R&S FSU spectrum analyzer, defective 1st Mixer, help needed

[decker172]

Hello,

i have a defective rohde and schwarz spectrum analyzer FSU. The input mixer, located on the RF CONVERTER BOARD (part 1130.4001) is defective. I need a replacement but i dont know much about this part. Find attached some pictures.

RF 20Hz..3.6GHz
LO 4628MHz..8128MHz

Has someone the schematics or a part list of the RF CONVERTER BOARD (part 1130.4001). Or maybe for the other variants of this board  1130.1990, 1130.4047 and 1130.4647? Can someone help me finding a suitable replacement.

Thanks in Advance.

Best Regards
Decker