Tektronix 314 Manual

of 1 cycle or the time between 2 or more events is measu 
red (see Frequency Measurements). A portion of 1 cycle,
or a full cycle is usually displayed when measuring or ob 
serving small portions of a wave train (such as risetime,
pulse duration, and aberrations). When part of a wave
train or waveform that occurs later than the sweep trigger
are to be examined, the X10 position of the SWEEP MAG
switch can be used to expand the center portion of the dis 
play. The effective sweep rate for the expanded portion is
decreased by a factor of 10; therefore, timing measurements
must be divided by 10. Portions of the display to be expand 
ed should be centered with the POSITION control before
switching to the X10 position.
SIGNAL APPLICATION TO VERTICAL INPUT
For most applications, the P6049B, or similar probe, should
be used as an interface between the signal source and the
oscilloscope vertical input. The probe increases the input
resistance of the oscilloscope system to about 10 MΩ and
decreases the effective capacitive loading to about 13.5 pF.
The higher the impedance ratio between the input to the
oscilloscope system and the signal source, the less the cir 
cuit under test is loaded, and the more accurate the measure 
ment. Because of circuit loading considerations, all
measurements should be made at low impedance points in
the circuit being tested.
NOTE
To insure that measurements are accurate, al 
ways compensate the probe before using. To
compensate the probe, touch the probe tip to
the .5 V CAL OUT connector on the 314 front
panel and adjust the compensation for the
best front-corner response to the square wave
signal (set VOLTS/DIV switch to 10m and
TIME/DIV switch to 1 ms).
For applications in which the source, such as the output of
a signal generator, is a coaxial connector, use a coaxial cable
between the oscilloscope and the signal source. In this
application, loading is not a problem; however, to preserve
signal fidelity, the cable impedance should equal the source
impedance and the cable should be terminated in its charac 
teristic impedance at the oscilloscope input.
Use a common-ground return between the signal source and
the oscilloscope. When a probe is used, connect the shortest
possible ground lead near the signal source to avoid a long
signal path to ground.
WA RNING I
If the 314 is powered from an external de source
(not connected to an ac power source) provide
314 Operators
13

Tektronix 314 Specifications

General

Brand	Tektronix
Model	314
Category	Test Equipment
Language	English