Looking for a GraphOn 235 keyboard

Hi, I have this GraphOn 235 next to me that arrived some time ago without a keyboard. It appears to take a handset jack (_not_ an RJ11, but similar), so unless it _happens_ to be compatible with an LK201-type keyboard, I'd have nothing to go on it. I've been googling on it, but not finding any technical docs, only "how to use" instructions for various universities. I _know_ it emulates a Tek 4014 (among other things), so docs of that nature aren't getting me anywhere. Anyone have any hard technical docs on something like this, or at least know something about its keyboard? Internally, it's driven by a 68000, but without disassembling the ROMs and reverse-engineering the memory map, I can't tell much about how it works. Thanks for any pointers, -ethan