HP 436A - Page 79

Adjustments
Model 436A
ADJUSTMENTS
5-22.
POWER
REFERENCE
OSCILLATOR LEVEL ADJUSTMENT
(cont'd)
TYPICAL
CALCULATIONS:
5-12
1.
ACCURACY:
DVM
Measurements:
(HP
3490A
-90
days, 23° C ±
5°
C)
(V
COMP)
±0.0183
(V
1
-V
0
)
±0.0233
(R)
±0.033
Math Assumptions :
EFFECTIVE EFFICIENCY CAL
(NBS):
MISMATCH UNCERTAINTY:
(Source
&
Mount
SWR
<l.05)
2.
MATH
ASSUMPTIONS:
2VCOMP
(V,-Vo)
+ vo2
-v,2
(
4R)
(EFFECTIVE EFFICIENCY)
Assume:
V
0
2
-V
1
2
= (V
1
-V
0
)
2
- (V - V )
2
=
-V
2
+ 2V - V
2
1
0
1
1
0
Want:
v2-v2
0
1
±0.013
±0.53
±0.13
<
±0.73
if
2Vo
(V,
-Vo)
<
<2V
COMP
(V,
-
Vo)
i.e.,
Vo
< < v
COMP
' error is negligable.
V
COMP
-
4 volts.
If
V
0
<
400
µ
V, error
is<
0.013.
(typically
V
0
can
be set
to
<50
µV).
3. Derivation
of
Formula
for
V
1
-
V
0
2V
COMP
(V,
-Vo)+
vo2
-v,2
p =
~~~~~~~~~~~~
RF
(
4R)
(EFFECTIVE EFFICIENCY)
Desired
PRF
=
1mW=10-
3
2V
COMP
(V,
-Vo)+
vo2
-v,2
:.10-
3
=
(4R)
(EFFECTIVE EFFICIENCY)
Let
( 4R) (EFFECTIVE EFFICIENCY)
(10-
3
)
= K
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