Home |
Search |
Today's Posts |
#1
![]() |
|||
|
|||
![]()
Saw this at an antique shop today, couldn't for the life of me figure out
what it is. The label says Honeywell "Potentiometer", but it sure seems to look like more than that! "Standard Cell" as mentioned on the yellow tag in one of the photos is one of those calibrated battery cells that was talked about on RAR+P a while back, right? Just curious if anyone can tell me something about it. |
#2
![]() |
|||
|
|||
![]()
It is a temperature potentiometer. Good for making very precise temperature
measurements to check things. We often used a Leeds&Northrup before Fluke came out with the lower cost digital ones. A pain to use to make hundrends of measuremtns :-( Neil S. "Meat Plow" wrote in message ... On Sat, 01 Dec 2007 22:11:20 -0500, Buck Frobisher wrote: Saw this at an antique shop today, couldn't for the life of me figure out what it is. The label says Honeywell "Potentiometer", but it sure seems to look like more than that! "Standard Cell" as mentioned on the yellow tag in one of the photos is one of those calibrated battery cells that was talked about on RAR+P a while back, right? Just curious if anyone can tell me something about it. Tests the calibration of thermocouple devices in some kind of heating device maybe a lab furnace? |
#3
![]() |
|||
|
|||
![]()
On Sat, 1 Dec 2007 22:11:20 -0500, "Buck Frobisher"
wrote: Saw this at an antique shop today, couldn't for the life of me figure out what it is. The label says Honeywell "Potentiometer", but it sure seems to look like more than that! "Standard Cell" as mentioned on the yellow tag in one of the photos is one of those calibrated battery cells that was talked about on RAR+P a while back, right? Just curious if anyone can tell me something about it. Just a precision potentiometer to adjust the output voltage to an accurately known value, and allow comparison with an external (low) voltage that you need to accurately measure. Usually there is a battery votage source, and it is compared and standardised against the Standard cell, and adjusted so that the potentiometer settings read directly in volts. Then this can be used to compare with an external unknown supply by adjusting the potentiometer setting till the galvanometer reading is zero. The unknown voltage, and the potentiometer then are the same voltage, and you read the value directly off the scale. So it is basically used as an accurate voltmeter which has its own calibrator, and is high input impedance at the setting where the measurement is made. Usually used in the millivolts range, although High voltage units were also used. Peter Dettmann |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|