Welch Allyn TM 262 Auto Tymp - User Manual - Manual (Page 34)

TM 262
2-16 Revised 4/11/08
Biological Check
The best way to determine that your instrument is operating properly is to perform a daily
check on a normal ear - your own ear if possible. This allows you to listen for the probe tone
and the stimulus tone (during reflex) and to determine if the air pressure system is working
properly. Keep a copy of your chart for a day-to-day reference in checking your instrument.
If you purchased the TM 262 with Audiometry, select the Audiometry (AUD) mode pushbutton
located in the center section of the front panel. Note that the display changes from the
tympanogram format to an Audiogram format. The < and > Hz buttons allow you to select each
frequency and the dB HL knob allows you to alter the intensity of each frequency. Position the
test headset on your head so that each earphone is covering the appropriate ear (i.e., red is right
and blue is left). Select the right earphone by pressing the front panel button labelled R and
check for the following while depressing the Present bar:
a. Depressing the < Hz button causes the frequency to change to a lower frequency;
depressing the > Hz button causes the frequency to change to a higher frequency.
b. Each frequency or tone is pure: i.e., there is no distortion or cracking sound present.
c. Rotating the dB HL knob in a clockwise direction causes the tone to increase
(become louder) in intensity; rotating the dB HL knob in a counterclockwise
direction causes the tone to become quieter (less intense).