This segment is for commercial purchasers. D.I.Y. people can needless to say also apply much less, the same,
Office Ultimate 2007 Key hpcalc.org - HP48 Software Archive, far more,
Office Standard 2010 Sale, or variants. But individuals purchasing a conversion value a description of what is usually furnished. I also goal to provide specifically what the buyer needs or needs, not a prepackaged answer, so will not be afraid to request for that which you want. Description subject matter to change without recognize (usually bug fixes & enhancements etc).
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Here is a final update (I hope) regarding the malfunctioning power supply. A short recap:
My scanjet resets during scanning. After some searching I found out that the -12 v supply collapses during scanning causing a reset of the mother board via the orange power_good signal. Connecting power_good to a constant +5V signal reduced the problem to the display. My first assumption was that the capacitors involved in the -12v circuit were bad. Replacing them however did not solve the problem.
A closer look at the -12 v supply reveals that the voltage is stabilised using a KA 78R12 voltage regulator. This IC has a voltage disable pin (pin 4) which disables the output voltage. Pin4 is connected using an opto- couple to another circuit. After connecting pin 4 with a stable voltage the reset problem disappeared. Bingo! Conclusion the -12v supply was not the cause of the problem but was merely resetting as a consequence of another problem.
Following the opto coupler I found out that it was connected to pin 11 of KA3501. Pin 11 is the power good output signal of the +12 +5 v regulator.
This signal triggered the reset of both the -12 v circuit as the mainboard.
Measuring VCC at pin 7, I measured around 18 V. Then I saw a small trimmer (potmeter as we say in Holland) close to the KA 3501. Turning this trimmer clockwise I was able to increase the VCC to 20 V. After that the problem was over.
So my recommendation with similar powersupply issues is to measure the voltage at pin 7 of the KA 3501. If it is below 20 v. Try increasing it using the trimmer and check whether symptoms disappear.