Guide Clearing pictures

Guide: clearing pictures in the weather and image modes

What it is. Image modes build a picture line by line while a signal arrives: weather satellites, weather fax, SSTV. When a new picture should start, or when you want a clean screen, you need to clear the old one. In 0.2.7 the clear buttons clear both what is on screen and what the decoder has collected, so the next picture really starts from scratch.

Which button in which mode

Mode	Button	What it does
Weather fax	clear picture (in the Fax view)	Clears the picture and the lines the decoder has collected, and starts a new picture at the next start tone or phasing. Pictures already in the list on the right stay.
Marine / weather fax	clear (top row of the mode)	Clears the NAVTEX and DSC lists, and the weather fax picture too when the Fax view is open.
Meteor-M LRPT	New picture	Starts a fresh image; use it at the start of a pass.
HRPT / AHRPT	New picture	The same for HRPT.
GOES HRIT	Clear	Empties the received products.
Elektro-L	Clear	Empties the received products.
SSTV	Clear	Clears the pictures the receiver keeps (also in the results file); the live picture stays hidden until the next one starts.
HamDRM	Clear	Clears the received items.
Any mode	Clear all (top bar, next to the version)	After a confirmation ("Are you sure? This clears all previous data and cannot be undone."), empties the decoded lists of every mode on every open receiver, including the weather fax picture. The saved copy on disk is emptied too.

Every mode also has a plain Clear or similar for its own lists. Decoded lists are kept through changes of mode, retunes and restarts until you clear them.

Step by step: a clean weather fax picture

1. Tune a weather fax station in Weather fax and start the receiver.
2. When a chart is finished and you want to start fresh, press save PNG first if you want to keep it (the button is disabled when there is no picture yet).
3. Press clear picture. The display empties and the decoder discards the lines it had; "waiting for the start tone" appears.
4. The next chart starts at the next start tone or phasing.

Step by step: a satellite pass

1. Before the pass, press New picture in Meteor-M LRPT (or HRPT).
2. During the pass the picture builds. Turn on Auto-save to save a PNG when no new lines have come for 90 seconds (the pass is over); Save PNG saves the picture as shown, at full size, into the mode's folder in the data folder.
3. After the pass press New picture again before the next one.

Tips

• Save before you clear; there is no undo for Clear all.
• Clearing a picture does not change settings, only the data.
• If you keep several pictures, use the mode's list or the Images window (View menu), which shows the pictures the receivers have decoded.
• In SSTV, "Save every picture" writes PNGs automatically by time and mode.

Troubleshooting

• The old picture comes back after a restart: results are kept until cleared; use Clear or Clear all.
• The new picture starts in the middle: weather fax waits for the start tone or phasing; a late start means the first lines are missing.
• Clear does nothing: the button needs a running receiver in some modes (for example New picture works only while it runs).

Related

Meteor-M LRPT | Weather fax | Tutorial: weather satellite images | Settings and files