Operating instructions

LOCAL OPERATION
3-6
(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 interconnects 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 O symbol shows the RF output
connector and the P 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 [Ø], and LEVEL: [×] and [Ø].
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 [Ø] 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 [Ø] 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 [Ø] 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 [Ø] keys for span range and center frequency
adjustment. The LEVEL [×] and [Ø] keys are used for reference level adjustment. See
page 3-69.
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 center frequency and will not adjust below
zero or above the top frequency limit.
The LEVEL [×] and [Ø] 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
undefined signal, or assessing the squelch operating level of a receiver. It has no mechanical
stops. This control is also used to select items or digits from displayed lists, in conjunction with
TONES and SYSTEM modes. It is also used for certain finite adjustments to Avionics settings.
(10) Audio connections.
AF GEN OUT socket. The signal available at this BNC socket is the combined output from both
or either of the AF generators and/or the tones generator.
AF INPUT socket. Signals fed into this BNC socket can be measured using the AF counter, the
AF voltmeter and the distortion measuring circuits. It is also the input for the digital oscilloscope.
ACCESSORY socket. Used for connecting Directional Power Heads and other accessories. The
presence of these is automatically detected. The socket is also used for direct connection of a
headset, allowing modulation of the signal generator by a microphone and audio signal monitoring
through headphones.
When using the accessory microphone with PTT switch, automatic switching between Tx and Rx
modes using the PTT switch is possible.
WARNING