I just recently bought a Viewsonic N4 to overcome my inability to display my Commodore machines on LCD monitors. This unit came without a power supply (basic wall wart, 12V at 1.2A) The problem is I cannot find a replacement(Viewsonic claims the device doesn't exist) and there is nowhere I can find whether the connector is center positive or negative. Does anyone out there have a N4 and can tell me? Or is there some website that might have the info I need? -Thanks

Welcome!


Of the two terminals on the power connector, the one which is negative will almost certainly connect to the device's internal ground -- and thereby to the Ground pins on the VGA connector (and the grounds on any other signal connectors on the device). If I were in your situation I would simply do a continuity test. If the center terminal connects to VGA ground then center is negative. If the outer "barrel" terminal connects to VGA ground then barrel is negative.

I don't have access to N4 documentation -- and until today I never heard of the N4! -- but if anyone else posts on the subject then maybe we can verify with a second opinion!

cheers,
Jeff

Edit: I found an image, and I notice there are lots of signal connectors. It'll be easy to access ground on the RF or RCA connectors! BTW, are you sure they haven't hidden a polarity indication somewhere? Just checking.

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