Semi-OT: Need help identifying diode specs

I picked up a few spare diodes from my local surplus place, and I need some help identifying them.. They're about 3-3/4" long and 1-1/4" wide at the (hex) mounting base, have a threaded negative terminal, and an approx 1/2" diameter positive terminal on the top. They appear to have a Westinghouse (underlined W in a circle) logo on them, next to a diode symbol marking polarity. Next to that is the number "18840100" (part number?) and "8206" (date code?). Any idea what voltage and amperage this diode should be rated for? I tried googling for info, but only found a few places that wanted to sell me one (with at best the info that it's a "semiconductor diode".. gee, thanks). One site also listed the part number "5961-01-198-6175" as an equivalent. Thanks much, Pat -- Purdue University Research Computing --- http://www.rcac.purdue.edu/ The Computer Refuge --- http://computer-refuge.org