I have a portable test set by Data Disk Inc. of Sunnyvale CA that is identified as an "8000 Series Exerciser". It comes in a molded case with handle and removable lid that is 14"W x 10.5"D, and 7"H. It is powered from a fixed 3-conductor line cord by 115 +/- 10% VAC at 47-400Hz. The unit dates to late 1974 according to the panel information drawing taped to the inside of the lid. Also, users are enjoined to "be kind to this tester its a one & only" according to a label stuck onto the inside of the lid. It could well be as it is entirely wire wrapped. The panel contains several rows of mini-toggle switches to select tracks from 1-512, a 16-bit data pattern, modes of testing, power, etc. Also a four wheel indicating rotary switch to set bits/sector. External connections are a 50-conductor ribbon cable that is terminated in an edge connector (50-pin), and a row of banana jacks to permit bringing out 8 functions for scope display. It is available for the price of shipping to anyone who wants it. I'm guessing that it weighs about 10 pounds. - don