Repair Complete
Restoration and Repair Completed
Wang 600 Bad Parts
After a long journey and some puzzling symptoms, Wang 600 CC-2001 is restored and fully repaired.
A significant number of defects were found including the marked tendency of Fairchild 9946 DTL ICs to fail, five of these requiring replacement.
The Wire Braid ROM has three dead addresses and repair is not feasible. The machine is running well with an EPROM-based ROM emulator and this also offers ready availability of diagnostic microcode routines if failures occur in future.
Wang 600 In Use
The machine is generally nice to use, the fan is only mildly noisy. The printer drum tends to rub noisily on the paper whenever the printer is on, and it’s quite loud when clacking out a line of print.
The keyboard is easy to use but it’s not too hard to beat the machine with rapid keystrokes. Calculations feel pretty much instantaneous. The user interface is a little arcane but once learned is pretty efficient. The range of inbuilt functions is pretty good and in particular it is very helpful to have trig functions inbuilt, rather than having to load from a software library as for the 700 series.
The tape drive can be a bit off-putting because the bit density is pretty high for the amount of data typically recorded. The Lunar Lander program of 200 or so lines takes only 2-3 seconds to store or load, it’s so quick that at first one thinks the load or store has commenced and then crashed. The first part of a casette gets quite a bit of work as a result but this can be used to advantage if the tape is worn - simply open the cassette and trim 50cm or so from each end of the tape to expose tape that has been barely used.
Lunar Lander
No self-respecting early 70s owner of a programmable calculator would not have played Lunar Lander.
A not-too-bad version that tracks vehicle mass as fuel is consumed can be coded in 150 or so instructions, including code to provide a running commentary on the printer or an attached IBM typewriter. The single line display is a bit limiting and the Wang 700 version is nicer with separate lines to display altitude and velocity.