Thurlby Thandar Instruments TF930 User Manual

TF930

3GHz Universal Counter

INSTRUCTION MANUAL

Table of Contents

Introduction 1
Specification 2
EMC 6
Safety 7
Connections 7
Manual Operation 9
Remote Operation 16
Maintenance 22

Introduction

The TF930 is a portable, battery-operated, universal counter with a large 0.5" 10-digit liquid
crystal display (LCD). The frequency range is from below 0.001Hz to 3GHz and measurement
functions include frequency, period, ratio, pulse width and count.

The instrument uses a high quality temperature compensated internal frequency reference which
has a low aging rate and is stable to within ±1ppm over the full temperature range. Its short
warm-up time allows accurate measurements to be made even under portable battery powered
conditions.

Input A has configurable coupling (AC or DC), input impedance (1MΩ or 50Ω), attenuation
(1:1 or 5:1), threshold (fully variable) and active edge and can be used for frequencies in the

range 0.001Hz to over125MHz. Input B is a nominal 50Ω input for frequencies in the range
80MHz to 3GHz. An External Reference input is provided and changeover from the internal
timebase is automatic when an external reference standard is connected.

For frequency, period and frequency ratio functions the instrument uses a reciprocal counting
technique to provide high resolution at all frequencies. 8 significant digits of answer are produced
in a 1 second measurement time, 9 digits in 10s and 10 digits in 100s with a granularity of less
than 2 counts in the least significant digit.

Indicators show measurement input configuration & function, measurement time & status,
external reference connection, low battery and the units of the measurement which may be Hz,
kHz, MHz, ns, us, ms or s.

The instrument has a USB interface which allows it to be remotely controlled using serial
communication via a computer’s USB port. The remote commands of its predecessor instrument,
the TF830, are compatible with the T F930 command set. The instrument will also automatically
be powered from a standard USB port when connected, whether remote control is in use or not.

The instrument operates from internal rechargeable NiMH batteries which give typically 24 hours
operating life. The universal AC charger supplied will recharge the batteries in less than 4 hours
and can be used for continuous AC operation. Connection to a standard USB port will also power
the instrument (but not charge the batteries).

This instrument is fully compliant with EN61010-1 Safety and EN61326 EMC standards.

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or 50Ω nominal (AC coupled only).

< 500kHz to > 125MHz (50Ω, AC coupled).

AC coupled:

Average ± 50mV (1:1 attenuation) or ± 250mV (5:1 attenuation).

25mVrms to 2.5GHz, 50mVrms to 3GHz.

pp

Input Specifications

Input A

Specification

Configurable options
Input coupling:

Input impedance:
Attenuation:
Active edge:
Low pass filter:
Trigger threshold:

Input Impedance:

Frequency Range:

Trigger Threshold:
DC coupled:

Sensitivity:

AC or DC
1MΩ or 50Ω
1:1 or 5:1
Rising or falling, or width high or low
Filter In (~50kHz cut-off) or Out
Variable thr eshold for both DC and AC coupling

1MΩ//25pF (DC or AC coupled)

< 0.001Hz to >125MHz (1MΩ, DC coupled).
< 30Hz to >125MHz (1MΩ, AC coupled).

0 to 2V (1:1 attenuation) or 0 to 10V (5:1 attenuation).

Sinewave - 15mV
at optimum threshold adjustment.

Input B

Input Impedance:
Frequency Range: < 80MHz to >3GHz.
Sensitivity: Sinewave - 12mV

50Ω nominal (AC coupled).

rms 30Hz to 100MHz, 25mV to 125MHz

rms 80MHz to 2GHz,

Input Signal range: < 0dBm recommended, +13dBm (1Vrms) maximum.

External Reference Input

Input Impedance:
Frequency: 10MHz.
Signal Level:

>100kΩ, AC coupled.

TTL, 3V

to 5Vpp CMOS or 1 to 2Vrms sinewave.

Maximum Input Voltage

Inputs A and B and
External Reference:

Note that the inputs will not be damaged if subjected to an accidental short-term connection to a 50/60Hz
line voltage not exceeding 250V

30VDC; 30Vrms 50/60Hz with respect to earth ground

rms, or 250V DC.

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Measurement Clock:

50MHz.

A Input Frequency Range:

< 0.001Hz (DC coupled) to >125MHz

B input Frequency Range:

80MHz to >3000MHz.

Resolution:

up to 10 digits (see below) or 0.001Hz

A Input Period Range:

8ns to 1000s (DC coupled)

B input Period Range:

333ps to 12.5ns

cycle.

Pulse Width Range:

40ns to 1000s

Averaging:

Automatic within measurement time selected, up to 50 pulses.

averaging. 0.01% for Ratio H:L and Duty Cycle.

Count range:

1 to 9 999 999 999

Minimum pulse width:

8ns

displayed.

Timebase

Internal Reference oscillator: 10MHz TCXO with electronic calibration adjustment.
Oscillator T e mperature Stability: Better than ± 1ppm over rated tem perature rang e.
Initial Oscillator Adjustment Error: < ± 0.2ppm at 21ºC.
Oscillator Ageing Rate: < ± 1ppm first year.
Calibration adjustment range: > ± 8ppm.

Measurement Functions

Frequency (Input A o r Input B)

Period (Input A or Input B)

Resolution: up to 10 digits (see below)

Pulse Width Modes (Input A only)

Functions:

Resolution: 20ns for one pulse; up to 1ns or 10 digits with multiple pulse

Width high, width low, ratio H:L (high time to low time) and duty

Total Count (Input A only)

Frequency Ratio B:A

Resolution: Equal to the resolution of the two frequency measurements.

If the ratio exceeds ten digits, six digits and the exponent are

Measurement Time

Selectable as 100s, 10s, 1s or 0.3s. The instrument displays the average value of the input
signal over the measurement time selected, updated every 2s, 1s, 0.5s or 0.3s respectively. The
hardware captures the count values and continues measuring without any dead time.

Resolution

The displayed resolution depends upon measurement time and input frequency. The basic
resolution of period is 8 digits for every 2 seconds of measurement time. Frequency resolution is
the reciprocal of period resolution. Usable resolution can be reduced by noise at low frequencies.

Accuracy

Measurement accuracy is timebase accuracy + measurement resolution + 2 counts.

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Operating Facilities

Noise Filter

The Filter key controls a low pass filter, with a cut-off frequency of about 50kHz, to assist in
obtaining stable readings at low frequencies.

Hold

Pressing the Hold key will hold the current measured value in the display, with the Hold indicator
on, until the Hold key is pressed again. The measurement continues in the background when
Hold is on. A long press on the Hold key clears old data and restarts the measurement.

Intelligent Power Switching

The unit automatically selects the best available power source of AC adaptor, USB or battery.
Intelligent switching avoids discharging the battery overnight when operated from externally
switched AC power.

A press-to-measure facility allows a quick measurement to be made by pressing a function select
key which will power the instrument up in the corresponding function. The instrument will
automatically switch off 15 seconds after the last key-press.

Remote Control

All capabilities can be controlled remotely and measurements read through a USB port.
The instrument can be powered (but the battery cannot be charged) by the USB host.

Interface: Serial port emulation over USB.
Current consumption: < 95mA (<5mA if AC adaptor power is present)
Command set: Instrument specific. TF830 compatible.

Power Requirements

The instrument has fixed internal rechargeable batteries and is supplied with a universal voltage
external mains adaptor with interchangeable UK, Euro, Australian and US power connectors.

Battery Type: Three 2500mAh NiMH cells.
Battery Operating Life: Typically 24 hours
Low Battery Indicator: ‘Lo Bat' shows in display when approximately 10% of battery life remains.
Recharge Time: < 4 hours
Adaptor Supply range: 85 to 240V, 50 or 60 Hz,
Power consumption: 5W max at DC input to unit; 15VA max at AC adaptor input (charging).

General

Display: 10 digit LCD, 12.5mm high (0.5”). Annunciators show input configuration,

Operating Range: +5°C to +40°C, 20% to 80% RH
Storage Rang e:

operating mode, measurement units and gate time.

–20°C to +60°C

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Environmental: Indoor use at altitudes up to 2000m, Pollution Degree 2
Size: 260mm(W) x 88mm(H) x 235mm(D)
Weight: 950 gms (plus 170 gms AC adaptor)
Electrical Safety: Complies with EN61010-1

EMC: Complies with EN61326

b) EN61000-4-3 (2006) Electromagnetic Field

Performance levels achieved are detailed in the user manual.

EC Declaration of Conformi ty

We Thurlby Thandar Instruments Ltd
Glebe Road
Huntingdon
Cambridgeshire PE29 7DR
England

declare that the:

TF930 3GHz Universal Counter with USB Interface

meets the intent of the EMC Directive 2004/108/EC and the Low Voltage Directive 2006/95/EC.
Compliance was demonstrated by conformance to the following specifications which have been
listed in the Official Journal of the European Communities.

EMC

Emissions: a) EN61326-1 (2006) Radiated, Class B
Immunity: EN61326-1 (2006) Immunity Table 1, referring to:

a) EN61000-4-2 (2009) Electrostatic Discharge

Safety – TF930
EN61010-1 Pollution Degree 2.

Safety – AC Power Adaptor

EN60950-1

CHRIS WILDING
TECHNICAL DIRECTOR

2 October 2012

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Universal Counter

This instrument has been designed to meet the requirements of the EMC Directive 2004/108/EC.
Compliance was demonstrated by meeting the test limits of the following standards:

Emissions

EN61326 (2006) EMC product standard for Electrical Equipment for Measurement, Control and
Laboratory Use. Test limits used (radiated emissions only) were Class B.

Immunity

EN61326 (2006) EMC product standard for Electrical Equipment for Measurement, Control and
Laboratory Use. Test methods, limits and performance achieved are shown below ( requirement
shown in brackets):

a) EN61000-4-2 (2009) Electrostatic Discharge : 4kV air, 4kV contact, Performance B (B).
b) EN61000-4-3 (2006) Electromagnetic Field:

3V/m, 80% AM at 1kHz, 80MHz – 1GHz: Perf ormance B (A) and 1.4GHz to 2GHz:
Performance B (A); 1V/m, 2.0GHz to 2.7GHz: Performance B (A).
Note: The TF930 is a sensitive measuring instrument and, if subjected to a sufficiently
large RF field, will count its frequency. At lower field strengths a measurement might be
disturbed, particularly if the applied signal level is small. This is much more likely to be a
problem with the B input than the A input. In all other respects, the instrument will operate
correctly (Performance A) in fields up to 3V/m.

EMC

Adaptor/Charger

This AC adaptor/charger has been designed to meet the requirements of the EMC Directive
2004/108/EC.Compliance was demonstrated by meeting the test limits of the following standards:

Emissions

EN55022, radiated and conducted Class B.

Immunity

EN55024:1998 + A2:2003. Test methods, limits and performance achieved were:
a) EN61000-4-2 (2009) Electrostatic Discharge : 8kV air, 4kV contact, Performance B (B).
b) EN61000-4-3 (2006) Electromagnetic Field, 3V/m, 80% AM at 1kHz, Performance A (A).
c) EN61000-4-11 (2004) V oltage Interrupt: ½ cycle and 1 cycle, 0% Performance B (B);

25 cycles, 70% and 250 cycles, 0% Performance B (C).
d) EN61000-4-4 (2004) Fast Transient, 1k V peak (AC line), Performance B (B).
e) EN61000-4-5 (2006) Surge, 1kV (line to line), 2kV (line to ground), Performance B (B).
f) EN61000-4-6 (2009) Conducted RF, 3V, 80% AM at 1kHz (AC line only; DC Output

connection <3m, therefore not tested), Performance A (A).

Performance Definitions

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The definitions of performance criteria are:

Performance criterion A: ‘During test normal performance within the specification limits.’
Performance criterion B: ‘During test, temporary degradation, or loss of function or

performance which is self-recovering’.

Universal Counter

This instrument is Safety Class III according to IEC classification and has been designed to meet
the requirements of EN61010-1 (Safety Requirements for Electrical Equipment for Measurement,
Control and Laboratory Use).

This instrument has been tested in accordance with EN61010-1 and has been supplied in a safe
condition. This instruction manual contains some information and warnings which have to be
followed by the user to ensure safe operation and to retain the instrument in a safe condition.

This instrument has been designed for indoor use in a Pollution Degree 2 environment in the
temperature range 5°C to 40°C, 20% - 80% RH (non-condensing). It may occasionally be
subjected to temperatures between +5° and -10°C without degradation of its safety. Do not
operate while condensation is present.

Use of this instrument in a manner not specified by these instructions may impair the safety
protection provided.

All accessible parts will be at the same voltage as the outer of the BNC input sockets. In
particular, note that the shell of the USB connector is galvanically connected to the body of the
BNC inputs and will therefore be at earth ground potential when the USB por t is connected to a
desktop PC. However, to maintain user safety under all other circumstances it is essential that no
input is connected to a voltage above 30Vdc or 30Vrms with respect to earth ground which is
the limit of Safe Extra Low Voltage (SELV) by IEC definition. Note that although the inputs will
withstand short-term accidental connection to an AC line voltage up to 250Vrms, 50/60Hz, users
will be at risk if the instrument 'ground' is connected to such hazardous voltages.

Safety

WARNING!

The instrument shall be disconnected from all voltage sources before it is opened for any
adjustment, replacement, maintenance or repair. Any adjustment, maintenance and repair of the
opened instrument under voltage shall be avoided as far as possible and, if inevitable, shall be
carried out only by a skilled person who is aware of the hazard involved.

Do not wet the instrument when cleaning it.
The following symbols are used on the instrument and in this manual.

Adaptor/Charger

The adaptor/charger supplied has a universal input voltage rating of 100-240VAC, 50/60Hz. It is a
Class II (double insulated) device, fully approved to EN 60950-1 (2001) and UL 60950 (UL listing
E245390).

Direct Current

CAUTION – refer to accompanying documentation.
Damage to the instrument may occur if these precautions are ignored.

meaning that the marked terminal is connected to accessible
conductive parts.

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