
Echometer Company
Model – M Manual
Phone: (940) 767-4334
5001 Ditto Lane
Page
36
Fax: (940) 723-7507
Wichita Falls, Texas 76302, U.S.A.
E-Mail:Amplifiers And Filters Test
On Model M Recorders having serial numbers above 5100, the amplifiers and filters are checked automatically. After the
power switch is turned on and the test has been performed, the message PASS or FAIL is recorded onto the strip chart. On
units below serial number 5100, the amplifiers and filters are checked each time that the POWER switch is turned ON. The
UPPER COLLARS filter is checked if the filter switch is in the UPPER COLLARS position. The LOWER COLLARS
filter is checked if the filter switch is in the LOWER COLLARS position. Internally, an electrical pulse is applied to the
input of the electronics so that the amplifiers, filters, microprocessor, battery, printhead and chart drive are tested. The test
patterns displayed below are recorded if the battery and electronics are operating properly. The positions of the gain
controls do not affect the recorded test patterns. The battery voltage is also displayed. Refer to Section 7 for information
on proper battery voltage. The battery must be charged sufficiently to power the red LED light beside the power switch, the
electronics and the chart drive motor. If the red LED does not light, the battery must be recharged or the 12-volt external
power cord must be used before a proper test can be performed on the electronics system.
UPPER
COLLARS
FILTER
TEST
LIQUID
LEVEL
FILTER
TEST
LOWER
COLLAR
FILTER
TEST
LIQUID
LEVEL
FILTER
TEST