Navigation

     Contact Details

     Peter Miles
     Northam, Western Australia

     

 

     Email

     

 

       Social Media

             

 

    Buy me a coffee

If you found information on this site interesting, beneficial, or learned something new, please consider buying me a cup of coffee by clicking the coffee cup below. It helps keep the website going and is greatly appreciated.

 

 

 

FLTSATCOM-7 (USA-20)

FLTSATCOM-7 (USA-20) Background and technical overview.


HOME  > OPERATIONAL > MODES & FREQUENCIES > SATELLITES - RADIO TARGETS >

 

The old FLTSATCOM spacecraft had relatively simple repeater architecture. Some of its UHF transponders did not provide the sort of modern authentication and access control we associate with contemporary military satellite systems.

Consequently, unauthorized users discovered that they could transmit on the satellite uplink and hear their signals come back down over a huge area.

Details

Satellite: FLTSATCOM-7 (USA-20)
Norad ID: 17181
Operator: US Navy
Status: Operational, however superseded by MUOS.
Frequency Range: 240.0 - 270.0 MHz VHF Down Link

 

Mode: FM
Altitude [km]: 36000 +/-  Near-geosynchronous, near-equatorial (Junkyard orbit) drifting eastward.
Tracking:  https://www.n2yo.com/?s=17181&live=1 

 

FLTSATCOM 7 (F7 / USA-20), the applicable historical frequency plan is Bravo. The FLTSATCOM architecture had 23 RF channels: ten 25-kHz channels, twelve 5-kHz narrowband channels, and one 500-kHz wideband channel.

Channel confirmation was achieved by monitoring the channel frequency for consistency with the band plan, verifying the bandwidth and antenna targeting to assess the SNR (signal-to-noise ratio).

Frequency
Bandwidth Status
250.55 25 kHz Fleet Broadcast
252.05 25 kHz Navy relay - Confirmed 2026
253.75 25 kHz Navy relay
255.45 25 kHz Navy relay
257.05 25 kHz Navy relay
258.55 25 kHz Navy relay
265.45 25 kHz Navy relay
266.95 25 kHz Navy relay
268.35 25 kHz Navy relay
269.85 25 kHz Navy relay
244.045 5 kHz AFSATCOM narrowband
244.055 5 kHz AFSATCOM narrowband
244.06 5 kHz AFSATCOM narrowband
244.065 5 kHz AFSATCOM narrowband
244.07 5 kHz AFSATCOM narrowband
244.075 5 kHz AFSATCOM narrowband
244.08 5 kHz AFSATCOM narrowband
244.085 5 kHz AFSATCOM narrowband
244.09 5 kHz AFSATCOM narrowband
244.095 5 kHz AFSATCOM narrowband
244.1 5 kHz AFSATCOM narrowband
244.11 5 kHz AFSATCOM narrowband
261.950–262.450 500 kHz Wideband

 

 
Reception
Reports

Date Time Frequency Details
       
Antenna: 5 Element Yagi for 250MHz. https://vk6ysf.com/yagi_250mhz_5el_20220925.html  
Software: SDR Software: SDR++Brown
Speech Note (Linux) speech-to-text tool that transcribe audio and translate between languages. https://flathub.org/en/apps/net.mkiol.SpeechNote

 

Screenshot 1  

 

 

References

Gunter's Space Page
SatelliteTracking

https://www.n2yo.com/?s=17181&live=1 

Wikipedia  

 

TOP OF PAGE

Page initiated 19 September, 2026 

Page last revised 19 September, 2026   

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

   Space Weather

   https://www.swpc.noaa.gov/

    

Michael Faraday born 22 Sep 1791

Shaping the modern electrical age, Michael Faraday (1791–1867) was a pioneering British scientist who transformed our understanding of electricity and magnetism. His discoveries included electromagnetic induction, which laid the foundation for electric generators and transformers, as well as the principles behind the electric motor.

   Notice Board

VK6YSF JS8Call and Olivia 8/250 operations.

Current activity is generally focused - though not restricted to - JS8Call operations on the 20, 30m, and 40m bands.

Olivia 8/250 is used occasionally on the 20m band.

Proposed band and mode activity is often communicated on HamSpots: https://hamspots.net/js8/ or my profile on 

X: https://x.com/vk6ysf97230 .  

Post date: 27 August 2026

 

Local Repeaters

Repeaters Page Updated - Expanded and refreshed information on VHF and UHF repeaters across Western Australia's Central Coast, Perth, the Avon Valley, and the Peel region. New AllStar Link information has also been added, including linked repeater details and gateway information across the State.

Repeaters details:

https://vk6ysf.com/local_repeaters.htm

 

AllStar Link notes:

https://vk6ysf.com/allstar_notes-20260703.htm

 

Post date: 27 August 2026

 

Western Australian SSTV net 

Popular Western Australian SSTV net for both digital and anolog SSTV.

Generally found at 7214.0kHz LSB every afternoon from 08:00 UTC (4:00pm WST)

For more details: https://www.wasstv.net/wasstv.net/index.html

Post date: 8 December 2025

 

VK6MJM LF (136kHz) and MF (474kHz) Beacon

VK6MJM is a  LF/MF station located in Manjimup, Western Australia.

Common Mode: FST4W 300 (Similar to WSPR)  

Note: other modes and sub-modes may be used.

Station details were presented by Peter Hall (VK6HP) at PerthTech 2024.Presentation PDF: Peter Hall VK6HP at PerthTech

QRZ Page: VK6MJM on QRZ.com

Post date: 10 March 2025

 

 

 

 

 

 

 

 

All content may be used for unlimited distribution with full credits.

Amateur Radio Station VK6YSF - Promoting amateur radio communication and experimentation.