Installation guide

Troubleshooting
Troubleshooting Assembly Level Problems
1-63
2000 Ground and PTAT Test
• Using a DVM, measure the voltages on J10 (the PTAT voltage is derived from the ± 15 Vdc):
— If the supply voltages are good on the J10 connector pins indicated:
a. Turn off the power to the signal generator.
b. Remove the A14 Extended Frequency Output (Option 506).
c. Ohm the connection between the appropriate pins of J22 and J10.
— If the connection is good, replace the A14 Extended Frequency Output (Option 506).
(Refer to “A14 Extended Frequency Output (Option 506)” on page 2-34.)
— If the connection is bad, replace the A19 Daughterboard.
(Refer to “A19 Daughterboard” on page 2-44.)
— If the supply voltages are bad on any of the J10 connector pins indicated
a. Check the origin of the supply.
— If the supply voltages are good at the origin, replace the A23 Motherboard.
(Refer to “A23 Motherboard” on page 2-52.)
— If the supply voltages are bad at the origin, troubleshoot the problem using that assembly's
troubleshooting procedure.
2001 Prelevel Loop Test
CAUTION Do not install the A14 Extended Frequency Output (Option 506) with the signal generator
powered up or serious damage to the signal generator may be caused.
• This test checks the Prelevel loop at three frequencies: 4.1 GHz, 5 GHz, and 6 GHz.
— If the test fails:
a. Press the
View Test Info softkey and use the RPG to highlight this test.
b. Press the
View Details softkey to display the failed test frequency.
c. With the signal generator powered on, carefully remove the A14 Extended Frequency Output
(Option 506).
d. Set the signal generator to the failed test frequency (either 4.1 GHz, 5 GHz, or 6 GHz).
e. Connect a spectrum analyzer to J4 of the A14 Extended Frequency Output (Option 506); this is the
output signal of the A16 Frac-N (Option UNJ or Option 506).
f. The signal at J4 should be at the failed test frequency with an amplitude ≥−5dBm.
— If the signal is not present or at the correct level, refer to troubleshooting for the A16 Frac-N
(Option UNJ or Option 506).
— If the signal is present, replace the A14 Extended Frequency Output (Option 506).
(Refer to “A14 Extended Frequency Output (Option 506)” on page 2-34.)
2002 Quadrature DAC Test
• Replace the A14 Extended Frequency Output (Option 506).