Racal-Dana 5004 multimeter - dead display - need manual

[psykok]

Hi,

I scored recently a nice Racal-Dana 5004 multimeter.
Appart from the missing covers, the instrument looks in very good shape.

I received it today and after a quick check, it looks like that nothing get displayed on the front panel.


I was wondering if someone is owning the service manual fro this multimeter?


Alex

[autotel]

I sought for it on Ebay, and interestingly I found that some people sell the manual, in CD format. What if you can find it for download? Also remember to search in the internet archive (archive.org), where you can usually find the more obscure stuff. I hope you find it!

[psykok]

I have not found the documentation for the 5004, but the one for the 5005 is available here:
http://ftb.ko4bb.com/manuals/198.21.21.21/Racal_5005-5006_Digital_Multimeter_Service_Manual_1981.pdf

Fortunately the 5004 share apparently a lot with the 5005.
I think it will be good enough for a start.

After a quick check I found a missing component in the voltage reference area.
Originally component (AR3) was a AD542.

I replaced it with a LF536. After this operation the multimeter was not giving more signs of life.

I check the temperature on thee ICs close to the OPA I replace and I almost burned my finger on U11.
Apparently the dumb ass who did some repairs on this unit did install U11 in the wrong way . After a closer check, same for U10.

Figers crossed, I turned the unit on  .... magic it works again, or at least it's displaying something and oing a boot sequence.