Tektronix 1L30, Instruction Manual

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Calibration— ‘Type , V0
c. W ith the VERTICAL DISPLAY switch in the LIN posi­
tion and 200 M H z signal ap p lied to the RF INPUT connector,
adjust the G A IN control a n d /o r the Signal G enerator output
for a display am plitude of 6 cm,
d . . Check— Signal am plitude across the 600 Q load re­
sistor at the RECORDER connector should measure between
12 mV and 20 mV.
e. Remove the test oscilloscope probe and the phone plug.
13. Check Video Filter O p e ra tio n
a. Equipment setup is shown in Fig. 6-20.
b. Set the DISPERSION to lO O k H z /c m , the T!M E/C m to
5 ms, uncouple the RESO LUTIO N control and turn one posi­
tion counterclockwise from the fully clockwise position.
c. Adjust the G A IN control so the am plitude of the 200
M H z feedthrough signal is a p p ro xim a tely 5 cm.
d. Turn the V ID E O FILTER switch to the O N position.
e. Check— The video filter circuit should attenuate and
distort the .200 M H z response. See Fig. 6-21.
fig . 6-21. Typical Video Filter integrated display o f 200 MHz RF
signal. Sweep rate 5 ms/cm.
f. Decrease the Tim e/Cm setting to 50 ms and check the
display. The display should return to its original response
curve. There should be no appreciable change in the dis­
play shape with the VID EO FILTER switch on or off, unless
noise is present in the display. Set the VIDEO FILTER switch
to off.
NOTES
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