HP 8340B Manual page 270

5-14.
UNLEVELED RF OUTPUT ADJUSTMENTS
Reference
Performance Test:
Maximum Leveled Output Power and Accuracy
Service Section:
RF Section
Description
The A28 SYTM
Driver assembly
is
adjusted to
cause
the
SYTM frequency response to track
the
YO
frequency. When the
YO
frequency
is in
the center of the
SYTM
passband, the
power
loss through the
SYTM
is
minimum;
therefore, SYTM tracking
is adjusted while
viewing
power out versus frequency
and adjusting the SYTM
for
maximum power
out.
In
the multiplying bands, Bands
2,3,
and 4, optimum
biasing of the step recovery diode (SRD, internal to the
SYTM)
is
also required for maximum power
out. Since
this
the case, the
SRD
bias adjustments on the
A24
and
A26 assemblies are also performed
in
this procedure.
OSCILLOSCOPE
0 5 V/GHz
HP 3456A
DIGITAL
VOLTMETER
a ci a a a D a i
aaoaaaaaol
gag
a a a a o a i
Figure 5-40.
Unleveled
RF Output
Adjustments Setup
HP 8340B/41B
Adjustments 5-71