Agilent Technologies 8360 L Series, Service Manual

Page: 272 / 603

5. YO Driv er Gain and Linearity
Description and Procedure
No test equipmen t is required for these adjustmen ts.
F or the gain adjustmen t, the syn thesizer's in ternal D VM monitors the YO lo op error v oltage
at t w o frequencies (p oints B and C in Figure 3-8). When y ou select the gain p oten tiometer
adjustmen t, the syn thesizer displays the dierence in v oltage b et w een p oints B and C as a
\needle" with arrows on either side. By adjusting A13R54 to cen ter the \needle", y ou equalize
the v oltage b et w een the t w o frequency p oints.
The linearit y adjustmen t has t w o parts (eac h of whic h is selected and adjusted similarly to the
gain adjustmen t). The low break p oint adjustmen t equalizes the v oltage b et w een p oints A and
B in Figure 3-8. The high break p oint adjustmen t equalizes the v oltage b et w een p oints C and
D.
Note
Y ou m ust adjust the gain rst; then adjust the break p oints.
Figure 3-8. YO Gain and Linearity Break P oints
1. T urn the syn thesizer on and press 4 PRESET 5. Let it w arm up for at least one hour.
2. Select the A13 gain men u. Press:
4 SERVICE 5
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
Adjust Menu
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
AssyAdj Menu
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
A13 Adj Menu
NNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNNN
A13 Gain Menu
Note
If the follo wing message is display ed: Adjust A13 pot until "locked".,
adjust the p oten tiometer un til the lo c k ed indication is display ed. Con tin ue
with step 3.
3. Select the gain p oten tiometer adjustmen t,
NNNNNNNNNNNNNNNNNNNNNNNNNN
Gain Pot .
4. Adjust A13R54 (see Figure 3-9 ) to cen ter the \needle" on the display .
Agilent 8360 Adjustments
YO Driv er Gain and Linearity
3-15