau, Jay Schwarz, gave to the American Enterprise Institute (AEI). It primarily concerns the ITU-R EPFD limits but it reflects the new thinking at the FCC about getting rid of “outdated assumptions about system design and spectrum use”
How the FCC Space Bureau is Rethinking the Rules of Space
https://www.aei.org/technology-and-innovation/how-the-fcc-space-bureau-is-rethinking-the-rules-of-space/
PCMag story July 18: Ham Radio Users Clash With Starlink Rival AST SpaceMobile Over Spectrum Use by Michael Kan KB6IRQ (@Michael_Kan on X)
https://www.pcmag.com/news/ham-radio-users-clash-with-starlink-rival-ast-spacemobile-over-spectrum
PCMag story August 6: No Interference? AST SpaceMobile Defends Use of Ham Radio Spectrum by Michael Kan KB6IRQ (@Michael_Kan on X)
https://www.pcmag.com/news/no-interference-ast-spacemobile-defends-use-of-ham-radio-spectrum
PCMag story August 8: Ham Radio Users Explain Why They’re Worried About AST SpaceMobile’s Satellite Plans by Michael Kan KB6IRQ (@Michael_Kan on X)
https://uk.pcmag.com/wireless-carriers/159498/ham-radio-users-explain-why-theyre-worried-about-ast-spacemobiles-satellite-plans
AMSAT-UK 
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