5.2 Adjust Pilot Level; Pilot Phase Adjustment; Channel Separation - Solidyne Orión 462 MKII Manual De Operación

5.2 Adjust Pilot Level

a) Connect to ground the test point TP1 (R246)
in order to eliminate the 19 KHz pilot tone.
Use a good DC-20
oscilloscope at the MPX output connector.
Using the display control, select the
output to 4 V peak to peak. Connect a sine
wave generator at the LEFT input of the audio
processor, at 1 Khz, + 4 dBm output. Verify
that the output waveform looks like FIG-1.
b) Replace the audio generator at the processors
Left input for audio program (music or voice).
Please carefully take note of this peak to peak
value; let name it Xpp.
c) Disconnect the audio program from the LEFT
input and disconnect the ground of the test
point TP1. Then, the 19 Khz pilot tone will
appear.
d) With the oscilloscope measure the peak to
peak value of the 19 Khz pilot tone; let name it
Ppp.
The percentage level of pilot tone will be:
Pilot Level [%] = 100.Ppp/Xpp
FIG.2 Pilot Phase 10X
26
Mhz calibrated
MPX
SOLIDYNE
e) Using the P4 control, adjust Ppp to the
desired value (normally 9 to 11 % is a good
value)
NOTE: If you have a Solidyne VA16 modulation
monitor or BELAR FMS-2 measurement set, you will be
able to measure pilot tone level from on-air transmission
and you can correct it using P4.
5.3

Pilot Phase adjustment

This method is an absolute system not dependent
from the calibration of the Modulation Monitor. You
will need a very good DC-20 Mhz oscilloscope
(Tektronix preferred) with vertical 10x undistorted
span. Proceed:
a) Change the SC-100 PHASE jumper (JF1)
from the Normal "N" position to calibrate "C"
position.
b) Input a sine wave generator at 1 KHz, +4 dBm,
at Left Channel of the audio processor. Adjust
the level of wave generator to get 4 Vpp MPX
output.
c) Connect the oscilloscope to the MPX output in
mode DC.
Use the sine wave output of audio generator,
to synchronize the oscilloscope sweep. Adjust
the sweep to 5 uS/Div. Modify with trigger
level, the center of the wave in order to have it
centered at screen.
Adjust vertical sensitivity to 50 mV/Div. You
must get a signal like FIG-2.
If not, you must do a slight change in the
frequency knob of the audio generator in order
to avoid integral multiplication factors that do
not allow you to appreciate the correct image.
Calibrate the P3 Phase Control to get zero
phase error. The phase error is indicated by
the tilt of the imaginary line between H1-H2
points. When this line is full horizontal, the
phase is correct.
e) Change the phase calibration jumper to
NORMAL mode ( "N" position).
5.4

Channel Separation

Due to the high channel separation of the Solidyne
SC-100, the only way to recalibrate to original
specifications, is to use as reference a good
ORION 462 MKII