Digital format converters

I know you guys mostly hack on analog fun stuff, but I've seen some digital knowledge seeping about here and there...

I'd really like to build a format converter that goes betwixt TDIF and ADAT... I've needed at least one, maybe more, for a long time now, and they are getting scarcer and more expensive. I almost had an apogee FC-8 on ebay for a hunnert bucks, and it got sniped away at the last second

What all is involved with these things, and how difficult would it be to DIY?

I drew a PCB for one some time ago - it's not difficult at all. I found the schematic: http://stiftsbogtrykkeriet.dk/~mcs/OptoGen.gif
And PCB layout: http://stiftsbogtrykkeriet.dk/~mcs/OptoGen_pcb.gif

Nobody has tested it yet (I think). I don't have the hardware to test it, but the schematic is straight from the datasheet, so it should work.

Best regards,

Mikkel C. Simonsen

I already made tests with the al1401 and with success (only stuff only ADAT convertor that is working).
I think Mcs schematic and pcb is better than mine which can be found here :
http://membres.lycos.fr/blendinpulse/adat/

So the ADAT stuff is relatively open...

What about TDIF? Anyone know anything about how it works?