First post, by Benedikt
The FTL Sound Adapter is fully documented in the Dungeon Master Encyclopaedia. (See http://dmweb.free.fr/?q=node/1514, more photos at http://dmweb.free.fr/?q=node/622.)
And the Covox Speech Thing has been fully reverse engineered, as well. (Over in the CVX thread at CVX4 : high quality covox adapter – awesome job, folks!)
How much interest is there in somewhat more accurate replicas of these devices?
So far, I've created the following PCB layouts, one for an FTL Sound Adapter replica:
And one for a Speech Thing:
They would largely use the same components. The filter capacitor on the Speech Thing would be left unpopulated.
Furthermore, I've been able to identify all visible components on Cloudschatze's photo of the SoundJr (also in the CVX thread).
There's really nothing fancy on there, only a few resistors, diodes, PNP transistors and a big tantalum capacitor.
So with a bit of additional information that device is within reach, as well.
Any suggestions? What do you think?