HP2748A papertape reader : connector ?

Bob Shannon wrote... the HP Bob is incorrect for the 2100 as well as the entire 21MX M/E/F (and HP1000) lines. He could very well be right on the 2114/5/6 cpu's though. The HP 2748B paper tape readers were connected to an HP2100 or HP21MX M/E/F system via the 8-bit duplex register board. No other interface was used, at least for sale in HP configurations. Matter of fact, if you bought the paper tape reader kit (the part # escapes my mind) which included the paper tape reader, the HOST interface board, cables, manuals, and diagnostic, there was only one interface you would ever get. The 8-bit duplex register. This was the HP designated interface for the 2748B. I can only assume Bob is referring to the older 2114 (not actually an HP machine other than the label), 2115, and 2116 machines which I'm not as familiar with. I have however, seen 2748B paper tape readers hooked up to a 2116 with an 8 bit duplex register so I know that to say in general terms that the HP tape reader board is unique and not the 8 bit duplex register board isn't accurate. But I can't speak from experience on the 2114 or 2115. Of course, the 2114/5/6 are NOT 2100 machines, and of course they're not 21MX M/E/F systems either. So, perhaps early 2114/5/6's had a modified paper tape reader and a unique interface at that time, but certainly not after the 2116. Jay West