Tektronix WFM601, Service Manual

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Performance Verification
WFM 601 - Service Manual
4–17
j. Remove the function generator signal from the WFM 601 REMOTE
connector.
18. Check Serial Receiver Equalization Range
REQUIREMENT – Proper operation with up to 17 dB loss at 135 MHz using
coaxial cable having 1/
√
F
loss characteristics (800 mV launch amplitude).
a. Connect 175 meters (574 ft) of Belden 8281 coaxial cable from the serial
digital signal generator output to the WFM 601 SER A INPUT.
Terminate the remaining side of the loop through with a high frequency
terminator.
b. Select SERIAL A INPUT.
c. Select color bars from the serial digital signal generator.
d. CHECK – that a video waveform appears.
e. Press the WFM 601 EDH DET button.
f. CHECK – that the EDH readout appears onscreen.
g. Push the menu-designated RESET ERRORS button.
h. Allow the instrument to run for at least 2.5 minutes.
i. CHECK – that the Errored Seconds, onscreen, is zero.
j. Press the CLEAR MENU.
k. Move the Belden cable and terminator to the SER B INPUT.
l. Select SERIAL B.
m. Repeat steps d. through j. for the SERIAL B INPUT.
19. Check EXT REF Return Loss
REQUIREMENT – 40 dB to 6 MHz. Power on or off.
NOTE . Return Loss Checks:
The Return Loss Checks only need to be done if repairs have been made on the
Input circuitry.
a. Enter the PRESET menu and select RECALL FACTORY.
b. Connect a precision 50 cable from the spectrum analyzer RF Input to
the RF Output on the lower frequency RF Bridge.