ADVANTEST U3741, U3751 Service Manual

Spectrum Analyzers

Compact Design with High Performance
Pioneering 3 GHz/8 GHz Spectrum Analyzers are Now Available!

U3741/3751

The U3741/3751 portable spectrum analyzer

supports a great range of applications, from

use on production lines to system installation

and maintenance. Its digital IF enables dramatic

improvements in power measurement accuracy

for digitally modulated signals. Moreover, the

U3741/3751 provides twice the throughput of its

predecessor. A light and compact 3 GHz/8 GHz

spectrum analyzer, the U3741/3751 provides ba-

sic performance reliably and at a low cost.

●

Better measuring speed due to high-speed processing
(twice as fast as its predecessor)

●

Dramatically improved power measurement accuracy
for digitally modulated signals

●

Built-in 3 GHz/8 GHz pre-amp standard

●

Average display noise level:

-155 dBm/Hz@1 GHz, pre-amp ON

●

Tracking generator covering a frequency range of
100 kHz to 3 GHz

●

Option available for measurement of phase noise
characteristics

●

Lightweight and compact design, with a maximum
weight of only 5.6 kg

●

Continuous operation of up to 2.5 hours with the
battery pack

U3741/ 3751 Web Demonstration

Please access to the http://www.advantest.co.jp/en-index.shtml and click on the following links.

PRODUCTS & SUPPORT Electronic Measuring Instruments Products U3751

2

U3741/3751-1E Mar. ’07

75 Ω Input Impedance

Option Guide

● —

OPT.15

Used for measurement of CATV and TV signals

Product name

Main unit support

U3741

(9 kHz to 3 GHz)

U3751

(9 kHz to 8 GHz)

Model number Overview

High-Stability Frequency
Reference Source

●●

OPT.20

High-stability reference oscillator with an aging
rate of ± 2 x 10

-8

/day, ±1 x 10-7/year

EMC Filter

●

1)

●

1)

OPT.28

CISPR bandwidths are available for EMI
measurement.
RBW (6 dB down): 200 Hz, 9 kHz, 120 kHz, 1 MHz

High-Purity
Spectrum Analysis

●

1)

●

1)

OPT.70

High-purity spectrum analysis with -100 dBc/Hz
@ 10 kHz offset
RBW 30 Hz has also been added.

75 Ω Tracking Generator

●

2)

—

OPT.75

Used for evaluation of frequency characteristics
in a range from 100 kHz to 2.2 GHz.
Output power range: 107 to 47 dBµV

50 Ω Tracking Generator

●

1)

●

1)

OPT.76

Used for evaluation of frequency characteristics
in a range from 100 kHz to 3 GHz.
Output power range: 0 to -60 dBm

1) OPT.15 and OPT.75 cannot be installed simultaneously. 2) OPT.15 is required, and cannot be installed simultaneously with OPT.76.

IF OUT

21.4-MHz IF
signal output

VIDEO

Output to an
external VGA
monitor

Main function keys

Data Entry

GPIB

EXT TRIG USB

POWER CAL OUT

Soft-key block

RF INPUT

Control keys

EXT REF

Standard signal input
for external reference

LAN

Control and remote operation,
utilizing an external PC

6.5-inch color liquid
crystal display (LCD)

Exclusive function keysExtension-key block

Front Panel

Rear Panel

USB

Output file data to USB
memory or a USB printer
Image files: PNG, BMP
Setting files: BIN, XML

TG OUT

Tracking generator

(option)

Battery mount

Mount for the battery pack
(battery sold separately)

DC INPUT

Operation with an external
DC power supply
+11 VDC to +17 VDC

PHONE

Earphone jack for

demodulated

AM/FM audio

U3741/3751-1E Mar. ’07

3

4

U3741/3751-1E Mar. ’07

5-minute warm-up time

With the U3741/3751, warm-up time has been reduced to a scant
5 minutes (at an ambient temperature of 20 to 30°C). This short­ened period virtually eliminates pre-warming time as a considera­tion, and permits quick and accurate measurement.

High throughput

This spectrum analyzer delivers data transfer speed superior to that
of its predecessor. While the previous model delivered 875 ms, the
U3741/3751 boasts a speed of 350 ms: double the system through­put

*2

(using the GPIB interface)*3. This faster speed contributes to
a significant reductions to cost of test on production lines and in
similar applications.

Compact Design with High Performance

Our conventional model

U3741/3751

Time

Stable measurement

5

min.

Measuring time

Our conventional model

U3741/3751

Improvements in overall accuracy

Digitized IF sections and innovative circuit technology dramatically
improve absolute power measurement accuracy.

±0.8 dB (10 MHz to 3 GHz: U3741/3751)
±1.0 dB (3 to 8 GHz: U3751)

Standard USB (1.1) interface

Screenshots in BMP or PNG format can easily be sent via USB
external memory. Users can easily store data, and easily paste mea­surement data into reports.

ADC Digital RBW Digital Det

Digital IF Block

RF Input

Up to 2.5 hours*1of nonstop battery-driven operation

The spectrum analyzer uses one of three power systems: AC (100
V/200 V), DC (+11 V to +17 V), or the battery pack. This flexi­bility enables measurement in a variety of applications, whether in
the factory or in the field.

Compact design

At about half the size of its predecessor, this spectrum analyzer
offers a compact design while maintaining the same level of func­tionality. Its form factor gives it portability, enabling it to be used
anywhere.

*1: Typical value at room temperature, without options
*2: Twice that of its predecessor
*3: Sample case where the frequency and span are specified, and the channel power measurement

result is transferred

Extensive array of measurement functions

Measurement functions include Channel Power, Total Power,
Avg Power, OBW, ACP, Spurious measurement, Harmonics mea­surement, IM measurement, Noise/Hz calculation functions,
multi-marker (10 markers), delta marker, peak marker functions,
a channel setting function, and a 3-trace simultaneous sampling
function.