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User Manual
Rev. 1.0 - 29/11/05
PTRL NV/3 & RXRL NV/3
5.4.10 Checking incoming field and noise
The receiver input signal must have sufficient strength to ensure proper receiver
operation and good quality of the carried low-frequency signal. Quality being equal,
stereo transmission requires a much stronger signal than mono transmission. Typically,
signal needs to be 20dB higher.
Incoming field expressed in dBm may be viewed on receiver display. However, we
recommend taking an accurate reading using a spectrum analyser.
The recommend incoming signal for good stereo reception is -50 ÷ -60 dBm, the
equivalent of 200 ÷ 700 mV . On the other hand, an incoming signal in the -70 to -80
dBm range, i.e. 20 to 70 mV will be sufficient to provide good quality mono
transmission when the reception channel is free from noise.
In spite of the high-quality front end circuitry and the input filters, the incoming signal
needs to be reasonably clean in the reception channel. Perform a spectrum analysis
to ensure that channel is clean (incoming frequency ±300 kHz). In addition, any strong
signals falling within the input filter pass-band may cause the receiver to malfunction
or damage. In the event there are other radio link transmitters nearby, ensure that the
return signals from such transmitters to the antenna do not exceed -30dBm in the
preset reception band, which is typically about 50 MHz. Any stronger signals up to -
20 dBm require a verification to establish proper receiver operation under such
conditions.
Providing an adequate margin for the incoming signal is important to compensate
for possible fluctuation due to fading, multipath or added noise caused by adverse
weather or ambient conditions. It is a good rule to provide up to 20-30 dB as a worst-
case margin. In practice, however, this is hard to achieve.
5.4.11 "Muting" operation and setting and field relay
The receiver incorporates a muting circuit for the event the incoming field drops below
a predetermined level. When signal is weak or missing, a strong white noise will be
present at the receiver audio output, leading to severe inconvenience.
The muting threshold can be set from the setup menu; we recommend setting this
threshold well below the incoming signal level. Recommended settings are -90 dBm
for mono transmission and -80 dBm for stereo transmission (highly disturbed signal).
Muting operation may be enabled or disabled from the menu.
Regardless of whether muting is enabled or disabled, an internal field relay will
energise/deenergise upon reaching the set threshold; relay contacts have output
connections to enable remote control.
Summary of Contents for PTRL NV/3
Page 1: ...PTRL NV 3 RXRL NV 3 User Manual Volume 1 Manufactured by Italy...
Page 4: ...PTRL NV 3 RXRL NV 3 ii User Manual Rev 1 0 29 11 05 This page was intentionally left blank...
Page 8: ...4 52 User Manual Rev 1 0 29 11 05 PTRL NV 3 RXRL NV 3 This page was intentionally left blank...
Page 55: ...51 52 User Manual Rev 1 0 29 11 05 PTRL NV 3 RXRL NV 3 10 Ensemble View 10 1 PTRL NV 3...
Page 56: ...52 52 User Manual Rev 1 0 29 11 05 PTRL NV 3 RXRL NV 3 10 2 RXRL NV 3...