R.V.R. Elettronica HC4, Руководство пользователя

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HC4
29 / 34 User Manual Rev. 1.0L - 01/04/02
and at minimum power.
3) On the coupler, set the display for the visualization of forward power.
4) Set the variable capacitor in their middle position.
5) Gradually increase the exciter power until the overall output power of the
transmitter reaches around the 80% of its nominal power.
6) Adjust the variable capacitors (1) and (2) (Figure 9.1) related to the first
amplifier, to maximize the forward power measured in the coupler
Figure 9.1
7) Adjust the variable capacitors (3) and (4) related to the second amplifier, still
maximizing the forward power measured by the coupler.
8) Adjust the variable capacitors (5) and (6) related to the third amplifier, still
maximizing the forward power measured by the coupler.
9) Adjust the variable capacitors (7) and (8) related to thefourth amplifier, still
maximizing the forward power measured by the coupler.
10) Repeat steps 6 and 8 until the transmitter’s power reaches a value that cannot
be further rised.
11) Increase the exciter power and verify that the system can reach the station’s
nominal power.
12) Switch off the transmitter.
13) Put in place again the coupler’s upper cover.
Notes:
• The described procedure is the one optimized to adjust the coupler to work on
a certain channel (frequency). When the coupler has to be adjusted on the
whole FM band, start executing the procedure at 98.0 MHz, and then repeat it
at 87.5 MHz and 108.0 MHz, until the best tradeoff is met.
•
If the adjustment is done because one of the amplifiers has been substituted, it
is normally sufficient to operate only on the capacitors related to the substituted
amplifier.
7 5 3 1
8 6 4 2