Top critical review
13 people found this helpful
Why dynex dx-cvs4 may not work for you and how to fix it
on February 28, 2012
I bought one of these new and out of the box it didn't work. It would switch audio as it should but the video was black for all sources.
I messed with it for a while and finally decided to take it apart to see if I could figure out why it didn't work.
Being an electronics engineer, the answer was simple- each video input jack has a 75 ohm resistor hooked from the input to ground.
This resistor, although technically correct, loads down many "real world" video sources to the point that they are too weak to provide a viable signal= black screen.
The fix was to heat up a soldering iron and remove them all. They are the ones on the under side of the circuit board nearest to VIDEO INPUT JACKS ONLY marked "750" (There are some "473" resistors on the audio lines, leave them alone,
and there are also some "750" resistors on the output jacks, leave them alone also!)
Once I removed the resistors and put it back together, it works perfectly.
My guess is that for those who write good reviews for this unit, their video sources are more robust than many standard consumer devices and the resistors don't adversely affect them.
But many video sources are not so robust, and for those people who write reviews reporting black screens, poor or otherwise distorted video, etc, this is likely the problem.
Too bad, Dynex, you have a great product but due to lack of homework there are a lot of people who will be disappointed. Probably why you can find these things dirt cheap everywhere!