External Leveling Used With the Optional Step Attenuator
Some external leveling applications require low output power from
the swept signal generator. The swept signal generator automatically
uncouples the attenuator from the ALC system for
al l
external
leveling p oints.
Press
4
POWER LEVEL
5
. Note the display. It shows:
--> ATTEN 0 dB, POWER LEVEL: 0.00 dBm
For example, leveling the output of a 30 dB gain amplier to a
level of
0
10 dBm requires the output of the swept signal generator
to be around
0
40 dBm when leveled. At some frequencies this
level is b eyond the range of the ALC mo dulator alone. If so, the
LOW UNLVLED
warning message is displayed. Inserting 40 dB of
attenuation results in an ALC level of 0 dBm, whichiswell within
the range of the ALC. At 20 GHz, 30 dB attenuation is a b etter
choice as it results in an ALC level of
0
10 dBm. This gives a margin
for AM or other functions that vary the power level.
For optimum display accuracy and minimum noise, the ALC
level should b e greater than
0
10 dBm. This is achieved by using
attenuation equal to the tens digit of output p o
wer. Example:
desired output p ower =
0
43 dBm; use:
--> ATTEN: 40 dB, ALC
0
3 dBm
1.
Press POWER
4
MENU
5
.
2.
Select
NNNNNNNNNNNNNNNNNNNNNNNNNNNNN
Set Atten
4
4
54
0
54
dB(m)
5
.
Hint
To obtain atness corrected p ower, refer to \Creating and Applying
the User Flatness Correction Array" in the \Optimizing Swept Signal
Generator Performance" section.
1-26 Getting Started Advanced
To Next Page
Loading...
Need help?
General
