A broadcast/studio workhorse whose value depends on head condition and on the firmware/board revision.
Tape deck: head wear (check the head face for a flat), capstan shaft and pinch roller condition, belt/idler kit and motor bearings decide the price; A77/B77 motor boards carry mains-derived voltages - never service with the case open and powered.
Marks that can be entered for this maker: Serial number, Model / catalogue number, British capacitor code (Hunts, Mullard), Japanese capacitor code (Nichicon, Chemi-Con, ELNA), EIA component code, Chassis / platter stamp, Version & era marker.
The introduction year is not documented, so the model narrows nothing.
Sold-price aggregates are not collected yet, so the archive gives no figure — condition, originality of the transformers and a documented recap move this model more than any list price.