Volgen ERK30-1515 change to 1212?

[staze]

All,

I recently picked up a Volgen ERK30-1515 (triple output, ±15V and +5V), and am wanting to change it on ±12V. I'm guessing it should just be a matter of swapping out some set resistors, but I haven't ever worked on SMPS's other than re-capping. Any thoughts on where I should start? I'll post a picture of the unit later today once I can open it up.

I have contacted the company, and they said these units were discontinued about 15 years ago, so they don't have any schematics available. =/