Stroke video is generated by a variety of random deflection devices. Examples include radar and sonar devices, spectrum analyzers, and Heads Up Display (HUD) generators. The Model SSC/220 Stroke-to-Raster Scan Converter Module converts stroke video from XYZ vector format to standard TV raster format. After conversion, the video can be recorded using standard TV cassette recorders and viewed using low cost, off-the-shelf TV monitors.

High quality video is generated by a combination of high frequency sampling and an advanced scaling algorithm. Scaling is an important consideration when converting computer-generated graphics or alpha numerics. Scaling on the SSC/220 is done using multitap FIR filtering and advanced horizontal and vertical interpolation to generate an 8-bit (256 level), high-resolution video signal. A selection of six different decay rates provides for emulation of a wide variety of stroke monitors.

The SSC/220 can accept signals in a stroke format, raster format, or a mixed stroke and raster format. Some stroke-generating devices have the ability to change the output signal between stroke and raster format in order to accommodate special display information. The SSC/220 can be adjusted to ensure that both the stroke and the raster data appear in their proper locations and intensities in the same output video signal.

To provide a common time base with an external video system, a genlock capability is included, which locks the [output] converted signal to either another video or composite sync signal. The SSC/220 also includes an internal test signal generator that can be used to either confirm proper operation or to provide fault isolation.