Waiting for HP54501A help

[miomao]

Gabriele (Florence, Italy). wrote:

Hello to everybody! Please help me!

I've bought an HP 54501A 100MHz digitizing oscilloscope, but it doesn't
work!

It seems to have a problem on the NON-VOLATILE RAM, so it doesn't pass the
self-tests.

Performing all the self-tests it gives 3 fails:

FAILED Protected non-volatile RAM TEST - 0000 0000 0000 0001
FAILED A/D TEST - 0000 0000 0111 1111
FAILED D/A TEST - 0000 0000 0000 1000

I think A/D and D/A fails depends on first fail, becouse CPU stores the
calibration information in this memory (this information comes from the
manuals).

Moreover, if I perform the self-calibration procedure (UTIL -> SERVICE
MENU -> CAL SELECT 3 -> START CAL), I obtain "cal ram write protected", even
if the rear calibration switch is set to UNPROTECTED mode.


Please help me! I'm looking for any information, particularly the
SCHEMATICS, the RAM position on the mainboard, the meaning of the previous
numbers, internet links, emails of
service centers, and so on...
I AM IN THE SAME IDENTICAL CONDITION. IS THERE SOMEONE WITH SUFFICENT EXPERIENCE TO HELP ME?
WELCOME ALSO THE ONLY SCHEMATIC!

Thank you,
miomao (romagna)

 

[davenn]

Hi miomao
welcome to the forums

have you looked online for the service manual ?
it is likely to give a list of reasons for the various fail messages


Dave

 

[CocaCola]

Please help me! I'm looking for any information, particularly the
SCHEMATICS, the RAM position on the mainboard, the meaning of the previous
numbers, internet links, emails of
service centers, and so on...

http://lmgtfy.com/?q=hp+54501a+manual

You will be amazed at what's on the first page of Google hits, I now know the likely reason the memory fails, what memory chips are used, a modern replacement, how to get the system up and running after a replacement and I just glanced at the first page of Google results...

 

[miomao]

http://lmgtfy.com/?q=hp+54501a+manual

You will be amazed at what's on the first page of Google hits, I now know the likely reason the memory fails, what memory chips are used, a modern replacement, how to get the system up and running after a replacement and I just glanced at the first page of Google results...

HI CocaCola,
Thanks for your reply, but I have TONS of manuals, programming, commands front panel ecc. ecc.
I am searching only for the schematic, but nothing to do, nobody has the schematics of HP54501A !!! For my fortune I found how I need. Substantially I have a 54501 with a defect (see my first post). I found on the web an easy tutorial to repair it, when there is the same condition. For you and for all the members of this forum I put the link:
http://www.radiocollection.be/uk/HP54503_uk.html

Well, so long
miomao