Yo Loop Adjustments - HP 8340B Manual

5-8. YO LOOP ADJUSTMENTS

Reference
Performance Test: None
Service Section: Sweep Generator
Description
The YO Loop Adjustment procedure adjusts the sampler drive circuitry and the IF gain.
The YO Loop gain and phase margin adjustment selects the value of resistor A49R18 to place the YO
Loop gain and phase within specified limits. This prevents the YO Loop from oscillating while still
providing sufficient gain in the YO Loop.
The YO frequency adjustment in Paragraph 5-28 must be completed
before these adlustments are made.
lIP 8340B OPT 001
lii
•flII~I.
IlL
~
SWEEP
OUT
HP 8340B/41B
YO Loop
-
Ik.~7~7
osci LLOSCOPE
I!
0
I !
I
Z—AXS 0
L
1)
__
0'
55='
CH A
I NPUT
II
noon
~= ==
noon,.
ZI29E~il
L
~RF
ADAPTER
APC—3.5(f
to
APc—3. 5(f)
ADAPTER
SMA(ni)
to BNc(f)
Figure 5-18.
NOTE
SPECTRUM ANALYZER
0 ====
00 ~
== =0
00 === 00
0
=
CC ±± ~0
moono
O m
00 Z 0
nn
00 ~O
DL ~00OO
0 G-e 0•
RF
NPUT
CC
0
CC
0.0
C
~ 0
OH B
INPUT
A48
10:1 DIVIDER
,ji
PROBE
_______
A
A4BTP
48J
A
50LOAD
~W3B
YO Loop Adjustment Setup
DUT
I
g
g Dfl~
I
D 15
5.
5.
o U
o
5.
J. 5.5.
o
5 5 5
o
5505
C
~ 5505
0000
C
~ 0000
EJDOO
o ~
Ii
Adjustments 5-43