Test Modes - Orban OPTIMOD-FM 8500S Operating Manual

OPTIMOD-FM DIGITAL

Test Modes

Setup: Test
Parameter
Labels
MODE
BYPASS GAIN
TONE FREQ
TONE LVL
TONE CHAN
PILOT
The Test Modes screen allows you to switch between O
When you switch to B
restored when you switch back to O
Table 3-13 shows the facilities available. Facilities are self-explanatory, except for the
following:
•
The T
L
ONE VL
tone contributes 9% to the total modulation. Hence, a T
produces 100% modulation (91% + 9%).
Note that when the Optimod is in T
puts are set to F
deemphasis to the output of the tone oscillator. Applying deemphasis this way is
only correct if equipment downstream from the Optimod, like a transmitter's ste-
reo encoder, applies preemphasis before final transmission.
•
In B mode, preemphasis is still applied to the signal path. The B
YPASS
control calibration allows enough internal headroom to make swept frequency
response measurements without internal clipping. When the B
is set to 0.0 dB and the AI R
of approximately –17 dB from the analog input to the analog output at 100 Hz.
If the AO P
RE
emphasis, the gain from analog input to analog output will be approximately 0
dB at 15 kHz.
Units Default
--- Operate
dB 0.0
Hz 400
% 91
--- L+R
--- ON
Table 3-13: Test Modes
or T , the preset you have on air is saved and will be
YPASS ONE
PERATE
control is calibrated under the assumption that the stereo pilot
(instead of P
LAT
VU control is set to 0.0 dBu, you will observe a gain
EF
control is set to P
-
E RE
Range (CCW to CW)
Operate, Bypass, Tone
−18 ... +25
16, 20, 25, 31.5, 40, 50,
63, 80, 100,
200, 250, 315, 400, 500,
630, 800, 1000, 1250, 1600,
2000, 2500, 3150, 4000, 5000,
6300, 8000, 9500, 10000,
12500, 13586.76, 15000
0 ... 121
L+R, L−R, LEFT; RIGHT
ON, OFF
PERATE
.
mode and its analog or digital L/R out-
ONE
-E ), these outputs apply 50μs or 75μs
RE MPH
and the 8500S is configured for 75 µs pre-
-
E
OPERATION
Step
---
1
LOG
125, 160,
1
---
---
, and T
, B
YPASS ONE
L setting of 91%
ONE VL
G
YPASS AIN
control
G
YPASS AIN
3-77
.