ZETRON 4000 Series, Installation Manual

Page: 99 / 418

99
Series 4000 Phone Coupler (Optional)
Jumper Switch Settings
Table 37: Jumper switch settings
* Factory default setting.
Variable Resistors
Table 38: Variable resistors
Switch Description Settings
JP1 Receive gain A = LO *
B = HI
JP2 Not installed N/A
JP3 Source for Off Hook signal A = Internal
B = External *
JP4 Selects decode polarity for the external tone decoder A = Valid Low
B = Valid High *
JP5 Selects proper de-emphasis network for receive audio A = Speaker audio *
B = Discriminator audio
JP6 Sets polarity for Off Hook input A = High
B = Low *
JP7 Transmit gain setting A = HI *
B = LO
JP8 N/A N/A
Resistor Description
R1 * Sets the threshold for the internal carrier detector circuit.
R2 Sets the receive level from the console. The range over
which this control acts is set by JP1.
R3 Sets the transmit level to the console. The range over
which this control acts is set by JP7.
R43 * Sets the VOX circuit threshold.
R46 Sets the threshold on the external COR input.
R95 BAL R — used with BAL C to balance the hybrid
(match the coupler to the phone line).
R96 BAL C — used with BAL R to balance the hybrid
(match the coupler to the phone line).
R100 * Sets the sensitivity of the Dial Click decoder circuit.
* Not used in normal operation of the phone coupler.