I am working with a SEM v12 which has been in service about 8 years. Output 1A recently went to a low level which we added an amp to compensate. All the inputs come in through the GigE ports 1 & 2. But now a bunch of inputs (not all) stopped working on the GigE 2 input. Input status on those shows no data.
Got another unit used, configured it the same and No inputs show data in. Can not get the Enet2 port to open and show data either. The front panel output lights have no green or red indications either.
Are there known common failures like this? Can the software be reprogrammed to possibly fix this?
The Sem V8 and V12 are EoL and EoS devices that have a rich history of input and output failures. These are hardware failures, not software. Typically a competent CATV repair shop can fix them but they will just fail again, and again, and again. I'd start looking for an APEX1000 to replace it, if you're not using ASI inputs - they're far more reliable. The only thing I dislike about apex is that, despite 4 gige input ports, they're shared backplane, so its really only 2gigs of input, so you can't even fully utilize all the outputs, but that aside, they're rock solid, at least, in my experience.
Thanks so much for that insight. We have swapped boards attempting to form some conclusions but not making progress. The boards have a lot of high-density flat pack chips. I would be very impressed by any shop that can determine which chips have failed. The main output heat-sinks get very hot. Power supplies appear to have no AC ripple - I think they are ok. What about finding a factory service manual, schematics, or block diagrams. The block diagram in the Install & Operation manual doesn't help much. If I knew which parts exactly we would replace and use the unit as much as possible. Thanks again.