OPERATION
67
d.
By default, audio is muted when Analyze Mode is entered. Press
Mute
or adjust the
volume using the
Vol^/v
keys to hear the demodulated audio through the OSCOR unit’s
speakers. You can also use headphones to listen to the demodulated audio. Plugging
headphones into the headphone output will automatically mute the built-in speakers.
e.
For improved clarity, adjust the Gain value.
The analyze screen for Audio Demodulation consists of two plots. The upper plot is the frequency
spectrum. The lower plot is an oscilloscope view of the demodulated signal. Notice that the cursor
in Analyze Mode is slightly different from Sweep Mode. The dotted vertical line represents the
frequency of the main carrier. This value is displayed at the top center of the screen. The solid lines
to either side of the dotted line represent the limits of the filter bandwidth selected in step 2c
above.
3.
For
VIDEO
demodulation schemes:
a.
From the Demod Sub-menu, select the
Video
icon to change the demodulation scheme.
b.
The OSCOR will automatically determine the video format of the signal that it is tuned
to. It has the capability of decoding most variants of NTSC, PAL, & SECAM systems.
c.
Select the type of demodulation that you want to use: AM or FM
d.
Select the filter bandwidth that you wish to use: 12.75 MHz, 6.375 MHz, 800 kHz, 200
kHz
e.
The volume of the demodulated audio can be adjusted using the
Vol ^/v
keys on the
OSCOR unit and can be muted with the
Mute
key.
f.
For improved clarity, adjust the Gain value. You may find it helpful to use the
oscilloscope display to assist with adjusting the gain. Adjust the gain until the
demodulated video signal is easily seen on the oscilloscope at a good level without any
clipping.
g.
For video signals with an inverted sync pulse, the OSCOR provides the option of
inverting the video signal. If you have adjusted the gain in the previous step using the
oscilloscope so that the video signal is at a good level, but the OSCOR is still not
demodulating any video, try toggling the
Invert
icon in the Demod Sub-Menu to get the
video signal to tune in.
Summary of Contents for OSCOR Blue
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