HP 85640A, Operating And Service Manual

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2. 600 MHz Level A djustment
13. Calculate the desired attenuation value by adding the current attenuation value to the
attenuation dierence .
desired attenuation = current attenuation value + attenuation dierence
Desired attenuation: dB
14. Select a new value for pad A3U4 using T able 5-5 , based on the desired attenuation
calculated above .
15. Replace the A3 interface assembly top shield. Set the LINE switch to ON.
16.
On the host spectrum analyzer , press 4 PEAK SEARCH 5
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
MARKER DELTA 4 FREQUENCY 5
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
CENTER FREQ . Use the step keys to set the spectrum analyzer to each of the center
frequencies listed in T able 5-6 . At each frequency setting, press 4 PEAK SEARCH 5 and record
the marker amplitude in T able 5-6 for the appropriate frequency . The marker amplitude
should be less than the specication listed.
17. Replace the BNC cable at A3J5 with the W5 cable .
T able 5-5. Attenuation V alues of P ad A3U4
HP P art Number Manufacturer's P art Number*
Attenuation
(dB)
0955-0308 MA T-1 1
0955-0309 MA T-2 2
0955-0310 MA T-3 3
0955-0311 MA T-4 4
0955-0312 MA T-5 5
0955-0313 MA T-6 6
0955-0314 MA T-7 7
*These manufacturer's part numbers are for Mini Circuits Lab , Inc . parts .
P art numbers for other manufacturers' parts may be dierent.
5-10 Adjustment Procedures HP 85640A RF T racking Generator Operation and Service Manual