Hi George,
I thought it would just make sense to preemptively replace the old original backup battery, as replacing it now would eliminate the burden of having to check up on the voltage in the months/years to come, not to mention some added peace of mind. Just my thinking. The battery that came with this unit SN 2137A04349 is a black "ETERNACELL", exact same as the one that came with the 3478A. I ordered a Panasonic replacement which will of course be bright yellow. BTW if you happen to know, how does one determine the year of manufacture of a 3468 based on the SN of the equipment? I assume the first 4 digits are the year and week, so if it is in any way similar to the SN of the classic calculators, the "21" needs to be added to some other figure to come up with the actual year. Most IC's on my board seem to have a 82-83 date code.
Any thoughts or suggestions of the corrosion on the LCD board connector pins?
On your generous parts offer, first of all many thanks, and I am certainly in no hurry, so unless something else comes along, waiting for your trip back to CO is more than ok with me.
Oh and BTW I always had a question about the ohms cal procedure of both the '78 and '68. Something I always wanted to ask since I first came across the verbatim in the manual several years ago when I got the 3478A. It states that ohms can only be calibrated in one of the modes (either 2 wire or 4 wire) but Not in BOTH? I am sure my interpretation its probably not entirely correct (it sounds so "un-HP") that the manual seems to suggest that for example one could never get accurate 4W measurements if the instrument was calibrated in 2W mode, or the other way around. But the added comment in the manual that states "Make sure the Multimeter is calibrated? in the [ohms] function in which it will be used" seems only make a stronger case for my interpretation.? Why can it not be calibrated in both ohms modes? Perhaps something to do with the initial 100-parts design limit? If anyone could shed some light on this issue, its certainly would be you!
Thanks.
Alex
