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analyzer and tracking generator are frequency

synchronized.

Operating Instructions

It is very important to read the paragraph "Safety"

including the instructions prior to operating the

AT5010/11.No special knowledge is necessary for

the operation of the AT5010/11.The straightforward

front panel layout and the limitation to basic

functions guarantee efficient operation immediately.

To ensure optimum operation of the instructions

need to be followed.

Attention!

The most sensitive component of the AT 5010/

AT 5011 is the input section of the Spectrum

Analyzer. It consists of the signal attenuator

and the first mixer. Without input attenuation,

the voltage at the input must not exceed +10

dB (0.7 Vrms) AC or

25 volt DC. With a

maximum input attenuation of 40dB the AC

voltage must not exceed +20dBm.

These limits must not be exceeded.

otherwise the input attenuator and/or the fist

mixer would be destroyed.

When measuring via a LISN (line impedance

stabilization network) the input of the

Spectrum Analyzer must be protected by

means of a transient limiter (Az560)

Prior to examining unidentified signals, the presence

of unacceptable high voltages has to be checked. It is

also recommended to start measurements with the

highest possible attenuation and a maximum

frequency range (1000MHz). The user should also

consider the possibility of excessively high signal

amplitudes outside the covered frequency range,

although not displayed (e.g. 1200MHz). The

frequency range of 0Hz 150KHz is not specified for

the AT 5010/11 Spectrum Analyzer. Spectral lines

within this range would be displayed with incorrect

amplitude. A particularly high intensity setting shall

be avoided. The way signals are displayed on the

spectrum analyzer typically allows for any signal to

be recognized easily, even with low intensity.

Due to the frequency conversion principle, a

spectral line is visible at 0Hz. It is called

If-feedthrough. The line appears when the 1st

LO frequency passes the If amplifiers and

filters. The level of this spectral line is

different in each instrument. A deviation

from the full screen does not indicate a

malfunctioning instrument.

Control Elements

The front view picture of the instrument (see last

page) contains numbers referred to below.

(1) Focus

Beam sharpness adjustment.

(2) Intens

Beam intensity adjustment.

(3) Power

(Power ON and OFF)

If power is switched to ON position, a beam will be

visible on the screen after approximately 10 sec..

(4) TR

(Trace Rotation)

In spite of Mumetal-shielding of the CRT, effects

of the earth's magnetic field on horizontal trace

position cannot be completely avoided. A

potentiometer accessible through an opening can be

used for correction. Slight pincushion distortion is

unavoidable and cannot be corrected.

(5) Marker

ON/OFF

When the MARKER pushbutton is set to the OFF

position, the CF indicator is field on the horizontal.

When the switch is in the ON position, MK is lit

and the display shows the center frequency. The

marker is shown on the screen as a sharp peak. The

marker frequency is adjustable by means of the

MARKER knob and can be aligned with a spectral

line.

Switch off the marker before taking correct

amplitude readings.

(6) CF/MK

(Center Frequency/Marker)

The CF LED is lit when the digital display shows

the center frequency. The center frequency is the

frequency which is displayed in the horizontal

center of the CRT. The MK LED is lit when the

Marker pushbutton is in the ON position.The digital

display shows the marker frequency in that case.

(7) Digital Display

(Display of Center

Frequency / Marker Frequency)

7-segm. Display with 100KHz resolution.

(8) Uncal

Blinking to this LED indicates incorrectly displayed

amplitude values. This is due to scanwidth and filter

setting combinations which give to low amplitude

readings because the If-filters have not being settled.

This may occur when the scanned frequency range

(SCANWIDTH) is too large compared to the IF

bandwidth (20KHz), and/or the video filter

bandwidth (4KHz). Measurements in this case can

either be taken without a video filter or the

scanwidth has to be decreased.

(9) Center frequency

-Coarse/Fine

Both rotary knobs are used for center frequency

setting. The center frequency is displayed at the

horizontal center of the screen.

(10) Bandwidth

Selects between 400KHz and 20KHz IF bandwidth.

If a bandwidth of 20KHz is selected, the noise level

decreases and the selectivity is improved. Spectral

lines which are relatively close together can be

distinguished. As the small signal transient response

requires a longer time this causes incorrect

amplitude values if the scanwidth is set at too wide

a frequency span. The UNCAL. LED will indicate

this condition.

(11) Video Filter

The video filter may be used to reduce noise on the

screen. It enables small level spectral lines to

become visible which normally would be within or

just above the medium noise level. The filter

bandwidth is 4KHz.

(12) Y-Position

Control for adjusting the vertical beam position.

(13) Input

The BNC 50 input of the Spectrum Analyzer.

Without input attenuation the maximum permissi-

ble input voltages of

25V DC and +10dBm AC

must not be exceeded. With the maximum input

attenuation of 40dB the maximum input voltage is

+20dBm.

The maximum dynamic range of the instrument is

70dB. Higher input voltages exceeding the reference

level cause signal compression and intermodulation.

Those effects will lead to errone-ous displays. If the

input level exceeds the reference level, the input

level attenuation must be increased.

(14) Attenuator

The Input Attenuator consists of four 10dB

attenuators, reducing the signal height before

nter-ing the 1st mixer. Each attenuator is active if

the push button is depressed. The correlation of

selected attenuation, reference level, and baseline

level (noise level) is according to the following

listing:

Attenuation

Reference level

Base line

The reference level is represented by the upper

horizontal graticule line. The lowest horizontal

graticule line indicates the baseline. The vertical

graticule is subdivided in 10dB steps. As previously

pointed out, the maximum permissible input

voltages may not be exceede3d. This is extremely

important because it is possible that the Spectrum

Analyzer will only show a partial spectrum of

currently applied signals. Consequently, input

signals might be applied with excessive levels

outside the displayed frequency range leading to the

destruction of the input attenuator and/or the 1st

mixing stage. Also refer to INPUT.

The highest attenuation (4 10dB) and the highest

usable frequency range (scanwidth setting 50MHz/

DIV.) should be selected prior to any spectral to the

AT5010/11 input. This permits the detection of any

spectral lines which are within the maximum

measurable and displayable frequency range if the

center frequency is set to 500MHz. If the baseline

tends to move upwards upwards when the

attenuation is decreased, it may indicate spectral

lines outside the maximum displayable frequency

range (i.e.1200MHz) with excessive amplitude.

(15) Scanwidth

(Push buttons)

The SCANWIDTH selectors allow to control the

scanwidth per division of the horizontal axis. The

frequency/Div. can be increased by means of the

button, and decreased by means of the

button.

Switching is accomplished in 1-2-5 steps from

100KHz/div.to 100KHz/div. The width of the scan

range is displayed in MHz/div. and refers to each

horizontal division on the graticule. The center