R.V.R. Electronica PTRL, Руководство пользователя

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PTRL & RXRL LCD
43 / 44 User Manual Rev. 1.2 - 31/01/05
3
b
) Switch on the receiver and wait until that the lock has not happened on the working
frequency (LOCK led lit on). In order to control or to modify that the working
frequency is same to that one of the transmitter go to the Set menù (see cap.6.4.2)
4
b
) Check the presence of holes on the top cover and operate, on the basis of
conditions, as previously described in the point 4
a
).
5
b
) Check and obtain the maximum sensibility adjusting through the compensators
situate on the Front End card ; carry the RF value to full-scale express as bar in
the predefined menu (see chap. 6.4) or connect the oscilloscope to IF 10,7MHz
output (Chap. 7.5 [ 12 ]) and check to obtain the maximum level possible.
6
b
) Diminish gradually the signal level injected, continuing to adjust for the maximum
value the level of the IF 10,7MHz. Repeat this operation until that the signal injected
from the generator does not achieve the level of -47dBm (1mV), or minor in order
to optimize the calibration. In any case the full-scale must be at the level of -47dBm.
In both cases is advisable, in order to facilitate the operation, carry out the movement
to subsequent step, that is in the case that the difference between the new frequency
and that old one is
≥
¾ MHz to carry out one first perfunctory calibration on one
intermediate frequency between the old one and the new. in the following comes
described an example:
Old fq = 942 MHz
New fq = 957 MHz
Intermediate step at 948 MHz and 950 MHz, and then complete alignment to the
frequency of 950MHz.
This in order to avoid to exit completely from the resonance curves of the tuning
circuits complicating, therefore, the research of the tuning on the new frequency.
This example can be used subdividing the procedure in step of frequency more bring
closer, for example:
Old fq = 942 MHz
Step 1 = 945 MHz
Step 2 = 948 MHz
Step 3 = 953 MHz
Step 4 = 957 MHz (New fq)