Manual wanted for GNT 4604 Reader/Punch Station

I'm looking for a technical manual for a GNT model 4604 paper tape punch/reader. I have a scanned brochure which includes helpful information such as DIP switch settings, but I'd also like to find more detailed documentation, particularly including its handling of control characters and escape sequences, so that I can write a utility that talks to it. I can do basic I/O already, but I think it may have other features that I would like to use. If anybody can help me find an original, photocopy or scan, I'd appreciate that. For reference, I found the brochure here: http://www.cryptomuseum.com/telex/santec/gnt4606/files/gnt4604_brochure.pdf There are pictures of the very similar GNT 4606 here: http://www.cryptomuseum.com/telex/santec/gnt4606/index.htm I'll probably post about the machine on my web page eventually. -- Mark J. Blair, NF6X <nf6x at nf6x.net> http://www.nf6x.net/