• An Impulse Map is an audio-file, which can be radio transmitted. It gets converted from a bitmap (raster graphics) and the receiver of the signal can make the map visible by using a so-called waterfall display.
• Use either the text input field to generate a bitmap to convert OR use the file uploader to upload a bitmap to convert. Uploaded bitmaps must be max. 120kB, 10 - 100px width and 24bit RGB in BMP format.
• An Impulse Map can only be sent on longitudinal operation modes. This is Single Side Band an in principal Amplitude Modulation, but that would mirror the map, which is mostly undesired. This converter is made for waterfalls which run downwards (as waterfall implies). You still can use it for upward waterfalls, when you convert for the lower side band but send the result on the upper side band and vice versa.
• The Sample Rate is the rate of the resulting audio file. Keep it as low as your hardware allows but at least twice the bandwidth you use.
• The Bandwidth is the base-band spectrum on which the Impulse Map will be visible. Keep it according to the respective band's specification. When uploading bitmaps, keep in mind, that a too wide bitmap on a too narrow bandwidth will lead to bad results. As a general rule, the bandwidth devided by the width of the bitmap should at be around 100.
• The Frequency Shift will shift the whole signal to the right (left on lower side band). This is to respect low cuts. If you use e.g. 2400Hz bandwidth and 300Hz shift, your Impulse Map will be present from 300Hz to 2700Hz.
• The Sustain is the speed of the Impulse Map. Rather the time each row of the map is sent until the next row is sent. The higher the sustain the slower the signal.
• The number of oscillators equals the number of horizontal pixels in the bitmap (always auto).
• It is mostly wise to not send straight horizontal lines to the spectrum. This is because most transmitters will smudge the signal's ends, when it is rather broad. When using an oblique font, there are hardly any horizontal lines, which results mostly in a clearer appearance.
• Fonts as a whole need more space than single characters will. E.g. "T" and "j" - the first needs some space above the second some below. So, when using narrow bandwidths, it can be wise to only use upper-case letters, in order to utilize the maximum available bandwidth.
© Stheleris c/o openpot Media
The author of this software is not responsible for the use of any data generated by this software. Specifically not for any use on radio frequencies, which violates established law. Not the author but the user of this software is responsible to respect laws and regulations, specially in regard to allowed operation modes and bandwidth on the relevant frequencies.
Furthermore, the author of this software is not responsible for any damage which could result from the intended or not intended use of this software and the thereby generated data. Especially not for damages on technical equipment, data loss or bodily damage. USE THIS SOFTWARE AT YOUR OWN RISK!
The use of this software is free and the data thereby generated can be used for any purpose, including modification, publishing, selling in private and commercial contexts.
This site does not use cookies. The server hosting this site, logs user access with IP address, browser, operating system and referer, if any. As long as you do not re-load this page, your generated Impulse Maps get overwritten every time you generate a new one. If you do not want to leave any of your generated data on this server, simple generate a last one with a dummy text. Still, we will delete generated data from time to time.
Stheleris
c/o openpot Media e.K.
Lauterbadstr. 31
D-72250 Freudenstadt
Germany
bureau (at) stheleris (dot) com