Atten AT5010 Manual de instrucciones - Página 12

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Operating conditions

The instrument has been designed for indoor use.

The permissible ambient temperature range during

operation is + 10 (+50 F)

+40

(+104 F).

It may occasionally be subjected to temperatures

between +10

(+50 F) and -10

(+14 F)

without degrading its safety. The permissible am

bient temperature range for storage or transportation

is -40

(-40 F)

+70

(+158 F). The

maximum operating altitude is up to 2200m

(non-operating 1500m). The maximum relative

humidity is up to 80%.

If condensed water exists in the instrument it should

be acclimatized before switching on. In some cases

(e.g. extremely cold spectrum analyzer) two hours

should be allowed before the instrument is put into

operation. The instrument should be kept in a clean

and dry room and must not be operated in explosive,

dusty, or moist environments. The spectrum

analyzer can be operated in any position, but the

convection cooling must not be impaired. For

continuous operation the instrument should be used

in the horizontal position, preferably tilted upwards,

resting the tilt handle.

The specifications stating tolerances are only

valid if the instrument has warmed up for 60

minutes at ambient temperature between +

(+59 F) and +30

(+86 F). Values

without tolerances are typical for an average

instrument.

Warranty

ATTEN warrants to its Customers that the products

it manufactures and sells will be free from defects in

materials and workmanship for a period of 1 years.

This warranty shall not apply to any defect, failure

or damage caused by improper use or inadequate

maintenance and care. ATTEN shall not be obliged

to provide service under this warranty to repair

damage resulting from attempts by personnel other

than ATTEN representatives to install, repair,

service or modify these products.

In order to obtain service under this warranty,

Customers must contact and notify the distributor

who has sold the product.

Each instrument is subjected to a quality test with

10 hour burn-in before leaving the production.

Practically all early failures are detected by this

method. In the case of shipments by post, rail or

carrier it is recommended that the original packing

is carefully preserved. Transport damages and

damage due to gross negligence are not cover by the

warranty.

In the case of a complaint, a label should be

attached to the housing of the instrument which

describes briefly the faults observed. If at the same

time the name and telephone number (dialing code

and telephone or direct number or department

designation) is stated for possible queries, this helps

towards speeding up the processing of warranty

claims.

Maintenance

Various important properties of the Spectrum

Analyzer should be carefully checked at certain

intervals. Only in this it largely certain that all

signals are displayed with the accuracy on which the

technical data are based.

The exterior of the instrument should be cleaned

regularly with a dusting brush. Dirt which is

difficult to remove on the casing and handle, the

plastic and aluminum parts, can be removed with a

moistened cloth (99% water +1% mild detergent).

Spirit or washing benzine (petroleum ether) can be

used to remove greasy dirt. The screen may be

cleaned with water or washing benzene

[but not with spirit (alcohol) or solvents], it must

then be wiped with a dry clean lint-free cloth. Under

no circumstances may the cleaning fluid get into the

instrument. The use of other cleaning agents can

attack the plastic and paint surfaces.

Switching over the mains/line voltage

The spectrum analyzer operates on mains/line

voltages of 115V AC and 230V AC. The voltage

selection switch is located on the rear of the

instrument and displays the selected voltage can

be selected using a small screwdriver. Remove the

power cable from the power connector prior to

making any changes to the voltage setting. The

fuses must also be replaced with the appropriate

value (see table below) prior to connecting the

power cable. Both fuses are externally accessible by

removing the fuse cover located above the 3-pole

power connector.

The fuseholder can be released by pressing its

plastic retainers with the aid of a small screwdriver.

The retainers are located on the right and left side of

the holder and must be pressed towards the center.

The fuse(s) can then be replaced and pressed in until

locked on both sides.

Use of patched fuses or short-circuiting of the

fuseholder is not permissible; ATTEN assumes no

liability whatsoever for any damage caused as a

result, and all warranty claims become null and void.

Fuse type

Size 5 20mm,

250-Volt AC,

Must meet IEC

specification 127,

Sheet lll (or DIN 41 662

or DIN 41 571, sheet 3)

Time characteristic: time-lag

Line voltage: 115V~

10% Fuse rating: T315mA

Line voltage: 230V~

10% Fuse rating: T160mA

Introduction

The spectrum analyzer permits the detection of

spectrum components of electrical signals in the

frequency range of 0.15 to 1050MHz. The detected

signal and its content have to be repetitive. In

contrast to an oscilloscope operated in Yt mode,

where the amplitude is displayed on the time

domain, the spectrum analyzer displays amplitude

on the frequency domain (Yf). The individual

spectrum components of "a signal" become

visible on a spectrum analyzer. The oscilloscope

would display the same signal as one resulting

waveform.

The spectrum analyzer works according to the triple

superhet receiver principle. The signal to be

measured (fin = 0.15MHz to 1050MHz) is applied

to the 1st mixer it is mixed with the signal of a

variable voltage controlled oscillator (fL0 1350MHz

2350MHz).This oscillator is called the 1st LO (local

oscillator). The difference between the oscillator

and the input frequency (fL0 fin = 1st IF) is the first

intermediate frequency, which passes through a

waveband filter tuned to a center frequency of

1350MHz. It then enters an amplifier, and this is

followed by two additional mixing stages,

oscillators and amplifiers. The second IF is 29.

875MHz and the third is 2.75MHz. in the third IF

stage, the signal can be selectively transferred

through a filter with 400KHz or 20KHz bandwidth

before arriving at an AM demodulator. The

logarithmic output (video signal) is transferred

directly, or via a low pass filter to another amplifier.

This amplifier output is connected to the Y

deflection plates of the CRT.

The X deflection is performed with a ramp

generator voltage. This voltage can also be superim-

posed on a dc voltage which allows for the control

of 1st LO. The spectrum analyzer scans a frequency

range depending on the ramp height. This span is

determined by the scanwidth ser-ting In ZERO

SCAN mode only the direct voltage controls the 1st

LO.

The AT 5011 also includes a tracking generator. This

generator provides sine wave voltages within the

frequency range of 0.15 to 1050MHz. The tracking

generator is determined by the first oscillator

(1st LO) of the spectrum analyzer section. Spectrum