Adjustment Procedures
2715 Spectrum Analyzer Service Manual 5- 11
15. Adjust R639 (HV) on the Power Supply board for --2750 V ±5V.
The DC level at TP120 should lie between 50V and 250 V.
NOTE. The signal at TP120 is a 20 V triangle waveform with a DC component.
The DC component should lie between 50 V and 250 V after R639 is adjusted.
16. Press UTIL five times to returnthe display to the spectral display mode. Set
INTENSITY fully counterclockwise.
17. Adjust R703 (Z AXIS) on the Power Supply board until the display just
disappears (no beam current).
NOTE. Steps 18 through 21 only apply to instrumentsw ith serialnumbers
B04XXXX or above. For instruments with serial numbers B03XXXX or below,
skip to step 22.
18. With a multimetermeasuring the DC voltage at pin 1 of J1, adjust R705
(GEO) for a voltage measurementof 45 Vdc +1V.
19. Adjust R110 (FOCUS) on the Power Supply board for bestoverall focus.
20. AdjustR 704 (ASTIG)on the P owerSupply board to improve the overall focus.
21. Readjust R110 on the Power Supply board forthe sharpest overall display.
NOTE. Steps 22 through 24 only apply to instrumentsw ith serialnumbers
B03XXXX or below. For instruments with serial numbers B04XXXX or above,
skip to step 25.
22. Set R110 (FOCUS) on the Power Supply board fully clockwise.
23. Adjust R704 (ASTIG) on the Power Supply board for as rounda dot as
possible.
24. Adjust R110 on the Power Supply board forthe sharpest display.
25. Enable the DEFLECTION AMP CAL signal by pressing UTIL521.Press
any menu button to exit the menu.
26. Disable DISPLAYSTORAGE and READOUT, and enable ZERO SPAN.
27. Press SWEEP ↓six times.
28. Adjust VERT POS (R6) at the rear panel to position the top of the square
wave to the top edge of the screen.
29. Adjust TRACE ROT (R7 )at t he rearp anel for a level trace.