HELP! MFD Checker II

I just bought this <http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=25399&item=2507112537> off of E-bay. Obviously it's some kind of disk drive tester. I opened it up and the entire front panel is hand wired but I also found a commercail circuit board in it. On the board it says "MFD Checker II" "Sony" "Made in Japan". Does anyone know anything about a MFD checker? It looks as though the circuit board was once the major part of another machine and that they took the switches, displays and indicator lights off of it and rerouted them to the front panel. However there are a few things that they didn't put on the front panel; a 80 vs 70 track select (yeah 70 track), a drive select, a 300 vs 600 RPM select and a good number of test points such as the write gate. However on the front panel you can now select 2MHz, 1 MHz, 500kHz, 250kHz, 125kHz or 67.5kHz. Anybody know what that's about? I'm guessing that it controls the bit frequency that's written to the disk and that it's used to test the disk coercivity. On the original board you could only select 1F or 2F. I should add that a 2nd baord as also been added into the case. It's a handwrapped vector board with 20 SSI ICs. I'm sure that it's used to generate and select the extra frequencies and other as yet unknown functions. Anybody care to speculate? Joe