Fluke 8840A/AF Mysterious parts, Need help.

[sampler1]

Hi Folks,
I purchased an 8840A/AF. When I turn it on it cycles on and off with the relay clicking. First thing I did was to check the voltage rails and they all seem ok with the exception of the
-8.2Volt rail. It reads 5.2volts. I ended up checking everything from the Bridge to the test points in that section and all was good. Two mysterious  discoveries were made..
R601 is supposed to be 560 ohms and it had a factory installed 1 kilohm resistor? Next I discovered I cannot find anywhere  CR617 (8.2v zener)?? I have searched Hi and low and it does not seem to be in the circuit, in fact it is not even listed on the parts location??
ANY Ideas?

I am also trying to figure where this -8.2 volt rail goes and where it is used.

Any help would be appreciated.

I have verified all the capacitors, zener diodes, (except CR617), replaced the regulators, resistors in the section of TP603,604,605,606.
I realize most was not necessary because the parts were ok.

Help Help ( the manual can be found all over the net , it includes schematics)
Garry

[bob91343]

I found R602 which is connected to the 'missing' zener.

They must have changed the unit somehow.

[coromonadalix]

Maybe some typo errors in the service manual or the pcp prints ??

I see some -7 volts on the pca board, figure 9-3   but not in the psu section, surely  typo mistakes

manual taken from there:
https://www.artisantg.com/info/PDF__466C756B655F38383430415F4D616E75616C.pdf

This artisantg manual is incomplete

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On ko4bb

there is an -8.2v going into the pca section a/d  pin 17,  figure 10-2

manual from there
http://www.ko4bb.com/manuals/45.78.238.75/Fluke_8840A_schematic_sheet2_ADC.pdf

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Since the 8842 is similar,    check the table 6-22  it tells you where the -8.2v are going, it goes to u303 and u304

http://www.ko4bb.com/manuals/45.78.238.75/Fluke_8842A_Digital_multimeter_Service_Manual.pdf



It depend wich schematic source you use  loll

[sampler1]

I found out  the missing Zener is not used and the resistor was changed to 1k.
the -8.2v is going to u303 and u304.

Figure 10-2 is a hacked copy of the real 8840 manual 

Thanks for the info guys..