PTX30-UHT Technical and Maintenance Manual
R.V.R. Elettronica S.r.l. (Bo) Pag. 10
CHAPTER 1
GENERAL DESCRIPTION
1.1 EXTERNAL DESCRIPTION
The PTX30-UHT is contained in a 19" 2U rack internally assembled
with modules mounted on a main chassis, all interconnected with
connectors, allowing an easy servicing and substitution.
On the front panel there are the regulations for the output power, the
audio input level and the meters of the main parameters.
On the rear panel, there are the mains inlet and the RF output connector.
1.2 ELECTRICAL DESCRIPTION
PTX30-UHT is a frequency agile exciter ranging from 87.5 to 108 MHz
in 10 KHz steps with a continuously adjustable output power from 3 to
30 Watt on a 50 Ohm load.
The low intermodulation and distortion values (typ.0.03%) and the high
signal to noise ratio (typ.80 dB) are the main performances of this
exciter.
A mains voltage selector, permits the use with various mains voltages.
1.3 METERS AND INDICATORS
The most important parameters of the exciter are checked with the
analog meter (15 Fig.1A, 11 Fig.1B) and the bar graph display (19 Fig.1A,
15 Fig.1B) present on the front panel.
The analog measures are selectable with the appropriate switch (10
Fig.1A, 6 Fig.1B) and are identified by the led indicator (11 Fig.1A,
7 Fig.1B).
The bar graph display (19 Fig.1A 15 Fig.1B), reads the peak deviation
in 5 KHz steps
The 5 digits central display (20 Fig.1A, 16 Fig.1B) reads the working
frequency which is selectable from the switches UP (9 Fig.1A, 5 Fig.1B)
and DOWN (7 Fig.1A, 3 Fig.1B), and memorized with ENTER (8 Fig.1A, 4
Fig.1B).
Three alarm condition leds provide indication of VCO unlocked (14 Fig.1A,
10 Fig.1B), excess output SWR (12 Fig.1A, 8 Fig.1B) and intervention by
a remote control (13 Fig.1A, 9 Fig.1B).
1.4 AUTOMATIC FREQUENCY CONTROL
The output frequency stability is guaranteed by a PLL (phase locked
loop) circuit with a temperature compensated crystal oscillator.
PTX30-UHT reaches the frequency lock condition in a maximum time of 30
seconds from the power on.
