TM 11-6625-524-14-2
OPERATING
INSTRUCTIONS
3-1. General
This section should be read carefully before using
a. Set 115/230 volts switch, on the rear panel,
the voltmeter. It contains information necessary
for the input voltage to be used.
for proper operation of the voltmeter. To achieve
b. Set LINE switch at OFF.
valid readings, proper switch settings are
c. Turn the adjusting screw on the front panel
required. Controls and indicators, with the
meter until the pointer is at SET REF.
function of each, are listed in paragraph 3-3.
Operating procedures are described in paragraph
The controls for the voltmeter are on the front and
3-4. The controls are shown in figures 3-1 and 3-2.
rear panels. Their functions are described in table
Control or indicator
Function
Range selector switch
Selects one of eight voltage ranges.
SET REF control. . .
Adjusts the meter pointer to the reference point with zero
input signal. Should perferably be adjusted on the lowest
range.
A two position ON-OFF switch. Connect AC power to the
LINE
switch
.
.
.
.
.
.
.
.
.
.
voltmeter at the ON position.
Indicates that ac power is applied when lit.
LINE lamp..
A nine pin receptacle which accepts the rf probe connector.
PROBE connector.
Mechanical zero adjust screw (rear panel controls). Provided for mechanical zero adjustment of the meter pointer.
DC OUTPUT jack . . . . . . . . . . . . . . . . . . . . . . . . . . . A tip, ring, sleeve phone-type jack for dc output.
POWER connector . . . . . . . . . . . A three pin receptacle which accepts the power cord connector.
Selects transformer connections for 115 or 230 volts input.
115/230 VOLTS switch
(2) Connect the probe tip to the probe for
direct measurement or the 50-ohm adapter for
a. General. Before operating the voltmeter,
measurements in 50-ohm systems or above 100
check the meter to see if the pointer falls on the
MHz. Above 250 MHz, the probe may be used
SET REF mark. It it does not, turn the SET REF
directly without the adapter.
control until the pointer is exactly over the SET
( 3 ) If the approximate voltage to be
REF mark. At the low end of the 0.001 scale of
measured is known, set the range selector switch
the meter, 100 uv and 200 uv points are provided.
to the appropriate scale. Otherwise, set switch at
These are designated by the small numerals 1 and
3 volts scale and turn switch to lower scales until
2 and should be used only on this range.
a proper meter reading is obtained.
CAUTION
(4) To obtain readings in db, add db meter
Damage to the diode cartridge in the
reading (red scale on meter) to the db setting of
probe may result if the input exceeds 500
the range selector switch.
volts dc or 40 volts peak-to-peak.
b. Measurement Procedure.
(1) Set LINE switch to ON.
