Installation guide

Troubleshooting

Troubleshooting Assembly Level Problems

1-46

700 Power Supply

• If the +5.2 V, +15 V, and

−15 V supplies are good on the connector pins indicated:

a. Turn power off to the signal generator.

b. Remove the A16 Frac-N (Option UNJ or Option 506) and ohm the connection between the appropriate

J42 and J10 pins.

— If the connection is good, replace the A16 Frac-N (Option UNJ or Option 506).

(Refer to “A16 Frac-N (Option UNJ or Option 506)” on page 2-38.)

— If the connection is bad, replace the A19 Daughterboard.

(Refer to “A19 Daughterboard” on page 2-44.)

• If the +5.2 V, +15 V, and

−15 V supplies are bad on the connector pins indicated:

a. Check the origin of the supply.

— If the supply voltage is good at the origin, replace the A23 Motherboard.

(Refer to “A23 Motherboard” on page 2-52.)

— If the supply voltage is bad at the origin, troubleshoot the problem using that assembly's

troubleshooting procedure.

701 Loop Gain

• Replace the A16 Frac-N (Option UNJ or Option 506).

702 Tuning Voltage

• If the +32 V,

−5.2 V, and +9 V supplies are good on the connector pins indicated:

a. Turn power off to the signal generator.

b. Remove the A16 Frac-N (Option UNJ or Option 506) and ohm the connection between the appropriate

J42 and J10 pins.

— If the connection is good:

a. Re-insert the A16 Frac-N (Option UNJ or Option 506).

b. Turn power on to the signal generator.

c. Check the 10 MHz signal on the A23 Motherboard at J10 pin 99 using an oscilloscope.

The signal should have a period of 100 ns and an amplitude greater than 1.2 Vp-p.

— If the signal is good, replace the A16 Frac-N (Option UNJ or Option 506).