User Manual
EASy-PLUS
®
User Manual
– 27
TRILITHIC
Rev 1.02
7.5 Single (Composite) I.F. Source Modulator Installation (IFS-3)
The I.F. modulator receives its video signal from the CG VIDEO OUT at the rear of the EASy-PLUS® and audio from the
terminal strip and modulates these signals onto I.F. subcarriers. Once the IFS-3 source modulator is mounted, connect
the RF OUT port to the I.F. IN port on the Primary LS-16P.
7.6 Precision I.F. Level Alignment of the LS-16P Lossless Splitter
The LS-16P was designed for precision I.F. output level adjustment. In most instances, different modulators or proces-
sors require different I.F. input levels to maintain proper RF output levels due to the absence of an AGC at the I.F. stage.
It is imperative that the headend maintain the same R.F. output level on each channel during an entire E.A.S. sequence
of events. When alternate I.F. levels match those I.F. levels which are currently present at the rear of the modulator or
processor, system wide stability of the trunk amps, pilot carriers, slopes, R.F. levels and scrambling systems will be
maintained.
DC power is delivered through the coaxial cable’s center conductor to enable the Secondary LS-16P(s), the SW-1(s),
and the SW-4(s) switches.
CAUTION: DO NOT INSTALL FIXED OR VARIABLE ATTENUATOR PADS IN THE INPUT OR OUTPUT CABLES OF
ANY LS-16P LOSSLESS SPLITTER. ELECTRICAL SHORTING OF THESE DEVICES MAY OCCUR.
The I.F. alignment procedure consists of setting the output level of the I.F. source modulator and then setting the output
levels on the Primary and Secondary LS-16P(s) for proper I.F. levels at the rear of the modulators and processors. The
Master Gain on all LS-16P(s) is factory set to unity gain. This adjustment should not need to be reset. Each 20dB
potentiometer on the front panel of the LS-16P is factory set to 0 dB loss (i.e.: 42 dBmV output on each port of the LS-
16P if the IFS-3 is set to 42 dBmV output.)
The test point on the front panel of the LS-16P(s) is to check for signal presence ONLY. No test alignment measure-
ments should be made at this test point.
7.7 Procedure for precision I.F. Alignment:
1. Set the output level of the I.F. source modulator to maximum and then pad its output down to 2 dBmV higher
than the highest I.F. level on your modulators/processors (typically 32-42 dBmV). Set the audio carrier level
13-17 dBmV down from the video carrier.
2. Turn all J1 - J16 dip switches on the front panel of the Primary LS-16P to OFF (disabled), except for those dip
switches which control the feeds of the Secondary LS-16P(s) INPUTS. These dip switches will remain ON
(enabled) at all times.
3. Enable the I.F. alignment mode in the menu system of the EASy-PLUS
®
encoder/decoder.
4. Using a spectrum analyzer or field strength meter connected to the trunk line test point, identify the channel
under alignment.
5. If applicable, be sure to disable any I.F. AGC switches on all modulators in the headend under I.F. alignment.
6. Looking at the channel under alignment on the spectrum analyzer or field strength meter, note the output level.
7. Turn the dip switch ON (enable) for the channel under setup, ONLY. This will enable the SW-1 or SW-4 switch
at the rear of the modulator or processor under setup. You should now see the “I.F. Alignment Screen” appear
on the television on the channel under test channel.
8. Using the respective potentiometer J1 - J16 on the front of the LS-16P for the channel under alignment, turn
the potentiometer counterclockwise until the exact R.F. output level is achieved on the spectrum analyzer or
field strength meter.
9. Turn the appropriate dip switch back OFF (disable) on the LS-16P.
10. Proceed to the next channel and repeat steps 4 through 10 until all channels are aligned.
11. Turn the I.F. AGC(s) ON for all modulators.
12. At the keypad of the EASy-PLUS unit, take the menu system out of I.F. alignment.
13. Turn all dip switches ON (enable).
CAUTION: The EAS system will not trigger in the automatic mode for an EAS alert while the system is in the “I.F.
Alignment” mode.
You have now completed the composite precision I.F. alignment procedure.