Slow-Scan TV (SSTV)

Slow-Scan Television (SSTV) has been around in ham radio for 50+ years. Initially, SSTV required expensive and complicated equipment, but thanks to computers and today’s digital modes, it’s easier than ever to start experimenting with one of ham radio’s oldest specialty modes!

How do you get started with SSTV? Read on!

What Is SSTV?

SSTV takes a static (non-moving) image and “scans” it from right to left and top to bottom, and transmits the image in three primary colors using audio frequencies (in the same bandwidth as a voice transmission). Because it uses just audio frequencies, any radio that can transmit and receive voice can also transmit and receive SSTV. That means you can use your HF radio, or your VHF mobile, or your VHF HT to send and receive SSTV! There are several popular “modes”, which vary in scan time and image resolution. Needless to say, there is a tradeoff between image speed and resolution – one of the popular modes is “Robot36” which transmits a single image in 36 seconds.

How Do I Get Started?

If you have an interface between your computer and radio for digital modes (FT-8, BPSK, etc.), that interface should work for SSTV. Download and install SSTV software (see right) and configure to see the audio source for your interface. Most software supports “templates” where you can add overlays to images for CQ and your callsign or freeform text. There’s usually plenty of SSTV activity to receive on 14.230 MHz on evenings and weekends.

For VHF/UHF radios (for ISS SSTV), most mobile radios have a “data” port on the back of the radio that you can interface with. If you just want to receive, you can use the Ext. Speaker jack with a sound card audio interface (verify levels first). You will also need to track the ISS orbits to know when the ISS will be overhead (highest apogee passes are best).

Even if you don’t have a wired interface, you can still have fun with SSTV. You can use smartphone apps to send and receive SSTV images, just by holding the phone up to your radio microphone or speakers (audio coupling) – it works best in a quiet room.

RWK SSTV Events

  • ARISS SSTV Is (Hopefully) Back In Operation
    By Chip Coker KD4C After an extended outage due to equipment failure, the ability of the ARISS (Amateur Radio on the International Space Station) to send SSTV is back! At long last, the ARISS Team is conducting tests of the SSTV system for the next few days. Welcome Back SSTV! The test is scheduled from…
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  • ARISS SSTV Year-End 2021 Event
    By Chip Coker KD4C It was great to see all the interest and activity around the Year-End ARISS SSTV event from Dec 26-31. These events are typically done 2-3 times a year and are fairly well advertised in advance. In the November Chawed Rag, I showed how easy it is to receive SSTV from the…
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  • ARISS Operating SSTV In Early December
    By Chip Coker KD4C (source AMSAT) One of the easiest ways to get started with amateur satellites is to start with maybe the most known and prominent one – the International Space Station (ISS). It orbits around 250 miles overhead and the orbit period is around 90 minutes, which means that you can hear more…
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SSTV on HF

SSTV is used on all HF bands, but use is concentrated primarily on 20M (14.230MHz), where you can hear activity at all times of the day or night.

SSTV on VHF

SSTV is also possible on VHF/UHF FM (either through a repeater or simplex). You must be aware of the transmit time for images so that you don’t stress or time out your radio (or a repeater). Because it’s FM, SSTV images are fairly clear.

SSTV on the ISS

The International Space Station has SSTV generation capability and periodically will conduct SSTV events for up to a week at a time. You can obtain a nice certificate from the ARISS project for uploading a received image from the ISS. Check the ARISS page for the latest news and what’s currently operational:  https://www.ariss.org/current-status-of-iss-stations.html

Popular SSTV Software

MMSSTV (Windows)

QSSTV (Linux)

CQ SSTV (iPhone)

Robot36 (Android)