Here's what I'm planning to do to the RF AM stabilizer box. I'm going to take out several of the components along the path to the EOM (comments in green), including the dead ERA-4 and ERA-5 amplifiers, the variable attenuator which is controlled by a switch that can't be accessed outside the box, and the feedback path from the daughter board servo. I'm arranging things so that the output of the HELA-10 does not exceed the maximum output power. 

I wasn't quite as sure what to do about the path to the ASC box (comments in blue). I talked with Gautam and he said this gets split equally between several singals, one of which goes to the LO of the demod board which expects -10 dBm and currently gets -12 dBm (can go up to -8 by turning switch). So maybe we don't actually want the signal to be anywhere near +27 dBm at the output. The plans for the box are here, it looks like +27 in will end up with +10 at each output, which is way more than what's currently coming out. But maybe this needs to be increased to match the other path? 

Also we haven't measured the actual response of the variable attenuator U4 for various switch positions; it's the same model as the one I'm removing from the EOM path and that one had slightly different behavior for different switch positions than what the spec sheet says. Same goes for the HELA-10 units along this path: what is their actual gain? So perhaps these should be measured and then a single attenuator should be chosen to get the right output signal level. Alternatively it could just be left alone, if it is at an OK level right now. Advice on what to do here would be appreciated.  

I'll work on the EOM path tonight and wait for feedback on the rest of it. 

EDIT: Gautam pointed out that there's some insertion loss from the components I'll be removing that hasn't been accounted for. Also the plans have been updated to reflect that I'm replacing AT5 with a 1dB attenuator (from 6 dB).