FSR
MDC – MK1 Operations Manual [
Page 15 of 28
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SPECIFICATIONS ARE SUBJECT TO CHANGE WITHOUT NOTICE
6.2 Engineering
Items in this section will alter the basic operation of the Magellan MDC - MK1. The changes are generally
of a highly technical nature and should only be made when they are understood. Please read each item in
this section carefully before making any alterations.
When the Engineering message appears, press and hold both the + and - buttons simultaneously for
approximately 2 seconds, and then release both buttons.
Settings changed in this mode can be stored in Non Volatile Memory the same way as other settings.
ADC Ref. - input RGB level
The Magellan MDC - MK1 takes the analog signal destined for the computer monitor and converts it to a
digital signal in order to perform some signal processing and scan conversion. The actual device that
does this is an analogue to digital converter (ADC), and changing the upper reference level to this is
similar to a brightness control, but will also clip colors that are too bright to the maximum brightness level.
If this is incorrectly set then certain colors, such as yellow, may appear washed out, or even come out as
white. This adjustment is factory set and should not normally need altering.
§
It is highly recommended that this value is only adjusted when problems arise, and even then only
when a full color bar is displayed on the computer screen and an oscilloscope is connected to a video
output - thus allowing monitoring of the effects.
§
Pressing the + button increases the voltage at the ADC reference input (thus making the sampled
image darker, and reducing 'clip' effects), the - button decreases it (making the image brighter, but at
some point will start to 'clip' the RGB input).
§
The factory setting allows for an input up to 0.8v, thus allowing for out-of-tolerance RGB inputs.
DAC Ref. - output video level
The digital to analogue converter (DAC) changes the digital data output from the processing circuit into an
analog form that can be displayed on a standard video monitor or TV. Altering the reference level has an
effect similar to changing the contrast of the output signal.
§
It is highly recommended that this value is only adjusted when problems arise, and even then only
when a full color bar is displayed on the computer screen and an oscilloscope is connected to a video
output - thus allowing monitoring of the effects.
§
Pressing the + button increases the voltage at the DAC reference input, the - button decreases it.
CV Filter - for Composite Video
The MDC - MK1 allows some control over the amount of filtering on the Composite Video output. Altering
this may give a clearer image, or reduce dot-crawl.
§
In most circumstances, this should never need changing.
§
Pressing the + button increases the value thus applying more filtering, while the - button decreases it.
