SSTV etiquette — sharing a frequency for minutes at a time
Voice operating conventions assume you can hear whether someone is talking and that transmissions last seconds. Neither holds for pictures. A five-minute transmission with no callsign audible in the middle of it changes what ‘is this frequency in use?’ means, and most SSTV rudeness is an honest mistake by someone applying voice habits to a mode that does not fit them.
Listening properly
The standard courtesy — ask whether the frequency is in use, wait, ask again — was designed for a mode where an occupied frequency sounds like a voice. SSTV breaks that assumption in two ways.
First, a transmission in progress carries no callsign you can hear. Second, it may have another four minutes to run. Tune in halfway through a Scottie DX and you will hear warbling tones from someone who cannot answer you and will not know you asked.
- Listen for a full cycle. Three minutes minimum; five if you want to be sure. Long enough for a picture to end and a callsign to appear.
- Watch the waterfall, not just the speaker. A picture in progress is obvious on a waterfall long before you can identify it by ear.
- Never transmit over a picture. You do not merely interrupt — you destroy several minutes of someone’s transmission and everyone else’s copy of it.
Leaving room
The most common complaint about SSTV operators is not interference. It is monopolisation: a station transmitting picture after picture with no meaningful gap, on a shared frequency, for an hour.
- Pause after every transmission — long enough for someone to call you or to break in. Thirty seconds is not excessive.
- Do not resend the same picture repeatedly. If nobody answered, the picture is not the problem.
- Choose shorter modes when the band is busy. Robot 36 asks 36 seconds of a shared frequency; PD290 asks 289. Both are legitimate; only one is considerate at peak time.
- Move off the calling frequency once you have made contact — the same convention as voice, and more important here because you occupy it for longer.
Who is actually watching
This is worth stating plainly, because it is easy to forget while sitting alone in a shack. Anything you transmit as a picture can be decoded by anyone with a receiver.
That includes people with no licence and no connection to the hobby — a twenty-pound SDR dongle and free software is the entire barrier to entry. It includes automated receivers that archive what they copy, publish it, and index it. Pictures put on the air are public and, for practical purposes, permanent.
- Nothing private. Not addresses, not personal information, not anything about someone who did not consent to it.
- Nothing you would not put on a postcard. Amateur radio is not a private channel, and UK licence conditions include requirements about content — see the UK licence and images.
- Nothing commercial. Broadcasting and advertising are outside what the amateur service is for.
Identify properly
The callsign banner is not just courtesy. UK licence condition 6(21) requires the callsign to be given “in voice or other appropriate format consistent with the mode of operation” — and for an image mode, a legible callsign in the picture is exactly that.
Which puts the emphasis on legible. A callsign that arrives as a smear of noise has identified nobody. Size it like a road sign, on a solid contrasting band — see preparing pictures and the licence page.
Send reports back
SSTV runs on reciprocity. Somebody spent two minutes of transmitter time and a slice of a shared frequency sending you a picture; telling them how it arrived costs you nothing and is the entire feedback loop by which people improve their signals.
An RSV report and a sentence is plenty. On the Open Signal network this happens automatically — every copied picture files a report with callsign, grid, SNR and distance — which is why reception reports accumulate for marginal contacts that would never have generated one by hand.
Beacons and unattended operation
An automatic beacon is a genuinely useful thing — it lets other stations find you and builds propagation data. It is also the fastest way to irritate a band.
- Not on a busy calling frequency.
- Generous intervals — minutes between transmissions, not seconds.
- 5 W ERP is the licence limit for a Radio Beacon under any class — 25 W ERP for Intermediate and Full holders, but only with an RSGB-allocated callsign. Far lower than your band power limit, and easy to overlook.
- You must be able to shut it down within two hours of Ofcom asking. See the UK licence and images.
SSTV etiquette — FAQ
How long should I listen before transmitting SSTV?
Longer than you would for voice. A picture in progress can run for five minutes, and if you tune in during it you will hear tones with no callsign attached. Listen for at least one complete transmission cycle — three minutes is a reasonable minimum — before assuming a frequency is free.
How often should I send pictures?
Leave a clear gap after every transmission, long enough for someone to answer or break in. Back-to-back pictures with no pause turn a shared frequency into your personal broadcast, and other operators will simply go elsewhere.
Can anyone see the pictures I send?
Yes. Anyone with a receiver can decode them, including people with no connection to amateur radio — a cheap SDR and free software is all it takes. Send accordingly.
Are automated beacons acceptable?
In moderation and in the right place. An unattended beacon repeating pictures on a busy calling frequency is antisocial regardless of what the licence permits. Use a quieter frequency, leave generous intervals, and check your licence conditions for unattended operation.
More about Open Signal
See the frequency before you use it
Open Signal's live network shows which stations are on the air right now and what they are sending — so you can tell whether a frequency is busy before you commit five minutes to it.