5
947137
TABLE 1
TROUBLESHOOTING CHART
PROBLEM
CORRECTIVE ACTION
No side tone
Check “A” Battery connections, polarity, and voltage.
No dial tone
Check option switch 1. Check “B” battery connections, polarity and voltage.
No lamps
Check lamp supply voltage and input. Verify that grounds are common at
power supply.
No audible signal at station dialed
Check signal voltage at supply and frame locations. Verify that bells and
buzzers are common at power supply.
Double signaling
Check option switch 2.
Continuous signaling -
stations 10-29
stations 30-39,
0, 5-9
Check option switch 3.
Check option switch 4.
Alert tone but no voice page at
station
Check option switches 3 and 4.
No volume to speaker
Check phone to speaker volume control.
Check * for audio present at tip, ring input BL/W, W/BL pair.
Check * for audio at signaled speaker pair at 66B block.
Check * for audio at input of speaker.
No volume to phone
Check speaker to phone volume control.
Check wiring to talkback speaker.
Remove all connections to inhibit pin and verify problem.
Hum heard at phone
Check wiring to speaker.
Possible magnetic interference from power supply - relocate unit 12” - 18”
away.
Check for noisy “A” battery.
No speaker cancel
Verify ground present at phone side of at least (2) 10K ohm resistors.
R.F. Interference
NOTE: The following solutions are listed in order of priority. Not all steps
may be necessary to eliminate or reduce R.F. Interference.
Use 12 AWG wire from equipment ground to water pipe ground.
Install a .05 MFD Ceramic disc CAPACITOR on the following terminals.
a. Talk battery to talk ground
b. Signal battery to signal ground
c. Tip to ring
d. Across each speaker pair
e. From inhibit lead (if used) to ground
NOTE: Do not apply ground directly to inhibit input.
* Use telephone test set
