TRUDO RADIO CLUB

Slow Scan Television (SSTV) is a technique that allows radio amateurs to transmit still images over a regular voice channel. It’s somewhat similar to television, but greatly slowed down and optimized for narrow bandwidths. Despite its long history, SSTV remains popular on HF, VHF and even via satellites.

An example of an SSTV image

Instead of transmitting video in real time, an SSTV image is converted line by line into audio tones. These tones fit within the 3 kHz audio bandwidth of a standard SSB channel. On the receiving side, software converts these tones back into a picture. This allows amateurs worldwide to exchange images, even with limited signal strength.

Low entry barrier SSTV requires no special hardware. A transceiver, a computer or smartphone, and suitable software (such as MMSSTV or Yoniq) are all you need.

SSTV is used for: • exchanging photos during QSOs • demonstrations and training • emergency communication where visual information is important

Because SSTV fits within a narrow bandwidth, it can be used on both HF and VHF/UHF. This makes it usable worldwide.

There are several transmission modes, each with its own speed and resolution. Some commonly used examples: • maritime and aviation communication • emergency communication and emergency networks • contest traffic • weak‑signal communication on VHF/UHF