I believe I saw a system with the option interface card for pc admin. It was an option card that provided 2 station ports, one could be a door phone. It had a 9 pin serial connector on it. The option board was bad and replaced. Not knowing what was wrong before going on site - and assuming it was a power supply I looked for what we had back at the shop. The Omega 924 uses a 30v 4 amp power supply I believe, not so common. I found an old HP laptop (I think) power supply that output 32v and something like .975 amps. Was very surprised to see it ran our spare system with 2 phones (of course had to change the connector). Probably a few more phones would be too much, or maybe over time it would fail. Kept it aside just in case. Fortunately we were able to purchase a few spares.

I'm never worked on small systems like this until recently, but I'm impressed with the capabilities of the system. It has several features that large PBXs capable of hundreds or even thousands of lines just didn't have. I heard it never really took off, seems like a great small system.