I had another look with the scope, I couldn't see anything.
Looking at the voltage drop across the 10R in the PSU filters, its about 850 mV, which means ~85mA (+/- 5%). The calculated current with the BW pin connected to Vee (as it is in my case) is 80mA, not taking the worst case values from the datasheet. I've got an NEC relay in there that draws 10mA more than the Axicom, I had about 20 that I bought to build a switched attenuator.
The hottest things are the 49990s, but they're not finger-pull-away hot which probably means they're no hotter than 50 degrees C, and they take a while to get there, there's not a lot of cooling available to them.
It would be nice to get a 500M scope on there, I wonder if the university would give me 5 minutes.
Edit:- corrected slip of the pen from 10% to 5%
Edited by wakibaki - 7/3/12 at 11:36am