R.V.R. Elettronica PTRL-NV/S3, Техническое руководство

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R.V.R. ELETTRONICA S.r.l. (BO) Pag. 50
PTRLNV/S3 - Technical and Maintenance Manual
7) Calibrate the VCO as detailed in paragraph "Calibration of the VCO"
of the RXRL-NV manual.
8) Calibrate the 6 compensators, situated on the two filters FIL1 and
FIL2 of the Front-end Mixer, for the maximum R.F. signal, checking
against the corresponding reading on the receiver's meter (maximum
R.F. signal displayable = -47 dBm).
6.6 TRANSMITTER AUDIO DEVIATION AND DISTORTION FIGURES
To make this measurement, configure the unit according to SETUP D
(Fig.12) and carry out the following procedures:
SETUP D / Fig.12
1) Adjust the signal generator for a signal level of -10 dBm (0dBm for
american versions) at the MONO and STEREO inputs.
2) Configure the modulation analyzer to rear deviation (P+).
3) Check that the deviation reading for the PTRL-NV/S3 is 75 KHz and
if not, adjust trimmer R8 (inside the VCO) to obtain it.
4) Configure the audio analyzer to read distortion (with 50 uS de-
emphasis for european versions and 75 uS for american versions).
5) Check that the distortion figure is better than 0.05% with low-pass
and high-pass filters of 20 KHz and 30 Hz respectively, for both
MONO and STEREO inputs.