TTI TF930, TF960 Service Manual

TF930 & TF960

3GHz & 6GHz Universal Counters

SERVICE GUIDE

1

Table of Contents

Specifications 2
Safety 5
General 6
Frequency Calibration 7
C Input Threshold Adjustment 8
Diagnostic Notes 9
Battery replacement 11
Parts List 12

2

Specifications

Input Specifications

Input A

Configurable options
Input coupling:
Input impedance:
Attenuation:
Active edge:
Low pass filter:
Trigger threshold:

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
Var iable thr es hold for both DC and AC coupling

Input Impedance:

1MΩ//25pF (DC or AC coupled)

or 50Ω nominal (AC coupled only).

Frequency Range:

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

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

Trigger Threshold:
DC coupled:

AC coupled:

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

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

Sensitivity: Sinewave - 15mVrms 30Hz to 100MHz, 25mV to 125MHz

at optimum threshold adjustment .

Input B

Input Impedance:

50Ω nominal (AC coupled).
Frequency Range: < 80MHz to >3GHz.
Sensitivity: 12mV

rms 80MHz to 2GHz, 25mVrms to 2.5GHz, 50mVrms to 3GHz.

Maximum Input Signal: < 0dBm recommended, +13dBm (1V

rms) maximum.

Input C (fitted to TF960 only)

Input Impedance:

50Ω nominal (AC coupled) in-band. 250kΩ at DC.

Frequency Range: < 2GHz to >6GHz (typically 1.8GHz to 7.5GHz).
Sensitivity: 25mV

rms (–19dBm) 2GHz to 6GHz.

Maximum Input Signal: < +16dBm (1.5Vrms) recommended. Damage level +25dBm (4V

rms).

External Reference Input

Input Impedance:

>100kΩ, AC coupled.
Frequency: 10MHz.
Signal Level:

TTL, 3V

pp

to 5Vpp CMOS or 1 to 2Vrms sinewave.

Maximum Input Voltage

Inputs A, B, C, and
External Reference:

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

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

rms, or 250V DC.

3

Timebase

Measurement Clock: 50MHz.
Internal Reference oscillator: 10MHz TCXO with electronic calibration adjustment.
Oscillator Temperature Stability: Better than ± 1ppm over rated temper at ure range.
Initial Oscillator Adjustment Error: < ± 0.2ppm at 21ºC.
Oscillator Ageing Rate: < ± 1ppm first year.
Calibration adjustment range: > ± 8ppm.

Measurement Functions

Frequency (Inputs A, B or C)

A Input Frequency Range:

< 0.001Hz (DC coupled) to >125MHz

B input Frequency Range:

80MHz to >3000MHz.

C input Frequency Range:

<2Ghz to >6GHz.

Resolution:

up to 10 digits (see below) or 0.001Hz

Period (Inputs A, B or C)

A Input Period Range:

8ns to 1000s (DC coupled)

B input Period Range:

0.333ns to 12.5ns

C input Period Range:

0.166ns to 0.5ns

Resolution: up to 10 digits (see below)

Pulse Width Modes (Input A only)

Functions:

Width high or low, ratio H:L (high time to low time) or duty cycle.

Pulse Width Range:

40ns to 1000s

Averaging:

Automatic within measurement time selected, up t o 50 pulses.

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

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

Total Count (Input A only)

Count range:

1 to 9 999 999 999

Minimum pulse width:

8ns

Frequency Ratio B:A

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

If the ratio exceeds ten digits, displays six digits plus exponent.

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 f r equency. The basic
resolution of period is 8 digits for every 2 seconds of m easur ement time. Frequency resolution is
the reciprocal of period resolution. Usable resolution can be r educed by noise at low fr equencies.

Accuracy

Measurement accuracy is timebase accuracy + measurement resolut ion + 2 c ounts.

4

Operating Facilities

Noise Filter (Input A only)

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 bac kground 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 batter y 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 measur em ents r ead t hr ough 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: < 100mA (<5mA if AC adaptor power is present)
Command set: Instrument specific. TF830 and TF930 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 m ode, m eas ur em ent units and gate time.
Operating Range: +5°C t o + 40° C, 20% to 80% RH
Storage Range:

–20°C to +60°C

Environmental: Indoor use at altitudes up to 2000m, Pollution Degree 2
Size: 260mm(W) x 88mm(H) x 235mm(D)
Weight: 1050 gms (plus 170 gms AC adaptor)
Electrical Safety: Complies with EN61010-1
EMC: Complies with EN61326