Operating Manual for COMMUNICATIONS SERVICE MONITOR

LOCAL OPERATION
WARNING
Terminator keys used to conclude a parameter value are on the right of the group. They are
coloured orange.
When setting a modulation level, the entry is completed using the Hz, kHz, MHz or % key. The
appropriate modulation type, FM or AM, is automatically selected.
(4), (5) & (6) RF input and output connectors.
The three sockets at the right hand edge of the front panel are the RF input/output connectors.
Refer to the Performance data section in Chapter 1 for measurement accuracy, maximum power
input levels and reverse power limits. The nominal impedance of all RF input and output circuits
is 50 W.
(4) ANTENNA connection. This is a female BNC connector, for ’Off Air’ measurements and
monitoring, using a suitable antenna. This connector can also be used for direct input of low
level signals.
(5) BNC RF output connector. This provides output from the RF signal generator.
(6) N type RF connector. This is dual function, input and/or output. A 20 dB Delta attenuator is
incorporated within the Service Monitor. This inter-connects the ’N type’ connector with the RF
generator output and the measuring receiver input, through the input/output selector switching.
Hot surfaces
Take care when touching the RF Input N Type connector after the application of high levels of
continuous power. If 50 W is exceeded for a prolonged period, the temperature of the connector
can become excessive.
(7) RF input select key. The [SELECT] key switches through all the RF connector combinations
available. The current selection is indicated by LEDs. The � symbol shows the RF output
connector and the � symbol shows the RF input connector.
(8) Increment adjustment keys. Under the variable control are the two pairs of increment
adjustment keys, FREQ (frequency): [�] and [�], and LEVEL: [�] and [�].
These enable the frequency and level of the RF generator or a selected AF generator to be
adjusted in pre-defined steps. The assignment and the value of the steps is shown on the display.
The FREQ [�] and [�] keys can be assigned to the Tx frequency value or either of the audio
generators when in the Tx TEST mode, the RF generator or either of the modulation generators
when in the Rx TEST mode, or either of the AF generators when the AF TEST mode is active.
The LEVEL [�] and [�] keys have the same options. The frequency keys and the level keys do
not have to be assigned to the same generator.
The FREQ [�] and [�] keys can be assigned to the RF generator frequency or transmitter
frequency as channel increments.
When operating in Dx TEST mode the increment keys are disabled.
The SPEC ANA mode uses the FREQ [�] and [�] keys for span range and centre frequency
adjustment. The LEVEL [�] and [�] keys are used for reference level adjustment. See
page 3-64.
The span is ranged up or down in a 1, 2, 5 sequence, from 1.0 kHz to 1.0 GHz.
Adjustment to the span by these keys is linear about the centre frequency and will not adjust
below zero or above the top frequency limit.
The LEVEL [�] and [�] keys adjust the reference level range of the spectrum analyzer in either
2 dB or 10 dB steps depending on the setting of the reference level vertical range.
(9) Variable control. The large rotary control under the data input keys is used to make adjustments
to frequencies and levels that require a finite change such as when matching a test signal to an
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