Guardian Telecom Inc.
Installation & Operation
TBA Models
Page 20
9.2. Powering ON the TBA
Turn the AC power switch on the back panel to “ON”.
Verify that the “Go-Ahead” tone is heard briefly on all of the speakers attached.
9.3. Monitored Station Microphone Volume Adjustment
Monitored Station Volume (Microphone – R184) adjustment is done while listening to the output of
the audio on the speaker for another station. With a sound source that is expected to be near the
maximum level adjust R184 so that the sound is just starting to be distorted.
Alternatively adjust R184 so the signal on J15 pin 1 is at 0.1 volts RMS with a normal voice level.
Alternatively adjust R184 so that it is at 25% of the rotation clockwise.
9.4. Central Station Microphone Volume Adjustment
Press the Central Station PTT switch. Adjust the Central Station Volume (Microphone – R183).
Adjustment is done while listening to the output of the audio on the speaker for another station.
With a sound source that is expected to be near the maximum level adjust R183 so that the sound
is just starting to be distorted.
Alternatively adjust R183 so the signal on J15 pin 1 is at 0.1 volts RMS with a normal voice.
Alternatively adjust R183 so that it is at 50% of the rotation clockwise.
9.5. Ringer Volume Adjustment
Press the Monitored Station PTT switch. Adjust the Ring Volume (R186) to have a ringing signal
that is loud enough but does not distort.
Alternatively adjust R186 so the signal on J15 pin 1 is at 0.2 volts RMS.
Alternatively adjust R186 so that it is at 50% of the rotation clockwise.
9.6. Central Station Speaker Volume
Adjust Central Station Volume (R11) so that the voice from the Monitored Station is at a
comfortable level for the Central Station operator.
9.7. Station #1 Speaker Volume
Adjust Station #1 Volume (R47) so that the voice from the Monitored Station is at a comfortable
level for the Station #1 operator.
9.8. Station #2 Speaker Volume
Adjust Station #2 (R79) so that the voice from the Monitored Station is at a comfortable level for the
Central Station operator.
9.9. Station #3 Speaker Volume
Adjust Station #3 Volume (R110) so that the voice from the Monitored Station is at a comfortable
level for the Station #3 operator.
9.10. Optional Hum Cancellation
The jumper on JP2 should be removed and replaced. If the sound level of the background noise or
hum changes with this action, replace JP2 jumper to the location nearest R180. If the sound does
not change replace JP2 jumper to the location away from R180 and do not adjust R179.
Adjust R179 for the minimum noise from a station speaker. This is a subjective adjustment.
