New finds: HP9825 etc.

Upon the date 12:11 PM 8/5/00 -0500, Joe said something like: -- snip -- That's right Joe, on points you make above. The chiclet kbrd was a right pain. On our first 9825A that was purchased for use on a production machine, the 'Continue' key collapsed after quite a few operations. The operator hit that key at least once for linear encoder that was calibrated on that machine. Usually 100-200 encoders per day, five or six days per week, for about three years before that switch gave out. Typically, like our Tony Duell, I set to finding out if I could fix it. Also, production was shut down because of this so there was a second, more important reason ;-) I dismantled the keyboard to pieces and carefully setup the flat spring's curve and soldered the contact to at least temporarily fix it. Back into production. I promptly ordered a replacement keyboard from HP (for $350 as I recall) and received a kit containing a new upper front case section which has the fastening mounts for the display, tape drive and printer and of course the keyboard plus a nice Cherry keyboard. The badge on front said 9825B indicating the case section was simply pulled from the then-built B's inventory to make the retrofit kits. The operators were literally thrilled over the better keystroke action as they had to type serial numbers of the encoder under test plus occasionally other notes for each calibration run. I still have that repaired keyboard plus I eventually ended up with that old 9825"B", nee A. I also eventually got our second 9825T which we put on a second machine that myself and a couple of other engineers built plus all docs, peripherals, accessories, etc. :-) However, during a production day, that old "A" developed a shorted series-pass transistor in its switching PSU board which put ~+18 volts onto the +5 V supply bus. Well, you know what happened next. I recall very well the HP Service Manager down at the old Paramus, NJ Service Center grousing that this happened occasionally and that those %$@*)! designers did not put in a crowbar circuit or other protection to prevent smoking the whole machine. Over $2000 worth of replacement assemblies caused the machine to be junked by the company (no way was it worth it as we had just one calibration machine using a 9825, the other had been 'updated' to one of those new-fangled Zenith Z150 peecees and I could find used 9825T's at that time (~1991) for $1500-$1800). My car became the 'dumpster'. Regarding the comment by someone in this thread (at 8:08 AM, 3 Aug as shown above), what makes the replacement kybd so horrible? Could that have been an early version of a replacement before the Cherry's were used? Regards, Chris -- -- Christian Fandt, Electronic/Electrical Historian Jamestown, NY USA cfandt(a)netsync.net Member of Antique Wireless Association URL: http://www.antiquewireless.org/