Hi,
I have done a little more troubleshooting. I have found that the Fluke 192B/196B-C/199B-C Service manual contains some useful information.
I found that this section matches the same section on the R&S FSH3 SA:
If I measure the outputs on the 33174 Quad Op-amp, I got proportional voltages, but all of them were low. I measured the voltage on pin 4 of the 33174 it was also low around 5V instead of 30V.
The power supply on my FSH3 does NOT match the power supply that is documented in the Scopemeter manual:
(The schematic seems to match the power supply in Shahriar's FSH3).
I examined the board carefully, and I found a burnt resistor. I also measured 6 Ohms across two decoupling capacitors. I removed the capacitors, but the 6 Ohms remained. I removed a chip with a topmark 'LBHM'. A quick google search revealed that the chip is an LT3471.
Link:
http://www.linear.com/product/LT3471This chip is a Boost / Inverter in a 3 x 3mm DFN.
This could be used to generate the 30V needed by the LCD supply.
I have ordered the part from Digikey.
Regards,
Jay_Diddy_B