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Table of Contents
Introduction 1
Specification 2
Safety 5
Connections 6
Manual Operation 7
Remote Operation 14
Maintenance 20
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 TF930 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.
