System Description Party Line Telephone System PLTS
BCPT1010.SD.E2.doc, Version 1.0
BlueCom AG, 1.3.1999
11
4 J3KA Programming
The following functions are programmable and should be checked before the amplifier is
utilized:
Supply voltage range: -24 or -48 V (nominal)
Gain range: Low, Medium or High
4.1 Supply Voltage Range
Two supply voltages can be used with the bridging amplifier: -24 V or -48 V. A jumper is
provided on the main PC board (Na).
Note: When the bridging amplifier is operated from a -24 V supply the maximum output level
is reduced to +10 dBm.
4.2 Gain Range
In addition to the adjustment by the potentiometers (described in 3.4), three coarse gain
ranges are provided for each output. The range selection can be made by means of jumpers
located on the Nb board as follows:
Desired gain
Range selection
Port 1
Port 2
Port 3
Port 4
6 dB
Low
J1 L
J2 L
J3 L
J4 L
+6...+18 dB
Medium
J1 M
J2 M
J3 M
J4 M
+18...+30 dB
High
J1 H
J2 H
J3 H
J4 H
The jumpers are located on the Nb board and can be changed without dismantling the unit.
They are arranged in a row as follows:
Port 1
Bottom jumper J1
Port 2
Third jumper from top J2
Port 3
Second jumper from top J3
Port 4
Top jumper J4
4.3 Factory Programming
If not specified otherwise the J3KA's will be factory adjusted as follows:
Supply voltage -48 V
Gain range: "Low"
Gain: 0 dB
