4 Jun
2011
4 Jun
'11
7:59 p.m.
On Sat, Jun 4, 2011 at 4:57 PM, Charles Dickman
stated:
The local high school physics teacher was told to
clean out the lab of
Sigh, antique, indeed. I remember Electrical Measurements Lab with
wall galvanometers, bakelite and wood-box potentiometers, oil-bath
resistors, etc.
Heck, I spent several summers carrying around an L&N portable
potentiometer to calibrate chart recorders. Said potentiometer had a
Weston cell inside as well as a dry cell. You first set your
standard against the standard, then used your pocket thrermometer to
get the cold-junction temperature, then looked the thermocouple type
(Iron-constantan, chromel-alumel, or platinum-rhodium) up in a little
booklet and dialed in the corresonding voltage. 3 points or so for
each of hundreds of the things. You also took a bit of Windex with
you to clean the windows, a pen-cleaning wire, and a few No. 6 dry
cells (chart recorders also had Weston cells to calibrate against--
you looked at the position of the calibration slideware to see how
far gone the dry cell was) and a few silver slidewire contact beads.
It was a long hike back to the shop if you needed something else.
Most of the chart recorders were L&N Speedomax, with a few Micromax
and whole bunches of Honeywell/Brown Electronik units (tubes,
mechanical chopper amplifier).
Antiques, indeed. Good memories.
--Chuck
all the "old junk." She has a bunch of
meters that she is supposed to
dump, but she wanted to know if there was any market for "antique" >
meters. I have not seen them, but the way she describes them they are >
single function meters (galvanometers, AC voltmeter, DC voltmeter, >
etc.) in slope from cases with binding screw terminals
on top.