DB
ELETTRONICA TELECOMUNICAZIONI S.p.A.
PM 1000 – 1 kW FM Broadcasting Transmitter - U
SER
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ANUAL
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An internal deviation limiter controls the maximum frequency deviation, thus avoiding adjacent
channel interference in case of accidental over modulation. In order to limit over modulation, it is
necessary to insert the jumper jp6 in the modulation board to enable the limiter.
Valuable characteristics of PM1000 include intelligent protections. Circuits to protec from load
mismatching (VSWR) and overtemperature (TEMP) allow to otain a very high reliability in all
conditions. Every alarm condition is monitored by means of front panel leds.
The front panel led bar enable the full, easy and fast verification of the main parameters and
condition of operation. The output power, the reflected power, the voltage supply of the power
amplifier, the frequency deviation, L&R audio level, and MPX are continuously monitored.
It is possible, using the front panel adjustments, to control the following settings: output power
(PWR adj.), frequency deviation (DEV adj.), transmitting frequency (option /C), manual/remote
control selection (option /R) and the mono/stereo selection (option /S).
An output 10
th
order elliptic LP filter ensures a pure RF spectrum, compatible with the most
stringent international requirements. As well, a high efficiency switching mode power supply
reduces the power consumption, and ensures reliable operation.
Summary of Contents for PM 1000
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