Help › Operating

Sending and receiving SSTV

The console's SSTV panel receives and sends slow-scan television: still pictures sent as audio, a line at a time. It works on your device, from the radio's receive audio and through its transmit audio, with nothing to install. It's on every plan.

Open the panel

Put the radio in LSB or USB with DATA on. A panel for digital modes opens under the mode buttons.
Click SSTV in the row of buttons above it.
Choose a band from Go to band… to tune where SSTV is usually found and switch to that band's sideband with DATA on: 3.845 and 7.171 MHz (LSB), 14.230, 21.340, 28.680 and 50.680 MHz (USB). 14.230 MHz is the busiest.

Receiving

Receive audio must be on in the console. The panel hears what you hear.
Leave Receive ticked. Each picture starts with a code (VIS) that names its mode, so the panel picks the mode by itself and draws the picture line by line as it arrives. Under it, the panel shows the mode and how many lines have come in.
A sender's sound card is never exactly on time, which would slant the picture. The panel follows the sync pulse at each line and corrects for it, and when the picture ends it draws the whole picture again with the final timing, so the first lines straighten too.
Tuned in late and missed the start? Choose the mode under Missed the start? and click Start now. The panel finds where the lines begin by itself; the picture starts from the line it caught.
Stop ends a picture early and keeps what arrived. A picture also ends on its own if the signal goes for several lines.
Received pictures appear in a row under the screen; click one to look at it again. Save downloads it as a PNG. They're kept until you leave or reload the page, the last 12 of them.

Pictures come through cleanly with a signal about 10 dB over the noise (in a 2500 Hz SSB filter). Weaker ones arrive speckled; at about 7 dB they're rough but recognizable, and the start code may be missed (use Start now). Robot and PD pictures carry color as differences, which noise shows more.

Sending

The bottom of the panel shows the picture you'll send, at the mode's size:

Mode: Scottie 1 is the most used in North America, Martin 1 in Europe; PD 120 and PD 180 send bigger pictures (640 by 496) more slowly. Each mode shows how long it takes to send, from 36 seconds (Robot 36) to over 4 minutes (Scottie DX). The station's transmit time limit (3 minutes unless it's been changed) would cut PD 180, PD 240 and Scottie DX off partway, so they're marked over the time limit and can't be sent.
Choose picture… picks a picture from this device. It's cropped to fill the frame, keeping the middle. Without one, the panel sends a test card: color bars over a gray ramp. Send back under a received picture sends that one (a common reply). Use the test card goes back to the bars.
The two lines of text go at the top and bottom of the picture. {MY} is your callsign and {CALL} the call in Their call, so {CALL} DE {MY} 595 puts a report on a reply. The panel remembers the lines and mode on this device.
Click Send. The radio transmits for the whole picture, and the panel counts the time. Stop (or Esc) ends it and unkeys.

Sending needs the radio in LSB or USB with DATA on, so the picture's tones go out as audio; the panel offers to switch. On a radio connected over the network, its DATA MOD setting must be LAN (see Network radios). Set the transmit power and audio level as you would for other data modes: SSTV is a full-power signal for the whole picture, so a long mode at full power works the amplifier and radio hard. Your own transmission isn't decoded.

Not built yet: modes other than those listed, sending from a camera, and keeping received pictures between visits.