I am just about to sell my three Tascam units (144, 234, 414) on Ebay and have scanned and uploaded all documents associated with them. Feel free to wander around inside: http://www.mediafire.com/?5xdivf95pgb57
and download whatever takes your fancy. There is some info on a few other audio items apart from the Tascams, such as the dBx 117, and what I consider one of the most comprehensive and thorough reviews of mid-range microphones ever done (Mammoth Microphone Review). Not forgetting the best guide to multitrack recording ever written (TEAC Multitrack Primer).