Fluke 6080A - Steering Gain Adjustment, R221 6 C-19.; Acquisition Oscillator Level Adjustment, R227 6 C-20.; 40-MHz Oscillator Adjustment, L601 6 C-21.

TROUBLESHOOTING AND REPAIR
FREQUENCY SYNTHESIS
Steering Gain Adjustment, R221 6C-19.
TEST EQUIPMENT:
• DVM
REMARKS:
The Steering Gain Adjustment is normally required only when U207 or any associated
components are replaced or when the adjustment has shifted.
PROCEDURE:
The Coarse Loop VCO steering voltage is adjusted to 24V with the Coarse Loop VCO
steering DAC set to full scale.
1. Program the UUT to SPCL 909.
2. Program the UUT to SPCL 943. This Special Function programs all DACs to full
scale.
3. Connect the DVM to measure the voltage between TP8 and ground (TP14).
4. Adjust R221 for 24.00V ± .01V.
5. Program the UUT for SPCL 00. This clears all Special Functions.
Acquisition Oscillator Level Adjustment, R227 6C-20.
TEST EQUIPMENT:
• DVM
REMARKS:
The Acquisition Oscillator Level adjustment is normally required only when U206 or
any associated components have been replaced, or when the adjustment has shifted.
PROCEDURE:
Acquisition Oscillator Level at TP6 is adjusted for 3.54V RMS with the phase locked
loop disabled.
1. Connect TP11 to ground (TP13) with a clip lead.
2. Connect the DVM to measure the AC voltage between TP6 and ground.
3. Adjust R227 for 3.54V RMS ± .1V.
40-MHz Oscillator Adjustment, L601 6C-21.
TEST Equipment:
• Frequency counter
• DVM
6C-28