Tektronix DM 5010, Instruction Manual

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Operating Instructions —DM 5010
Controls and Connectors
The following list describes the functions of the DM 5010
front-panel controls and connectors. See Fig. 2-3.
FUNCTIONS
(1) DCV
When this button is illuminated, the DM 5010 mea­
sures
d c voltages applied to the front-panel or rear­
interface input connectors. The range used with
this function are: 200 mV, 2 V, 20 V, 200 V, and
1000 V.
OHMS
Illuminating this button selects the resistance mea­
surement mode. Resistances applied to the front­
panel input connectors or the rear-interface input
connections are measured using the 200 Ω, 2 kΩ,
20 kΩ, 200 kΩ, 2 MΩ, and 20 MΩ ranges.
NULL
This function operates with the DM5010 set to
DCV, OHMS, DIODE TEST, ACV, or ACV+DCV
(any range). When the NULL button is illuminated,,
the instrument measures and stores the value of
resistance or voltage across the front-panel or
rear-interface input connectors. This stored offset
is applied to the subsequent measurements and
the results displayed. The value of the offset may
be up to ±100% of the range. When the function in
use is changed or NULL function disabled (NULL
button pressed), the NULL offset is no longer ap­
plied. The stored offset is retained until a new off­
set is set by nulling or until the function in use at
the time of nulling is changed.
WARNING
Use caution when the NULL function is enabled, since
the displayed measurement may not indicate the value
of the voltage applied to the input connectors.
(2) DIODE TEST
Illuminating this button generates a 1 mA de cur­
rent at the front panel or rear interface high input
connector. Using conventional current flow, this
current flows out the high input connector, through
a component connected between the high and low
connectors and into the low connector. The volt­
age developed across the component is measured
and displayed using the 2 V de range.
(3) ACV
When this button is illuminated, the DM 5010 mea­
sures and displays true rms ac voltages. Applied
voltages are internally ac coupled to a rms convert­
er. The ranges used with this function are: 200 mV,
2
V, 20 V, 200 V, and 700 V.
ACV + DCV
When this button is illuminated, the DM 5010 mea­
sures and displays true rms ac voltages elevated to
a dc voltage level. Applied voltages are internally
d c coupled to the rms converter. The ranges used
are: 200 mV, 2 V, 20 V, 200 V, and 700 V.
LOW FREQ RESPONSE
When this button is illuminated and the ACV or
ACV
+ DCV function is active, the instrument aver­
ages 4 measurements and displays the average
value of these measurements. This sequence then
repeats. The function provides a stable readout
when measuring low-frequency ac voltages. It is
specified down to 10 Hz; however, it is usable over
the entire frequency range specified for the
DM 5010.
RANGE
(7) AUTO
When this button is illuminated, range selection is
automatic. At over-range, the DM5010 switches
to the next higher range. If the measured value is
less than 9.5% of the range (for most ranges), the
instrument switches to the next lower range.
STEP ^
Activating this button causes the DM 5010 to in­
crement one range. The range is maintained until
the AUTO button is pressed to activate automatic
range selection or until the range is again incre­
mented. The range is maintained when the function
(DCV, OHMS, DIODE TEST, ACV, ACV + DCV) is
changed, except a change to the OHMS function
selects the highest range. Incrementing while oper­
ating in the highest range selects the lowest range.
TRIGGER MODE
(?) RUN
When this button is illuminated, conversions are
free-running at the selected rate. For conversion
rate selection, refer to FAST.
TRIGGERED
Illuminating this button triggers and displays one
measurement. The next measurement begins
when this function is again activated (button is
pressed, or EXTRIG trigger signal is received). Use
of the EXTRIG triggering requires installation of an
internal jumper by qualified service personnel. The
TRIGGERED button flashes on briefly when the in­
strument
is triggered.
2-4