Tech Note 299 Detail

Calibration Instructions for older Photogate Timers

Affected Products:

ME-9403 Digital Photogate Timer System

Problem/Symptom:
My older ME-9215/ME-9206 Photogate Timers appear to be out of calibration. How can I recalibrate them?

PASCO Solution:
  1. Remove the backside of the timer.
  2. Locate pin 3 of the 7555 timer (component U5, mounted opposite the access side) or probe the backside pins of U5 until you find an AC signal.
  3. Set the frequency on pin 3 of the 7555 to 10.00 kHz (+/-1%)by adjusting the 20 kOhm pot.
As an alternative, you can obtain a return authorization to have the units recalibrated at PASCO.

Creation Date: 11/12/2001
Last Modified: 04/11/2003
Mod Summary: