Instructions

2
Specification
MEASUREMENT FUNCTIONS
Frequency (Range A)
Frequency Range: 3Hz to >125MHz
Resolution: 10
-7
Hz to 100Hz (see below)
Frequency (Range B)
Frequency Range: 80MHz to >3000MHz
Resolution: 1Hz to 10kHz (see below)
Period (Range A only)
Period Range: 8ns to 330ms
Resolution: 10
-7
ns to 1us (see below)
Measurement time
Selectable as 10s, 1s or 0.3s.
Resolution
The displayed resolution depends upon the measurement time and the input frequency. Eight or
nine digits are displayed for a 10 second measurement time. Six, seven or eight digits are displayed
for the shorter measurement times depending on input frequency. Usable resolution can be further
reduced by noise, especially at low frequencies.
Accuracy
Measurement accuracy is the sum of timebase accuracy and measurement resolution plus one
count.
TIMEBASE
Crystal Oscillator Frequency:
10MHz
Initial Oscillator Adjustment Error: ± 2ppm (closed-case adjustment by user)
Oscillator Temperature Coefficient: Typically less than
± 0.3ppm/°C 18°C to 28°C,
± 10ppm –20°C to 70°C
Oscillator Ageing Rate: <± 5ppm/year
OPERATING FUNCTIONS
Press to measure
With the power switch off, pressing any of the function select keys will power the instrument up in
the corresponding function. The instrument will automatically switch off 15 seconds after the last
key-press.
Hold
Pressing the Hold key will stop further measurements being made and the current measured value
will remain in the display, with the Hold indicator on, until the Hold key is pressed again.
Noise filter
The Filter key controls a low pass filter, with a cut-off frequency of about 50kHz, to ensure stable
readings at low frequencies.