AO-85 Slow Scan TV

Fox-1A / AO-85 SSTV image received by Roland PY4ZBZ

Fox-1A / AO-85 SSTV image received by Roland PY4ZBZ

On Sunday, December 13, Roland Zurmely PY4ZBZ received a Slow Scan TV (SSTV) image which had been uplinked to the amateur radio CubeSat Fox-1A / AO-85.

Roland says he was not prepared and the antenna was misguided but even so he managed to receive a recognizable image.

AO-85 was launched October 8, 2015 and transmits 5 kHz deviation FM on around 145.980/.975 MHz.

In the UK amateur radio transceivers are set to default to narrow FM filters (2.5 kHz deviation). If possible you should select your radio’s wider FM filter designed for 25 kHz channel spacing.

AO-85 information

Hints on how to receive Slow Scan TV from space are at

Roland PZ4ZBZ

AO-85 Commissioned


AO-85 (Fox-1A) Flight Unit

AO-85 has been formally commissioned and turned over to AMSAT-NA Operations, who are now responsible for the scheduling and modes.

The following guidelines are provided for users:

Uplink power should be on the order of minimum 200 W EIRP for full quieting at lower antenna elevation angles. Your mileage may vary. With an Arrow, 5 W has been used successfully to make contacts.

Polarity is important. The satellite antennas are linear. So, if you are using linearly polarized antennas, you will need to adjust throughout the pass. Full duplex operation facilitates these adjustments while transmitting and is highly recommended.

The downlink [145.980 MHz nominal] is very strong and should be heard well with almost any antenna.

Downlink audio is 5 kHz deviation, as expected. Many will perceive that the audio is “low.” This is an effect of the filtering below 300 Hz, which provides for the DUV telemetry, coupled with any noise on the uplink signal resulting from lack of full quieting or being off frequency. That makes for less fidelity than a typical receiver in terms of audio frequencies passed.

Transmit (downlink) frequency varies with temperature.  Due to the wide range of temperatures we are seeing in the eclipse cycle, the transmitter can be anywhere from around 500 Hz low at 10°C to near 2 kHz low at 40°C.

Receive frequency has been generally agreed to be about 435.170 MHz, although the AFC makes that hard to pin down and also helps with the uplinks that are off frequency.

Probably the most notable observations about AO-85 are an apparent lack of sensitivity and difficulty in turning on the repeater with the 67 Hz CTCSS when it is not yet activated, or holding it on by the presence of the CTCSS.  We have determined a probable cause for the sensitivity issue and while that can’t be fixed on AO-85 we are taking steps to prevent similar issues on the rest of the Fox-1 CubeSats.  The tone detection threshold along with the receive sensitivity issue makes it hard to bring up the repeater.  This is being addressed by adjusting the values for a valid tone detection in the other Fox-1 CubeSats now that we have on orbit information about temperatures and power budget. Full details will be in the Nov/Dec AMSAT Journal.

It is important to remember that science is the reason behind the Fox-1 satellites. Not only does science help with the launch cost, it provides a great amount of educational value both from the science payload and in amateur radio itself. The data-under-voice (DUV) telemetry is an excellent way to provide the science without sacrificing the use of the satellite for communications, which would be the case if higher speed downlinks were needed. DUV provides constant science as long as the repeater is in use, which in turn provides more downlink data for the science – a mutually beneficial combination.

Fox-1A is AMSAT-NA’s first CubeSat. Many new techniques are incorporated and lessons will be learned, as with any new “product.” The Fox-1 Project is a series of CubeSats. A total of five will be built and flown. Launches are scheduled for three more, and a new NASA CubeSat Launch Initiative proposal will be submitted for the fifth. We will incorporate changes from what we learn in each launch, to the extent possible, in subsequent Fox-1 CubeSats.

Of the four NASA sponsored CubeSats on the ELaNa XII launch October 8, we are sad to report that ARC1 was never heard from and BisonSat was lost after a few weeks of operation. AMSAT extends our deepest sympathy to the people who worked so hard on these projects. To our members, we want to say that the Fox Team is very proud and pleased that our first CubeSat is very successful and hopefully will be for some time.

AO-85 information

New version of Fox-1A Telemetry Decoder

Fox-1 CubeSat at the Dayton Hamvention - Image Credit ARRL

Fox-1 CubeSat at the Dayton Hamvention – Image Credit ARRL

Chris Thompson G0KLA has released a new version of the AO-85 (Fox-1A) telemetry decoder software FoxTelem 

I want to announce the release of FoxTelem Version 1.01. If possible, everyone should upgrade to this new version. In addition to some new functionality it fixes some bugs and issue that mean more data will be uploaded to the server.

This is a patch release. If you already have 1.00 installed then download the file

You can download it from:

Only two files have changed (plus the manual). Copy these files into your install directory
– FoxTelem.jar
– spacecraft/FOX1A_radtelemetry2.csv

You can also download the whole install file and install it in a new directory. You can use the settings menu to continue using your existing log files. Ask if you need assistance.

Lots has changed in this release and many bugs have been fixed. Please report any issues that you see.

Release notes:
* Allow the user to view and set the “track” attribute for each spacecraft (and other parameters)
* Better doppler tracking in IQ mode and more stable estimate of the received frequency
* Better Find Signal algorithm with tuning parameters for experts
* Read Time Zero from the server for each reset and use to plot graphs in UTC
* Set the default fcd frequency to 145930 so that Fox-1A, Fox-1Cliff and Fox-1D will be in the passband
* Allow the gain to be set on the FCD (rather than hard coded)
* Do not change the FCD LNA or Mixer Gain. Leave unchanged.
* Do not open the FCD unless the start button is pressed
* Fixed a bug where the last 2 bytes of the radiation telemetry were not decoded correctly
* Allow Vanderbilt radiation experiment to be graphed
* Allow user to select UDP or TCP for upload to the server (but use UDP for now please)
* Shorten the period between passes so that graphs look continuous
* Ignore duplicate high speed radiation frames – needed for processing data from the server
* Allow graphs to be hidden so that average or derivative is easier to see
* Notify the user when a new release is available
* Cleaned up the FFT trace with some averaging
* If showRawValues is checked then save CSV files as raw values
* Several updates to the manual

FoxTelem Software for Windows, Mac, & Linux

AO-85 (Fox-1A)

AMSAT-UK congratulates the Fox team

AMSAT-UK LogoOn behalf of all members of AMSAT-UK I send our congratulations the AMSAT team in the USA for all their hard work in recent years on FOX-1A which having been successfully launched, and from which telemetry signals have been successfully received and decoded on earth, is now known as AO-85.

This is a great achievement. I wish the team well during the forthcoming commissioning, and we all hope that the new satellite will have a long and useful life operating in the Amateur Satellite Service.


Martin Sweeting, G3YJO

Chairman AMSAT-UK

AO-85 (Fox-1A) FM Voice Transponder Activated

Keen amateur satellite operator Hope KM4IPF

Keen amateur satellite operator Hope KM4IPF

The 435 to 145 MHz FM voice transponder on AO-85 was activated during Friday, October 9 allowing many contacts to be made. Among those active on the satellite was 9-year-old Hope KM4IPF.

Hope is the daughter of Michelle N8ZQZ and James WX4TV, other radio amateurs in the family are Hope’s elder sister Faith WA4BBC and brother Zechariah WX4TVJ, her younger sister is studying for her licence.

In this video Hope KM4IPF describes her first AO-85 (Fox-1A) contact

Fox-1A Real-time track and Orbital Predictions (click on Draw Footprint to show coverage area)

Read the Fox Operating Guide to find out how to set up your handheld radio to work the satellite
Note: If your rig has selectable FM filters use the wider filter for 5 kHz deviation 25 kHz channel spacing.

Download your free copy of the AMSAT Journal Fox-1A Launch special issue

Fox-1A Launched

Jerry Buxton, N0JY talking about Fox-1A on NASA TV

AO-85 OSCAR Number Assigned for Fox-1A

Tony Monteiro AA2TX and Fox-1 model

Tony Monteiro AA2TX and Fox-1 model

Willian (Bill) Tynan, W3XO, AMSAT-NA OSCAR Number Administrator has issued the following release:

I have been informed of the successful launch today, October 8, 2015 of the AMSAT-NA-built Fox-1A CubeSat. I am also informed that the satellite has been heard by several amateurs in various countries.

This successful launch comes after years of diligent and dedicated work on the part of AMSAT-NA volunteers including Tony Monteiro, AA2TX, who became a silent key in March, 2014.  It was Tony who spearheaded and guided the work on all AMSAT-NA CubeSats until his untimely passing. Thus, it is only fitting that this spacecraft be dedicated to his memory.

Following Tony’s death, the work of completing and preparing for launch fell to Jerry Buxton, W0JY, who took over Tony’s post of AMSAT-NA’s Vice President for Engineering and saw to Fox-1A’s successful completion and its preparation for launch.

All of those who had a part in designing, constructing and testing Fox-1A and its various subsystems are to be congratulated for jobs well done.

Fox-1A Flight Unit

Fox-1A Flight Unit

Since Fox-1A was properly coordinated through IARU as an Amateur Radio satellite, has been successfully launched and its signals have been received; I, under the authority vested in me by the AMSAT-NA President, do hereby issue to Fox-1A the designation AMSAT-OSCAR-85, or AO-85.

May AO-85 serve the radio amateurs of world for many years to come.

[Thanks Bill, W3XO, and AMSAT-NA for the above information]

Fox-1A Launched

Jerry Buxton, N0JY talking about Fox-1A on NASA TV