Agilent N1996A repair

[stan_cool]

I just purchased Agilent N1996A on ebay, listed for repair. Upon inspection I found that one of the 3 boards inside is missing, that is N1996-60003 power supply board. After purchasing the board separately and reinstalling it the unit now turns on, but the screen is absolutely black and the unit makes no sound. However the fan is running and I can see the unit is taking about 0.5A of current.

I am wondering, what would be the steps to troubleshoot?

1) Is there any console/debug port that I can hook up to and see the actual linux booting?
2) Maybe if the problem is just in the screen I could send some GPIB commands and verify it that way?

Anything helps!

[TheSteve]

The N1996A doesn't have GPIB. If it is alive you should be able to connect it to your lan and it should grab an IP address. It should answer telnet requests.
I think I still have a spare CPU board for an N1996A that has a small flaw but does boot up and work.

[stan_cool]

Thank you so much for the reply!

I am wondering if the PSU board is also a CPU board actually?

Everywhere it says it's a PSU board but upon close examination it seems that the second board (sandwiched on top) is actually a digital board with some memory chips (and what looks like a PCMCIA card). Is the actual CPU on the second board or is it in the PCMCIA card that I am missing?

[TheSteve]

The smaller daughter board is the actual processor unit. The PCMCIA slot was only used for recovery if the internal flash became corrupted and is normally empty.
I assume the blue cable was connected when you had the card installed.

[stan_cool]

Thanks, yeah, the blue cable is connected.

Update: I was able to telnet into my unit and verify all the usual locations for the software (see other threads) and the options inside of the elgato.lic file. Also connected to the unit from the Keysight Connection Expert and sent a couple of commands. At this point I am sure the unit is at least working, so I am narrowing down my repairs to the screen area.

The screen is Mitsubishi AA084XA03, 8.4" 6/8 bit LVDS screen, readily available on the ebay.

[TheSteve]

Did you verify its not a dead backlight in the LCD?