— 55 —
CONNECTING THE 730 ENCODER
Check That
Jumper!
It is essential that the 730 Encoder is properly configured
for
the desired connection mode: sidechain or loop-through. Con-
sult Figure 2 to confirm that the encoder circuit board is prop-
erly jumpered before connecting the 730 Encoder to other air-
chain equipment.
Sidechain
Connection
(Preferred)
Using a BNC ‘T’ adapter at the composite/MPX output of the
stereo generator, connect one side of the ‘T’ directly to a wide-
band (composite/MPX) input of the FM exciter and the other
side to the
PILOT OR MPX INPUT
of the 730 Encoder as shown
in Figure 3. This is a bridging (high impedance) ‘sync’ connec-
tion when the circuit board is jumpered for sidechain operation
and has no effect on the composite/MPX signal.
Cable the
RDS OR MPX OUTPUT
of the encoder to a second wi-
deband (subcarrier) input of the FM exciter.
Figure 3 –
‘Sidechain’ Encoder Connection
Using a
Dedicated 19kHz
Sync Source
A stereo generator’s 19kHz RDS SYNC output
may
be con-
nected to the encoder
PILOT OR MPX INPUT
for sidechain oper-
ation. We do not recommend this, however, as this output may
not have an accurate phase relationship with the stereo pilot in
the composite/MPX output signal.
Loop-Through
Connection
In the loop-through mode, the output of the stereo generator is
cabled directly to the
PILOT OR MPX INPUT
of the 730 Encoder
as shown in Figure 4 on the following page. Connect the
RDS
OR MPX OUTPUT
of the encoder to a composite/MPX wideband
input of the FM exciter. When internally jumpered for loop-
through operation, the composite/MPX signal
passes through
the encoder with unity gain and the RDS subcarrier is added.
In the event of encoder power loss, the composite/MPX signal
MODEL 730 ENCODER
TCP/IP PILOT OR RDS OR MPX RS-232 LOCAL
LAN PORT MPX INPUT OUTPUT COM PORT TA CONTROL
FM EXCITER
1 2 3
–– SCA INPUTS ––
RF OUTPUT
MPX
INPUT
FM STEREO GENERATOR
PROGRAM
LINE IN
MPX OUT
