Clear-Com HB-704 - Manual (Page 16)

H B - 7 0 2 / H B - 7 0 4 T W O - A N D F O U R - C H A N N E L H E A D S E T S T A T I O N S 3 - 2
BLOCK DIAGRAM OF HB-704 FOUR-CHANNEL HEADSET STA-
TION
Figure 3-5 HB-704 Block Diagram
TROUBLESHOOTING TIPS
SYMPTOM CAUSE SOLUTION
System does not operate. Talk
button does not light amber
when talk button is pressed. (1) The HB-702 or HB-704 doesn’t
have an intercom connection. If the
EB-4W four-wire option module is
connected, the HB-702 may not be
receiving AC power. (1) Check connections and cable.
(2) The HB-702 or HB-704 has an
internal failure. (2) Unit requires servicing.
Headset does not operate. Talk
button lights amber when talk
button is pressed. (1) The headset is unplugged, the
intercom level knob is turned all the
way down, or the channel switch is
set to an unused channel. (1) Adjust controls appropriately.
(2) Defective headset. (2) Test with another headset.
EQ/
LIM
Headset
Mic
Sidetone
Null
Call
Light
Intercom
Volume
Call Send &
Receive
Headset
Output
Mic
Mute
Long Line
Talk
RMK
Microprocessor
Talk
Latch
Disable
Call TW Option
Channel
Switch
Ch. A
Power
Ch. B
Common
+30 VDC
Ground
Ch. C
Ch. D