gar
Senior Member
- Location
- Ann Arbor, Michigan
- Occupation
- EE
221105-2140 EDT
i have a Simpson Model 389 thermistor temperature meter that I purchased in 1961. This still works and is quite accurate.
This evening I ran a test on it. Note: this is somewhat 62 years later. Their major calibration point is 32 degrees F, freezing point of water. So I created an ice bath, and the temperature read exactly 32 degrees. Very good.
The meter has two ranges, -50 F to 100 F, and 100 F to 250 F. So I adjusted a water bath ( small jar of tap water ) so that the meter read 100 F. on the low range, Then with little time difference switched to the high range, and the reading was within 1 F, reading 101 F. However, there is a much greater reading error if the meter is at some other angle than its optimum angle.
The meter has two externally accessible calibration adjustments. One is called CAL and the other ADJ. Neither has been adjusted since the meter was bought.
.
i have a Simpson Model 389 thermistor temperature meter that I purchased in 1961. This still works and is quite accurate.
This evening I ran a test on it. Note: this is somewhat 62 years later. Their major calibration point is 32 degrees F, freezing point of water. So I created an ice bath, and the temperature read exactly 32 degrees. Very good.
The meter has two ranges, -50 F to 100 F, and 100 F to 250 F. So I adjusted a water bath ( small jar of tap water ) so that the meter read 100 F. on the low range, Then with little time difference switched to the high range, and the reading was within 1 F, reading 101 F. However, there is a much greater reading error if the meter is at some other angle than its optimum angle.
The meter has two externally accessible calibration adjustments. One is called CAL and the other ADJ. Neither has been adjusted since the meter was bought.
.