Issues about SMU200A repairing

[Dynamix]

Hi,
My SMU200A generator can't properly power up these days. The green LED is on after pushing the power button, but the screen doesn't show up. Does anybody have a clue about it?
I have found the service manual for a long time but found nothing besides the operation manual . Does anybody have a service manual?
Thanks!

[DaJMasta]

Not exactly the right forum for it, but I can maybe point you in a reasonable direction from working on some similar vintage R&S stuff.

It's a windows based unit and the motherboard is under the screen unit, you'd need to take off the front faceplate, then remove the screen/keypad to get at it, though the hard drive is actually in the body of it (comes off with screws in the back feet).

Is the instrument booting?  Can you get any output on the rear VGA connector?  Do you hear any relay clicks from alignment if you wait a while for it to start?


Could be that the screen backlight is dead or the screen cable is unplugged. could be that the mainboard is bricked, could be something else.  If it was just an OS/hard drive issue then you'd probably at least get the bios screen on the front panel.  If nothing's turning on, maybe the cable to the front panel has been slightly unseated (the lights and power button still go through it, though), could be power supply related with the rest of the instrument.


Not a lot of detail to go on and it's modern enough that you shouldn't expect a service manual any time soon - R&S may still be able to happily service it for you for a few grand....

[Qw3rtzuiop]

Hello,
there is a service manual avaiable. You need a Rohde & Schwarz Gloris account to get access to it.
https://gloris.rohde-schwarz.com/anonymous/en/pages/toplevel/home.html?

The easiest problem could be a broken screen backlight. If i remember correctly it still uses a ccfl backlight. They are likely to fail. The service manual advises to measure the mainboard voltages if the green light turns on but the screen remains dark.