TEK U3641 Spectrum Analyzer

Features

The U3641/N is a 3 GHz synthesized spectrum analyzer ideal for applications where portability is a must. With a base unit weight of 15 lbs. and the ability to run from AC, DC or optional battery power sources, the U3641/N has been designed specifically to meet the needs of field installation and maintenance applications. The synthesized local oscillator allows high-precision and high-stability measurements. Furthermore, the unit Features optional resolution bandwidths down to 100 Hz. A fast zero span sweep speed of 50 µs allows characterization of TDMA signals, and its built-in measurement functions allow for easy verification of communication standard compliance.

The U3641/N can be customized for a variety of applications by selecting from a wide range of available options.

The U4941/N/U4342 spectrum analyzers provide the same portability and ruggedness as the U3641/N in a more economical, non-synthesized instrument. These analyzers cover a frequency range of 9 kHz to 2.2 GHz, also making them useful for cellular and PCS communications applications. In addition to functions shared with the U3641/N, the U4941/N/U4342 are well suited for EMI measurements with built-in quasi-peak detector and EMC filters.

Along with functions such as a frequency counter with a 1 Hz resolution and a 20 dB gain preamplifier, these analyzers come standard with measurement functions such as third order intermodulation distortion, percent AM, occupied bandwidth and adjacent channel leakage power. GO-NO GO evaluations of the displayed waveform can also be easily performed using the limit line and PASS/FAIL functions which allow upper and lower limits to be set on the screen.

Using the user-define function, commonly used measurements can be easily assigned to function keys, allowing a user-created custom, easy-to-use menu.

These analyzers are light and compact - 15 lbs. base unit, under 20 lbs. with battery. The easy-to-attach strap allows the analyzer to be carried on the shoulder for transport or during measurements. The rugged construction meets MIL-T-28800 and stands up to the harsh conditions of field use.

Addition of the CDMA Option 60 enables easy one-button measurement of CDMA transmission characteristics including in-band spurious, occupied bandwidth, channel power and adjacent channel power. Measurements are included for both base stations and mobile phones, at cellular and PCS frequencies.

The U3641/U3641/N can operate not only on 100/200 V AC power, but also on +10 to +16 V DC or the optional battery pack. Choose the power source that matches your need for portable flexibility.

The 6 in. color TFT LCD display enhances viewing of complex measurements. A built-in tilt mechanism allows adjusting the viewing angle ±15 degrees to improve visibility and efficiency.

These analyzers are well-suited for computer-based applications. Two PCMCIA memory card slots allow you to store and recall instrument settings and measurements. This data can also be transferred directly to a computer in CSV (comma separated variable) and BMP screen image formats. The memory card slots incorporate a dust-proof shutter and an eject mechanism for reliable operation even in difficult outdoor working conditions.

RS-232C and GPIB ports are also standard. This allows you to print hardcopies of spectrum information and to control the instruments from an external computer as well as send/retrieve data.

Composite video out jacks are standard. The output of these spectrum analyzers can be easily projected for better viewing in meetings or training sessions.

Specifications

Frequency Range -
U3641: 9 kHz to 3 GHz.
U4941/U4342: 9 kHz to 2.2 GHz.

Frequency Readout Accuracy - (Start, Stop, CF, Marker).
U3641/N: ±(marker frequency x frequency reference error + 5% x span + 15% x RBW + 10 Hz).
U4941/N/U4342: ±(span x span accuracy + 0.15 x RBW + 50 kHz).

Count Frequency Marker -
Resolution:
U3641/N: 1 Hz to 1 kHz.
U4941/N/U4342: 1 Hz to 1 kHz.
Count Accuracy:
U3641/N(S/N >25 dB, RBW >3 kHz,
1 kHz < SPAN <200 MHz): ±(marker frequency x frequency reference accuracy + 1 LSD ± 5 Hz).
U4941/N/U4342: (S/N > 25 dB, 50 kHz <
span < 10 MHz, RBW > 100 kHz): ±(marker frequency x frequency reference accuracy + 1 LSD ± 5 Hz).

Frequency Reference Accuracy - ±2 x
10^-6/year ±1 x 10^-5 (at 0°C to 50°C).

Frequency Span -
Range:
U3641/N: 1 kHz to 3.2 GHz, 0 Hz (Zero Span).
U4941/U4342/N: 1 kHz to 2.4 GHz, (Zero Span).
Accuracy:
U3641/N: <±5% (SPAN).
U4941/U4342/N: <±5% (SPAN > 100 kHz).

Frequency Stability -
U3641/N:
Residual FM: <60 Hz p-p/100 ms (ZERO span).
Frequency Drift: <150 Hz/min (SPAN <10 kHz).

Frequency Stability -
U4941/U4342/N:
Residual FM: <3 kHz p-p/100 ms.
Frequency Drift (50 ms to 5 s sweep time): <10 kHz after 30 min. warm-up.

Noise Sidebands -
U3641/N:
20 kHz Offset: <-105 dBc.
10 kHz Offset: <-100 dBc.
U4941/U4342/N: <-100 dBc/Hz at 20 kHz offset.

Resolution Bandwidth (3 dB) -
Range: 1 kHz to 3 MHz, 1-3 sequence.
U3641, Opt. for 100, 300 Hz.
Bandwidth Accuracy:
1 kHz to 1 MHz: <±20%.
3 MHz: <±25%.
Selectivity: <15:1 (60 dB to 3 dB, RBW 1 kHz to 3 MHz).
Bandwidth (6 dB) (U4941/N): 9 kHz, 120 kHz
(conforming to CISPR standard).

Video Bandwidth - 10 Hz to 3 MHz (1-3 step).

Amplitude Range -
U3641: +20 dBm to displayed Average Noise Level.
U3641N: +130 dBµV to displayed Average Noise Level.
U4941/N: +20 dBm to displayed Average Noise Level.

Maximum Input Level (±50 V DC maximum) -
Preamplifier OFF (Input Atten >10 dB):
U3641: +27 dBm.
U3641N: +134 dBµV.
U4941/N: +27 dBm, +134 dBµV.
Preamplifier ON (input atten >10 dB):
U3641: +13 dBm.
U3641N: +120 dBµV.
U4941/N: +13 dBm, +120 dBµV.

Display Range -
Log: 10 x 10 div, 10, 5, 2, 1 dB/div.
Linear: 10% of reference level/div, RBW >3 kHz.
QP Log (U4941/N): 40 dB (5 dB/div).

Reference Level Range (U3641/N) -
Preamplifier OFF (Input Atten 0 dB to 50 dB):
Log: U3641, -64 dBm to +40 dBm;
U3641N, +46 dBµV to +150 dBµV.
Linear: U3641, +141.1 µV to +22.36 V;
U3641N, +198.4 µV to 31.44 V.
Preamplifier ON (Input Atten 0 dB to 10 dB):
Log: U3641, -89 dBm to -25 dBm (0.1 dB
step); U3641N, +21 dBµV to +85 dBµV.
Linear: U3641, +7.934 µV to +12.57 mV;
U3641N, +11.16 µV to 17.68 mV.

Reference Level Range (U4941/U4342/N) -
Preamplifier OFF: Log, -64 dBm to +40 dBm (0.1 step); +46 dBµV to +150 dBµV Linear, +141.1 µV to +22.36 V; 199.5 µV to 31.62 V.
Preamplifier ON: Log, -84 dBm to +10 dBm (0.1 dB step); +26 dBµV to +120 dBµV.
Linear, 14.11 µV to 707.1 mV, 19.95 µV to 1 V.

Input Attenuator Range - 0 to 50 dB
(10 dB step).

Sweep Time -
U3641/N: 50 µs to 1000 s and manual sweep.
U4941/4342/N: 50 ms to 1000 s and manual sweep.

Accuracy - <±5%.

Trigger Mode - Free Run, Single, Video, Ext, TV.

Spectrum Demodulation -
Modulation Type: AM and FM (FM at RBW > 3 kHz).
Audio Output: Speaker and phone jack with volume control.

Displayed Average Noise Level (RBW 1 kHz, VBW 10 Hz) -
Preamplifier OFF:
U3641: -117 dBm + 2.7 f (GHz) dB.
U3641/N: -8 dBµV + 2.7 f (GHz) dB.
U4941/N: -117 dBm + 2.7 f (GHz) dB;
-8 dBµV + 2.7 f (GHz) dB.
Preamplifier ON:
U3641: -135 dBm + 4.3 f (GHz) dB.
U3641/N: -26 dBµV + 4.3 f (GHz) dB.
U4941/N: -132 dBm + 3.3 f (GHz) dB;
-23 dBµV + 3.3 f (GHz) dB.

Gain Compression (1 dB) -
Preamplifier OFF (mixer input level, f >10 MHz):
U3641: >-10 dBm.
U3641/N: >+100 dBµV.
U4941/N: >-10 dBm (mixer input level,
f >10 MHz); >+100 dBµV.
Preamplifier ON (RF input level, f >10 MHz):
U3641 (ATT = 0): >-40 dBm.
U3641/N: >+70 dBµV.
U4941/N: >-40 dBm (RF input level,
f >10 MHz): >+70 dBµV.

Spurious Response (Input Atten 0 dB,f >10 MHz) -
Preamplifier OFF:
Second Harmonic Distortion:
U3641: <-70 dB (-30 dBm input).
U3641/N: <-70 dB (+78 dBµV input).
U4941/N: <-70 dB (-30 dBm input).
Third Order Intermodulation Distortion:
U3641: <-70 dB (-30 dBm input).
U3641/N: <-70 dB (+78 dBµV input).
U4941/N: <-70 dB (-30 dBm input).

Residual Responses (Input Atten 0 dB, f >10 MHz) -
Preamplifier OFF:
U3641: <-100 dBm, 50 Ohm.
U3641/N: <+10 dBµV, 75 Ohm.
U4941/N: <-100 dBm; <+10 dBµV.
Preamplifier ON:
U3641: <-105 dBm, 50 Ohm.
U3641/N: <+5 dBµV, 75 Ohm.
U4941/N: <-115 dBm; <-5 dBµV.

Frequency Response (Input Atten 10 dB, 20°C to 30°C, referenced to 30 MHz,after calibration) -
Preamplifier OFF:
U3641: <±1 dB (100 kHz to 2.7 GHz);
<2 dB (9 kHz to 3.0 GHz).
U3641/N: <±1 dB (100 kHz to 2.7 GHz).
U4941/N: <±1 dB (100 kHz to 2.0 GHz);
<2 dB (9 kHz to 2.2 GHz).
Preamplifier ON:
U4342: <±1 dB (100 kHz to 2.7 GHz).
U3641: <±2 dB (9 kHz to 3.0 GHz).
U3641/N: <±1 dB (100 kHz to 2.2 GHz).
U4941/N: <±1 dB (100 kHz to 2 GHz);
<2 dB (9 kHz to 2.2 GHz).

Calibration Signal Accuracy -
U3641: -20 dBm ±0.3 dB.
U3641/N: +90.5 dBµV ±0.3 dB.
U4941/N: -20 dBm ±0.3 dB; + 90.5 dBµV
±0.3 dB.

(after automatic calibration) -
<±0.5 dB.

Scale Fidelity (after automatic calibration) -
Log: <±1.5 dB/90 dB; <±1 dB/10 dB;
<±0.2 dB/1 dB.
Linear: <±5% of reference level, RBW 3 kHz.

Input Attenuator Switching Accuracy (10 dB reference, 20 dB to 50 dB setting) -
U3641:
100 kHz to 2.7 GHz: <±1.0 dB.
9 kHz to 3.0 GHz: <±1.5 dB.
U3641/N:
100 kHz to 2.2 GHz: <±1.0 dB.
U4941/N:
100 kHz to 2 GHz: <±1.0 dB.
9 kHz to 2.2 GHz: <±1.5 dB.

Resolution Bandwidth Switching Uncertainty (after automatic calibration) -
< ± 1.0 dB at RBW 3 MHz.

RF Input -
Connector: N-type jack.
Impedance:
U3641/U4941/U4342: 50 Ohm (nominal).
U3641/N/U4941/N/U4342/N: 75 Ohm (nominal).
VSWR:
Preamplifier OFF:
100 kHz to 2 GHz: <1.5:1.
9 kHz to 3.0 GHz (2.2 GHz
U3641/N/U4941/U4941/N): <2:1.
Preamplifier ON:
10 MHz to 3.0 GHz (2.2 GHz U3641/N):
<2.5:1.
10 MHz to 2.0 GHz (U4941/N): <2:1.

10 MHz Reference Input -
Connector: BNC jack, rear panel.
U3641/N/U4342:
Impedance: 50 Ohm (nominal).
Input Range: 0 dBm to +16 dBm.
U4941/N:
Impedance: 50 Ohm (nominal).
Input Range: +8 dBm to +16 dBm.

Video Output -
Connector: BNC jack, rear panel.
Impedance: 75 Ohm (nominal), AC coupled.
Amplitude: Approx. 1 V p-p, 75 Ohm (composite video signal).

External Trigger Input -
Connector: BNC jack, rear panel.
Impedance 10 kilohm (nominal), DC coupled.
Trigger level: TTL level.

Gate Input -
Impedance: 10 kilohm (nominal).
Sweep step: During TTL low level.
Sweep continue: During TTL high level.

Phone Output -
Connector: Subminiature monophonic jack, front panel.
Power Output: 0.2 W into 8 Ohm (nominal).

GPIB Interface -
Connector: IEEE-488 bus.
Plotter: HP-GL commands (682-XA).
Printer: PCL commands.

RS-232 -
Connector: D-SUB 9-Pin, rear panel.

Memory Card - Two memory card slots, JEIDA-Ver.4.1, PCMCIA Rel. 2.0, Type 1.

Frequency - 10 MHz.

Frequency Accuracy -
±2 x 10^-8/day.
±1 x 10^-7/year.

Opt. 20 and Opt. 70 cannot be installed simultaneously.

Signal Reception -
Radio access format - TDMA-TDD.
Modulation format: pi/4 DQPSK.
Transmission speed: 384 Kbits/s.
Signal channel: Logic control channel code configuration conforms to RCR STD-28.

Level Measurement Range -
Reception performance:
Preamplifier OFF (Input Atten = 10 dB):
52 dBµV to 107 dBµV.
Preamplifier ON (Input Atten = 0 dB):
16 dBµV to 67 dBµV.
Sweep Trigger Modes: Free Run, Video, ID.

Measurement Functions -
ID List displays: CI, CS-ID, PS-ID, level, time.
ID-MKR: Display of specified signal ID.
Period measurement: Measurement of
specified CS-ID.

Burst Error Rate - The number of error slots/The measured (Set) number.

Level Measurement Operations -
Center value processing.
Average value processing.
Max/min. value processing.

TV Demodulation -
Demodulation type: NTSC, PAL, SECAM.
TV standard: M, B/G, D/K/K', I, L/L'.
Output: Video, sound.

TV Image Demodulation Output -
Connector: BNC jack, rear panel.
Impedance: 75 Ohm (nominal), DC coupled.
Amplitude: Approx. 1 V_p-p, 75 Ohm.

TV Sound Demodulation Output -
Connector: Pin jack, rear panel.
Impedance: 1 kilohm (nominal), AC coupled.

TV Image Signal Input -
Connector: BNC jack, rear panel.
Impedance: 75 Ohm (nominal), AC coupled.
Input Level: About 1 V_p-p.

TV Sound Signal Input -
Connector: Pin jack, rear panel.
Impedance: 1 kilohm (nominal), AC coupled.

Opt. for U3641/N. STD for U4342.

Frequency Range - 100 kHz to 2.2 GHz.

Output Level Range -
0 dBm to -31 dBm, 1 dB steps.
N Version: 105 dBµV to 74 dBµV, 1 dB steps.

Output Level Accuracy -
at 30 MHz, -10 dBm: <0.5 dB.
N Version: at 30 MHz, 95 dBµV: <0.5 dB.

Output Level Flatness -
(at -10 dBm, 30 MHz reference):
100 kHz to 1 GHz: <±0.7 dB.
100 kHz to 2.2 GHz: <±1.5 dB.
N Version (at 95 dBµV, 30 MHz reference):
100 kHz to 1 GHz: <±0.7 dB.
100 kHz to 2.2 GHz: <±1.5 dB.

Output Level Switching Accuracy -
(at -10 dBm reference):
100 kHz to 1 GHz: <±1.0 dB.
100 kHz to 2.2 GHz: <±2.0 dB.
N Version (at 95 dBµV reference):
100 kHz to 1 GHz: <±1.0 dB.
100 kHz to 2.2 GHz: <±2.0 dB.

Output Spurious -
Harmonic: <-20 dBc.
Non-harmonic: <-30 dBc.

Tracking Generator Leakage -
<-95 dBm.
N Version: <-16 dBµV.

Tracking Generator Output -
Connector: N-type jack.
Impedance:
50 Ohm (nominal).
N Version: 75 Ohm (nominal).
VSWR:
(<-10 dBm output): <1.5.
N Version (<-10 dBµV output): <2.0.

(Opt. 78 is included in Opt. 72.)

Channel Setting - Channel setting for VHF, UHF, CATV, BS and CS. Two user tables are available and 99 channels can be registered for each table.

Temperature -
Operating: 0°C to 50°C.
Nonoperating: -20°C to +60°C.

Humidity - 85% or less.

External DC Input -
Connector: XLR 4-Pin.
Voltage range: +10 V to +16 V.
Power consumption: 60 W maximum.

AC Input -
Line voltage: 100 VAC and 200 VAC, auto switching.
Voltage range:
100 V operation: 90 V to 120 V.
220 V operation: 220 V to 240 V.
Line frequency: 50 Hz/60 Hz.
Power consumption: 100 VA maximum.