Fluke PM6669, Operator'S Manual, Page: 37 / 48

LSD Displayed:
100 ns
(
TIme
<
100 s
)
5
∗
WIDTH
10
9
s
(
TIme
>
100 s
)
NOTE: Triggering on 50% of amplitude will occur only if
the duty factor of the signal is 0.5.
Definitions
LSD Displayed
LSD = Unit value of the least significant
digit displayed. All calculated LSD:s (see section Meas-
uring functions) should be rounded to the nearest dec-
ade (e.g 0.3 Hz is rounded to 0.1 Hz and 5 Hz to 10 Hz)
and cannot exceed the 9th digit.
Resolution
Resolution = smallest increment between
two measuring results on the display, due to the 1 count
error.
Freq A, B, and Period A:
Resolution can be 1 LSD unit
or 2 LSD units.
If;
LSD
∗
Measuring time
FREQ
or
PERIOD
<
10
−
7
the resolution is 2 LSD units (30% probability). Other-
wise resolution is 1 LSD unit (70% probability).
SINGLE Period A and Width A:
Resolution equals 1
LSD unit.
Inaccuracy
Inaccuracy, i.e the relative error, depends on
the following factors:
Resolution
FREQ , PERIOD , or WIDTH
±
relative trigger error
±
relative time base error
Relative trigger error, Freq A, Period A:
±
noise voltage A
(
V
pp
)
signal slope A
(
V
⁄
s
)
∗
meas time
Relative time base error:
±
deviation from 10 MHz
10 MHz
Input specifications
Input-A
Frequency Range:
0 Hz to 160 MHz
Sensitivity,
Sine:
10 mV
RMS
10 Hz to 120 MHz
30 mV
RMS
typically 120 MHz to 160 MHz
Pulse:
30 mV
RMS
0.1 Hz to 120 MHz
Coupling:
AC
Impedance:
1 M
Ω
// 30 pF
Attenuation:
Continously variable in two ranges be-
tween x1 and x400.
Filter:
Switchable 50 kHz low pass noise filter, on Input-A,
with a suppression of 20 dB at 200 kHz.
Trigger Levels:
Three different levels for triggering on
signals with various duty factors, and AUTO.
symmetrical input signals, should be selected forinput
signals with a duty factor of 0.25 to 0.75%.
positive pulses, for input signals with duty factor
<25%.
negative pulses, for input signals with duty factor
>75%.
AUTO Trigger Levels:
The counter will make test set-
tings and automatically selects the best trig level setting.
AUTO requires repetetive signals with a repetition rate
>100 Hz. AUTO is not active in TOTALIZE A measure-
ments.
Trigger Slopes via GPIB Only:
Positive or negative.
Maximum Voltage:
350 V (DC + AC
peak
) between 0
and 440 Hz, falling to 11 V
RMS
at 1 MHz.
Input-B
(option PM 9608B)
Frequency Range:
70 MHz to 1.3 GHz
Coupling:
AC
Operating Input Voltage Range:
10 mV
RMS
to 12 V
RMS
, 70 MHz to 900 MHz
15 mV
RMS
to 12 V
RMS
, 900 MHz to 1.1 GHz
40 mV
RMS
to 12 V
RMS
, 1.1 to 1.3 GHz
Page: 36 SPECIFICATIONS
PM 6669 - OPERATORS MANUAL