Ok... I tried to do this myself, but it turns out I need some help.
I just went downstairs to pull apart my VT103 and my VT100 to do a side-by-side against your concept. Much to my embarrassment, I now realize I have two VT103s and no VT100.
The supplies for the VT100 and the VT103 are the H7831 and H7835, respectively.
Output specs for each are:
H7831 (VT100)
- +5@1.5A min to 11.0A max
- +12@1.0A min to 2.75A max
- -12@0.0A min to 0.5A max
- -23@0.01A
H7835 (VT103)
- +5@16.0A
- +12@5.0A
- -12@0.5A
- -23@0.01A
- BPOK
- BDCOK
- LTC
Form factor appears very similar, as one would expect being in the same terminal case. Both units have the same VT100 boards to contend with.
However, the VT103 also has a fan that is obviously powered somehow and a QBUS backplane. Models with the TU58 have it powered by separate connector from the backplane.
I believe the cables are the main interconnect difference but the supply end may be compatible. I do note however that positions for A thru V on the main supply connector are physically swapped in the drawings of the two units. The VT103 supply also has a socket to receive an additional board (H786) which creates the BPOK, BDCOK and LTC signals. This board plugs into the H7835. Cabling for those signals must be conducted via the main connector and cabling.
So, while I can co-operate with someone to check if your project can be done to be compatible with both, I can't easily do both ends without relying solely on my interpretation of the schematics, which I am reticent to do.
I'll be happy to document the VT103 here online in photos so we can do a comparison and answer this question before finalizing your order, but I'll need someone else to do the VT100 side. (Unless someone in my area has one I can document?)
My sense is that pins on the supply's output connector are indeed assigned upwardly compatible, and that your design could accommodate the needs of both VT100 and VT103 supplies by including artwork for the connector to receive the H786. (or by including logic to do that function without the H786)
It would be a shame to miss the opportunity if it exists, as the ATX supply can easily provide power sufficient for both needs.
It's kinda late to do all that tonight. Please post if I should go ahead, and I'll check back. This delay may provide time for a VT100 rendezvous to surface too.