TM 11-6625-444-14-2
(13) Disconnect the coax cable (B4) and
the mode switch to MANUAL TRANSFER. (If the
termination (B5) from the adapter (B2) at
DC lamp illuminates, press the TRANSFER RESET
to select AC mode.) Press the PUSH TO RESET
the voltmeter.
button.
(14) Reconnect the coax cable (B4) from
the ac/dc transfer standard. DC OUT terminals
switch to the 1 volt position and the AC/DC
to the adapter (B2) at the voltmeter.
coupling switch to the DC position. Select a
TIME/DIV range of 1 ms.
(15) Transfer back to the DC mode by
pressing the TRANSFER RESET button on the
ac/dc transfer standard. Observe the reading
(6) Adjust the pulse WIDTH and FREQUEN-
indicated on the voltmeter.
CY on the pulse generator to obtain a mark/-
space ratio of 1:19 (0.5 division pulse, 9.5 divi-
sion base line). The pulse amplitude should be
about 3.8 volts peak-to-peak as observed on
the oscilloscope.
NOTE
If the reading indicated by the volt-
meter is different from the initial read-
trol and the oscilloscope TRIGGER LEVEL to ob-
ing (step 9), the new reading now be-
tain a stable display.
comes the reference voltage.
NOTE
(16) If a different reading was obtained in
step (15), it will be necessary to repeat steps
The meter pointer on the ac/dc
( 1 0 ) through (15) until the high crest factor
transfer standard should arrive
(pulse generator) and dc reading (ac/dc transfer
at a balance condition (0 on BAL
standard) agree.
scale).
g. Rms Converter Dc Range Adjustments (A7-
R40), A7-R39, A7-R11)
(8) Transfer the ac/dc transfer standard to
DC by pressing the TRANSFER RESET button.
(1) Connect the equipment as shown in
(9) Observe the reading displayed by the
voltmeter. It should be about 0.8 volt. Record
(2) Select the 2 V range and AC + DC
the value observed.
function on the voltmeter. All other voltmeter
pushbuttons (except POWER OFF/ON) should be
released to the out position.
(10) Press the TRANSFER RESET button on
the ac/dc transfer standard to transfer back to
the AC mode.
(3) Set the dc voltage calibrator (A1) to
1.9000 volts and observe the reading indicated
on the voltmeter.
(11) Disconnect the coax cable (B4) and
termination (B5) from the oscilloscope and
50
connect it to the voltmeter through the adapter
(B2). It will be necessary to first disconnect the
coax cable (B4) that was connected to the a-
NOTE
dapter (B2), at the voltmeter terminals.
An Ac Voltage Calibrator set to 400
Hz may be substituted for the Dc
(12) Adjust A7-R74 until the voltmeter in-
dicates the same reading displayed in step (9).
Voltage Calibrator.
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