TB 9-6625-2139-35
(c) VERTICAL MODE TRIGGER SOURCE CH 2 pushbutton to out position
(AN/USM-488).
(d) CH 1 VOLTS/DIV switch to 1.
(e) CH 1 AND CH 2 AC GND DC switches to AC.
(f) A AND B SEC/DIV switches to 10 s.
(g) A TRIGGER A&B INT switch to CH 1 (type 2235).
(11) Connect oscilloscope calibrator CHAN 1 to TI CH 1 using a 50Ω feedthrough
termination.
(12) Set oscilloscope calibrator LEVEL SINE output to 50 kHz and 2.2 divisions of
vertical display on TI.
(13) Set CH 1 VOLTS/DIV switch to 1.
(14) Adjust R479 (fig. 2) while rotating A TRIGGER LEVEL control slowly so that
the A trigger is just able to be maintained (R).
(15) Set CH 1 VOLTS/DIV switch to 50m and adjust A TRIGGER LEVEL control
fully cw.
(16) Set oscilloscope calibrator LEVEL SINE output for 5 divisions of vertical
display on TI.
(17) Set CH 1 VOLTS/DIV switch to .5.
(18) Adjust R434 (fig. 2) so display just solidly triggers on positive peak of signal (R).
(19) Press A TRIGGER SLOPE pushbutton to IN:
and adjust A TRIGGER
LEVEL control fully ccw.
(20) Adjust R435 (fig. 2) so display just solidly triggers on the negative peak of signal
(R).
(21) Connect oscilloscope calibrator CHAN 1 with LEVEL SINE output to one side
of a BNC tee. Connect BNC tee to TI CH 1 using an Xl0 attenuator and a 50Ω feedthrough
termination. Connect the other side of BNC tee to TI EXT INPUT.
(22) Set CH 1 VOLTS/DIV switch to 10m and A TRIGGER A SOURCE switch to
EXT.
(23) Set oscilloscope calibrator LEVEL SINE output for 2.2 divisions of vertical
display on TI.
(24) Adjust A TRIGGER LEVEL control for a stable display.
(25) Set HORIZONTAL MODE switch to B and adjust B TRIGGER LEVEL
control for a stable display.
(26) Set CH 1 VOLTS/DIV switch to .1.
(27) Adjust R627 (fig. 2) so that a display can just be maintained by adjusting B
TRIGGER LEVEL control (R).
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