STRaND-1 – I think I have a faulty antenna!

Over the weekend I have made a couple of attempts at receiving the STRaND-1 satellite telemetry and indeed have a few IQ wave files that require processing but I don’t expect to get any successful decodes out of them as they have been rather patchy and variable.

During the pass on Sunday evening I wasn’t getting anything and as it neared the end of the predicted pass I gave up and picked up the antenna tripod to put it away and suddenly a strong signal appeared on the SDR waterfall! I suspect I have a problem with the antenna, either a faulty connection in the coax or connectors that was briefly corrected by the act of moving the tripod. It isn’t the first time I have had issues and will have to investigate further.

The weekend wasn’t a total loss, I did manage to capture a reasonable NOAA-18 pass on Sunday afternoon! Between washing the cars and doing some gardening!

A Frustrating Afternoon

I have recently took possession a ‘new’ laptop, a nice Lenovo Thinkpad. with a Core i3 and Windows 7 Professional.

I was trying to use it this afternoon with the FUNCube Dongle and having no luck at all getting it to work! I had planned to decode some NOAA-APT transmissions and hastily reverted to my older laptop only to discover that it wasn’t receiving anything either.

In the end I traced it down to a faulty BNC coupler! I remember it was raining last time I used it and it did get slightly damp, so suspect there is some corrosion. Unfortunately by the time I had sorted it out I missed most of the overhead pass of NOAA-19.

I did manage to get two poor decodes of NOAA-18 and NOAA-15 but as you can see I was struggling with fading signals and interference.

NOAA-15 11-Nov-2012

NOAA-18 11-Nov-2012

What was interesting, and not seen before was the visible image (on the right) seems to change when it goes into darkness.

Damn you!

Some NOAA APT Decodes

Listening to the scanner this morning I heard the distinctive APT ‘chiming’ sound as one of the NOAA polar orbiting weather satellites was making a pass. It has been a while since I have done any APT decoding, so decided to capture some of the passes of NOAA-18 and NOAA-19 this afternoon.

The first two passes of both satellites were North to South around 20-30 degrees elevation, this image was the best of the them, the UK is in the upper left. 

NOAA-19 11:32 UTC 21-OCT-2012

The following passes were much higher, almost overhead, there was some interference on this NOAA-18 pass due to pagers and I got disorientated whilst hand holding 2-meter YAGI, hence the lost of signal near the top of the image.

NOAA-18 14:02 UTC 21-OCT-2012

However the NOAA-19 pass before it was much better. What is noticable is the bands of darkening, caused by nearby buildings and some large trees shielding the satellite from my the line of sight position.

NOAA-19 11:12 UTC 21-OCT-2012

All images were decoded realtime using the SDR-Radio program, received by the FUNCube Dongle connected to the InnovAntennas Yagi.

First FCD experiments

I was feeling shattered after a hectic Christmas and being back at work, so it was nice with the New Year break to have a chance to recover. I have spent the weekend around the house and so had a good chance to try out my FUNCube Dongle (FCD) to do some proper satellite reception!

First off I spent a while calibrated my dongle using the excellent user guides available on the yahoo group, and getting to grips with the excellent but somewhat daunting SDR-Radio application. 

I fired up another of my ancient laptops a Sony Vaio, with XP and a pitiful 512MB of RAM. It is a nice machine, with an excellent large display but is a little underpowered. However undeterred with the prospect of some timely satellite passes I installed the necessary software and set off to the summerhouse at the top of the garden with my YAGI and a warm coat.

NOAA Weather Satellites

As I posted about back in October I was hoping if I did get an SDR radio to capture some of the APT images broadcast by the NOAA polar orbiting weather satellites. (Noaa 15, 18 and 19 are currently active)

The SDR-Radio application has the facility to decode the noaa images directly and along with it’s built in satellite prediction and doppler correction features it was fairly easy to get some decent images. The huge advantage of the SDR system is being able to alter the bandwidth to accommodate the 34KHz deviation required (as you can see in the image above)

The image above was captured on 31st December at 13:26 GMT from NOAA-19 on 137.100MHz, the left image is the IR, the right being the visible image. If you click to enlarge you can clearly see Spain and the Balearic Islands at the bottom, the UK and most of Northern Europe is covered in dense cloud and is rapidly going into shadow. There is some noise, caused in part by pager transmissions and some course manual doppler correction.


As I posted before Christmas this little satellite is still going strong but it’s time is very short as reaches the atmosphere. I have been able to receive four afternoon passes in the last two days

As you can see from the image shows, the FCD makes the entire ARISSat-1 2 meter downlink band plan available. The slight slope shows the doppler effect.

On the left you can clearly see the Morse code beacon and the BPSK telemetry segment and the right the FM voice and SSTV transmission. I am really really pleased to have successfully managed to decode some telemetry frames before she meets her fiery death. The decode was done after the passes by processing the recorded IQ wav file. I probably have just one more day to have a chance to try to decode some live telemetry and hopefully forward it via the internet to ARISS.
It goes without saying I have some excellent audio and decoded a couple of SSTV images too.

I love my new toy!

NOAA Weather Satellites and SDR

One site I have in my Google Reader list and check regularly is the Hackaday blog

One project they recently featured was Grab your own images from NOAA weather satellites

The main project website describes using a Softrock homebrew SDR(software defined radio) to get the necessary audio file to import into WxImg decoder.

I have been toying with getting hold of the AmSat-UK FunCube SDR dongle, which is now available from Martin Lynch and Sons and using it in a similar way after seeing this article a while back.