Rohde Schwarz SML 02 RF Signal Generator repair

[hcglitte]

Hi,

I got a SML 02 sig gen which fails during calibration.
It fails at MULT-FILTER OPU3.
I have the service manuals, part 1 & 2. But no schematic.

Level preset also fails, but may be dependent on OPU3 multiplier filter.

It seems that OPU3 is used for higher frequencies only, hence using only lower frequencies may bypass it, if it is not fixable.

It does give RF out, but at wrong level.

Some lines at LCD, but that is OK.

Anyone who have experienced the same problem, or got some tips?