19
915-BL Dual Frequency Doppler
Maintenance and Service
Troubleshooting Guide
This table lists common problems and suggestions for troubleshooting them. If a problem persists after
these actions have been taken, contact Parks Medical Electronics, Inc.
Problem
Situation
Suggested Actions
(continued)
3.0
Hard to hear
blood sounds (poor
signal: noise ratio)
(continued)
3.1
Too much noise
(continued)
3.1.5
Check for electromagnetic interference
Identify and eliminate the source:
If the noise is a buzz or hum, the ballast
1.
in
fl
uorescent lights, motors, and battery
chargers are suspect.
Try turning off lights and unplugging nearby
2.
devices. Circuitry in cell phones and laptop
computers can cause interference even
when turned off.
3.2
Weak signal
3.2.1
No sound or very little sound:
If battery indicator lamp is blinking, see 2.2
•
Check headphone/speaker connection:
•
Listen for sound with headphones. Then
1.
unplug the headphones and listen for sound
from the speaker. If there is sound in the
headphones, but not in the speaker with the
headphones unplugged, the inside of the
headphone jack is probably bent.
Unplug the headphones.
2.
Remove the four screws on the outside
3.
corners of the front panel and gently remove
the Doppler unit from the case.
Turn the volume control all the way up and
4.
squeeze the contacts on the inside of the
headphone jack.
If you hear bursts of sound from the speaker,
5.
bend the contacts to restore the connection.
3.2.2
The speaker is loud, but
fl
ow sounds are weak:
Check the frequency shown above the jack and
•
the probe frequency to be certain they are the
same. If not, obtain probe of matching frequency.
If you have another Parks Doppler unit of the
•
same frequency and a probe that works with it,
try the suspect probe on the good Doppler unit
and the good probe on the suspect Doppler unit.
If the
•
probe is suspect, replace the probe.
If the Doppler unit is suspect, call technical
•
support.
Probes fail more often than Doppler units. If you
•
do not have extra equipment to check against,
order a new probe.
If replacing the probe does not solve the
•
problem, contact technical support.
Summary of Contents for 915-BL
Page 2: ...2 Parks Medical Electronics Inc Aloha Oregon U S A ...
Page 24: ...24 Parks Medical Electronics Inc Aloha Oregon U S A ...
Page 26: ...26 Parks Medical Electronics Inc Aloha Oregon U S A Appendix ...
Page 27: ...27 915 BL Dual Frequency Doppler Appendix ...
Page 28: ...28 Parks Medical Electronics Inc Aloha Oregon U S A Appendix ...
