Telex C-2002 - Manual (Page 14)

8
Vega’s C-2002
Console # J8 Position Impedance Impedance Loss (dB)
1 A 604 604 0.0
2 B 10k 569 -0.5
3 B 10k 539 -1.0
4 B 10k 511 -1.5
5 B 10k 486 -1.9
6 B 10k 464 -2.3
Level adjustment can be made to the receive audio by entering the setup mode or adjusting the RX level POT inside
the C-2002.
4.2.6 TX Side Settings
The C-2002 TX output circuitry has a DPDT relay that is used to connect and disconnect the TX output transformer
from the TX line based on PTT status. This allows a very large number of consoles to be attached to the line in
parallel, because only the transmitting unit will be directly connected to the line. When not transmitting, the DPDT
relay is connected to 600 ohms or open circuit depending on the number of console connected in parallel to the line.
If only one console is attached, this unit should have J16 (Line 1) or J26 (Line 2) in the “A” position. This makes it
the effective master and terminates the line with 600 ohms. If there are more than one console connected in parallel,
one console should be designated as the master by placing J16 (Line 1) or J26 (Line 2) in the “A” position and the
remaining consoles should be designated as a slave and should have J16 (Line 1) or J26 (Line 2) placed in the “B”
position. In this manner, the impedance looking back into the parallel configuration of consoles is still 600 ohms.
Figure 7 shows the basic configuration. The C-2002 could also be the master in this configuration. NOTE: If any of
the consoles connected in parallel are not C-2002’s, then all the C-2002’s should be configured as slaves.
Additionally, J2 (Line 1) or J4 (Line 2) should be used as a TX line impedance correction if there are consoles other
than the C-2002 connected in parallel. J2 (Line 1) or J4 (Line 2) position “B” adds another 600ohms to the output
TX line. J2 (Line 1) or J4 (Line 2) Position “A” is straight through.
Master Slave Slave Slave
J12 POS A J12 POS B J12 POS B J12 POS B
C2000 Multiple Console Configuration
Leased
Line
600
ohms
open open open
Figure 7 Master/Slave Console Configuration.
4.2.7 Transmit Monitor
In a four-wire system with parallel consoles, the transmit line may be monitored. Refer to section 4.3.2, the monitor
level setup on adjusting the level. The transmit monitor is not needed in two-wire mode as the transmit audio is
already on the receive circuit. The transmit monitor, in 4 wire mode, is used to detect transmit activity for the TX
Detect LED.