Optimod-AM 9400 V1.2 Operating Manual - Orban
Optimod-AM 9400 V1.2 Operating Manual - Orban
Optimod-AM 9400 V1.2 Operating Manual - Orban
- No tags were found...
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
2-32<br />
INSTALLATION ORBAN MODEL <strong>9400</strong><br />
Overview of Transmitter Equalization<br />
The Transmitter Equalizer has a low frequency section to equalize tilt and a high<br />
frequency section to equalize overshoot and ringing. If you are adjusting a<br />
CQU<strong>AM</strong> <strong>AM</strong> stereo plant, you must also adjust a second set of high frequency<br />
controls (for the L–R channel). These L–R controls do nothing in a mono facility.<br />
The Transmitter Equalizer does not affect the <strong>9400</strong>’s HD processed output.<br />
The Transmitter Equalizer setup parameters are stored independently in the four<br />
Transmission Presets (See page 1-17). If you are driving two transmitters, you will<br />
usually dedicate either one or two Transmission Presets to each transmitter. Using<br />
two transmission presets per transmitter allows you to equalize that transmitter<br />
and its antenna load independently for day and night operation. This may<br />
be desirable if the transmission parameters (power or antenna pattern) change<br />
between day and night.<br />
In addition to the Transmitter Equalizer controls, you must set the LOWPASS,<br />
HIGHPASS, and POS PEAK controls in each preset you use.<br />
If you are only driving one transmitter and the plant’s parameters do not change<br />
between day and night, then you only need to use and adjust the default TX1 /<br />
DAY Transmission Preset.<br />
Description of the TX EQ Controls<br />
LF FREQ: Determines the frequency at which the response of the Tilt<br />
Equalizer section of the Transmitter Equalizer is up approximately +3dB.<br />
This control is only available for the L+R (envelope modulation) channel.<br />
LF GAIN: Determines the maximum amount of low frequency correction<br />
provided by the Tilt Equalizer section of the Transmitter Equalizer. The<br />
control is only available for the L+R channel.<br />
HF DELAY: Determines the frequency at which the delay equalizer section<br />
of the Transmitter Equalizer begins to add phase shift to correct for<br />
non-constant delay in the transmitter and antenna system. This control is<br />
available for both the L–R and L+R channels.<br />
The L–R channel is only of interest if you are equalizing a CQU<strong>AM</strong> <strong>AM</strong><br />
stereo installation. In mono installations, the L–R Transmitter Equalizer<br />
controls have no effect.<br />
HF GAIN: Determines the frequency at which the High Frequency Shelving<br />
Equalizer section of the Transmitter Equalizer begins to roll off the<br />
high frequency response, compensating for overshoot in the transmitter<br />
and antenna system. This control is available for both the L–R and L+R<br />
channels.<br />
Procedure for LF Equalization<br />
You will set up one <strong>9400</strong> Transmission Preset at a time.<br />
A) Connect the vertical input of the oscilloscope to the transmitter’s sampling<br />
loop (or other convenient source of RF).<br />
B) Connect the sync (or external trigger) input of the oscilloscope to an available<br />
<strong>9400</strong> analog output.