HP 8340B Manual page 222

5-17. RF OUTPUT POWER FLATNESS ADJUSTMENT
9. Set the power meter's CAL FACTOR
oscilloscope for maximum PERSISTENCE and minimum BRIGHTNESS. On the OUT, Press
[SHIFT][GHz] [1] [4] [Hz] [SHIFT][MHz][1] [2] [Hz] [SHIFT][kHz] [2] [2] [Hz] to access Cal
Constant 14.
Refer to Figure 5-62 to determine the effect the following adjustments
have on the flatness of the RF output.
The bandcross points seen on the oscilloscope can be used as a fre-
quency reference for the following adjustments. The frequency of the
bandcross points are, from left to right, 7.0,13.5, and in the case of the
HP 8340B, 20.0 0Hz. The bandcross points are the points at which the
sweep pauses and the power drops to a minimum for an instant.
Adjust Cal Constant 14 for the flattest trace from 2.4 to 9 GHz
Press the OUT's
(BK PT1) for the flattest trace from 9 to 20 GHz.
If adjusting an HP 8340B, press the OUT's [a.] step key to access Cal Constant 16. Adjust Cal
Constant 16 and A27R8 (BK PT2) for the flattest trace from 20 to 26.5 GHz.
Repeat these adjustments until the flattest trace is obtained from 2.4 to the maximum OUT RE
Output frequency.
2.3GHz
HP 8340B/41B
dial to 100%. Press [RECALL][1] on the OUT. Set the
O/o
(~]
step key to access Cal Constant 15 and adjust Cal Constant 15 and A27R4
BREAKPOI NT
POT
1
9GHz
Figure 5-62. Relationship of Flatness Adjustments Diagram
NOTE
NOTE
19GHz
(Cont'd)
206Hz
Adjustments 5-117