ISS HAMTV

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  • Modulation: DVB-S
  • Freq: 2395MHz
  • Symbol Rate: 2MS/s
  • FEC: 1/2

Example Receiver Setup by Dave G8GKQ

Transport Stream

Video: MPEG2 yuv420p 903kb/s 29.97fps

Audio: MP2 44.1KHz Stereo s16p 256kb/s

Samples

  • Early Recording by Colin G4KLB of Camera Commissioning Transmission (April 2014): HAMTV_G4KLB_13_04_2014_19h18_40.TS (63MB)
    • TS is corrupted and may not play in all players. mplayer appears to be the most reliable.

Video Resolution

At the Transmitter:

The 16:9 signal from the ISS Camera is squashed into NTSC_DV format, at 720x480. This is subtly resized from NTSC_D1, which is 720x486, for Digital capture (so that the pixel dimensions are divisible by 16).

At the Receiver:

NTSC_DV & NTSC_D1 pixels have an aspect ratio (PAR) of ~0.89 (width/height, making the pixel tall and thin). So for accurate display on a square pixel monitor we can upsample the height (or downsample the width), for a resolution of 720x540 for 4:3. (or 640x480 for downsampling)

Which would be stretched back to 940x540 to restore the 16:9 of the camera! Or of course, stretch first, then downsample to 854x480 as displayed by Tutioune, to keep the picture information without redundant extra pixels.

PIDs

Video PID: 256 Audio PID: 257

Tutioune Setup

Tutiuone receiving HAMTV, using S-band Downconverter (Credit: G8GKQ)

SR (kS): 2000

Freq: 2395MHz

FEC: 1/2 - Checked.

Low SR - Checked.

ISS - Checked.

AutoPID: OFF

Video PID: 256

Audio PID: 257