Telex MCE325 - Manual (Page 23)

2-3
2 When a two-wire line is connected to channel one and a four-wire line is connected to channel
B.
For all other intercom line configurations that use two-wire lines, DS3 must be set to the “on”
position for four-channel operation.
NOTE *J19 and J20 jumpers should be in “off” positions when two-wire lines are used.
Table 2.2 Jumper functions and default settings.
Jumper Number Jumper Function Default Setting
J4 Assigns PROGRAM A input to two-wire CH 3 or four-wire CH B.
Not assigned: pins 2 & 3 shorted.
Assigned: pins 1 & 2 shorted (IFB to CH 3). Not assigned
J5 Assigns PROGRAM B input to two-wire CH 4.
Not assigned: pins 2 & 3 shorted.
Assigned: pins 1 & 2 shorted (IFB to CH 4). Not assigned
J6 Selects two-wire CH1 and CH 2, or four-wire CH A output. (See J19
for CH A input.)
CH1 and CH 2 selected: pins 2 & 3 shorted.
Four-wire CH A output selected: pins 1 & 2 shorted. Two-wire operation
J7 Selects two-wire CH 3 and CH 4, or four-wire CH B output. (See J20
for Ch B input.)
CH 3 and CH 4 selected: pins 2 & 3 shorted.
Four-wire CH B output selected: pins 1 & 2 shorted. Two-wire operation
J16 Assigns mono mix of the PROGRAM A and B inputs to the left
headphone.
Not assigned: pins 2 & 3 shorted.
Assigned: pins 1 & 2 shorted. Assigned
J17 Assigns mono mix of the PROGRAM A and B inputs to the right
headphone.
Not assigned: pins 2 & 3 shorted.
Assigned: pins 1 & 2 shorted. Assigned
J18 Assigns mono mix of the PROGRAM A and B inputs to the speaker.
Not assigned: pins 2 & 3 shorted.
Assigned: pins 1 & 2 shorted. Assigned
J19 Selects four-wire CH A input. Off (not used): pins 2 & 3 shorted.*
On when LISTEN 1 button is on: pins 1 & 2 shorted.
Always on: pins 3 & 4 shorted. Off
J20 Selects four-wire CH B input. Off (not used): pins 2 & 3 shorted.*
On when LISTEN 2 button is on: pins 1 & 2 shorted.
Always on: pins 3 & 4 shorted. Off
J24 Selects unbalanced or balanced dynamic mic input.
Unbalanced: pins 2 & 3 shorted.
Balanced: pins 1 & 2 shorted. Unbalanced mic input