Pendulum CNT-90 Series User Manual

Performance Check
Additional outputs
(CNT-91R/71B only)
–
Connect a DSO with 50  inputs to the
BNC connectors, one at time.
–
Verify that the four output signals are
sinusoidal and that the voltage is >1Vp-p,
typically 1Vrms.
–
Connect the timer/counter and verify that
the frequency is 10MHz ± 0.01Hz,
5MHz ± 0.005Hz, 1MHz ± 0.001Hz and
0.0MHz ± 0.0001Hz respectively.
Measuring Functions
– Connect a 10 MHz sine wave signal with
approx. 1 V
RMS
amplitude into 50 Ωvia a
power splitter to Input A and Input B, e.g
from 10 MHz Out on the rear panel.
– Recall the DEFAULT settings.
Select the following settings for
the
timer/counter via INPUT A and INPUT B:
–
DC, 50 , Man, 0 V
–
Check that the timer/counter performs the
correct measurement by displaying the
results shown in the “Display” column of
Table 7-7.
–
Select function via MEAS FUNC.
–
Note that the results are rounded off and
very approximate. No tolerances are
given for this test.
–
The CNT-90 and the CNT-91 with
optional RF inputs as well as the
CNT-90XL with its various microwave
converters all require an external RF
source to verify Input C. A simple
functional check can be performed by
connecting a 1 GHz, -10 dBm signal after
selecting Freq C. No other settings need
to be changed.
–
Read 1 GHz on the display and for the
CNT-90XL also the input power level
(about -10 dBm).
Check of HOLD OFF
Function
– Recall the DEFAULT settings.
– Select Period Single A.
Select the following common timer/counter
settings for both Input A and Input B via the
hard menu keys INPUT A and INPUT B:
–
50  impedance.
–
DC coupling.
–
MANual trigger, x1 attenuation.
–
Press SETTINGS and activate Hold Off.
Select Hold Off On and set the Trigger
Hold Off time to the minimum value
20 ns.
–
Connect the rear panel output marked
10 MHz OUT to Input A.
–
Increase the Trigger Hold Off time in
steps by means of the UP cursor key and
note the results:
If Trigger Hold Off time <100 ns the result is
about 100 ns, i.e. the same value as without
Hold Off.
If Trigger Hold Off time >100 ns the result is
about 100 ns + Trig Hold Off time.
–
Connect the signal to Input B, select
Period Single B and repeat the tests
above.
RF Inputs
7-11
USER MANUAL ● CNT 9x Series ● Rev.22 February 2020

Pendulum CNT-90 Series Specifications

General

Brand	Pendulum
Model	CNT-90 Series
Category	Measuring Instruments
Language	English