IKUSI TAL-800 Serie Mode D'emploi page 23

4 — RF SETUP
4.1 - FORWARD SIGNAL SETUP (WITHOUT ALSC FUNCTION)
From the headend output send a measured signal from a sweep generator or a multicarrier generator;
its level must comply with the engineering calculations. If the set-up is carried out with the entire
system's TV carriers, make sure that the headend output signal level complies with these same
calculations.
1. Remove the F load from the test D port and connect a spectrum analyzer. The measured levels are
19 ±1 dB lower than the real value.
2. EQUALIZATION. The broadband signal must show initially a positive slope (the higher the
frequency, the higher the level). Then turn the ECE variable equalizer clockwise in order to get a flat
response.
If despite turning ECE fully colckwise the flat response is not achieved, change the PSC plug-in link position to "3
dB", or if necessary to "6 dB", so that the slope changes its direction (the higher the frequency, the lower the
level); then set the flat response by turning ECE counterclockwise.
3. ATTENUATION. Read the level of the highest frequency carrier; this level must be under the
design value. Then turn the ATI variable interstage attenuator clockwise to set the design value.
If despite turning ATI fully clockwise the design value is not achieved, change the PAF and/or the PAA positions
(the change in the last only is possible if additional amplification has not been implemented) so that the read
level comes less than 6 dB above the desired value; then set the design value by turning ATI counterclockwise.
4. SLOPED RESPONSE. To feature a 6 or 12 dB sloped response place the PPB plug-in link in the
appropriate position ("6 dB" or "12 dB").
5. Disconnect the spectrum analyzer from the test D port and replace the F load.
INPUT TEST PORT
The amplifier has an internal RW output test port which can become transformed in a FW input test port; to do it,
place the PE1 and PE2 plug-in links in the positions indicated
30 ±1 dB lower than the real value.
After measuring return the PE1 and PE2 plug-in links to the established input configuration positions.
4.2 - FORWARD SIGNAL SETUP (WITH ALSC FUNCTION)
Important:
- If a 6 or 12 dB sloped response is desired, prior to begin the setup process place the PPB plug-in link
in the "6 dB" or "12 dB" position.
- Have ready the TMC-102 or TMC-142 ALSC circuit card to be installed later.
From the headend output send a measured signal from a sweep generator or a multicarrier generator;
its level must comply with the engineering calculations. If the set-up is carried out with the entire
system's TV carriers, make sure that the headend output signal level complies with these same
calculations.
1. Locate the 4 plug-in links of the ALSC/RW/INGRESS group and check that the first and fourth are
in the positions indicated as 0 and 9 (see Fig. 7).
2. Remove the F load from the test D port and connect a spectrum analyzer. The measured levels are
19 ±1 dB lower than the real value.
3. Place the PAF plug-in link in the "0 dB" position and, if no additional amplification has been
implemented, the PAA also in "0 dB".
(Unfold pages 32/33)
on the internal label E1. The measured levels are
T
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