Bill, are you refering to the Serial to Paralell encoder converter for the D10A?
In any case, I am very sorry that you didn't get documentation for that. I just looked, and it appears that we don't have that documentation on-line yet. If you can send us a private message with a fax number, I can fax that to you first thing monday morning. I'll also make sure the documentation gets on-line quickly.
Also, can I assume you meant VAL Transponder? You only need one encoder in an aircraft unless you have multiple transpders and want redundancy.