HP 8340B Manual page 22

4-2.
FREQUENCY RANGE AND CW MODE ACCURACY (Cont'd)
i.
Using the up
arrow key, step the center frequency
up
to
2.320500 GHz. Check
the counter
indication at each step.
The
counter should indicate the
DUT start frequency (CF
-
0.0005
GHz)
±
1
Hz ±
the resolution of the counter.
NOTE
The above steps
program
the 20/30 frequency
from 29.0 MHz to 21.0 MHz
in
1 MHz steps. The
last CF step programs the 20/30 to 30
MHz and the
M/N frequency to
180.769231
MHz. This checks the remaining N2 Divider
programming bits.
j.
If
a
significant
frequency error
is evident, note the conditions under which the error occurred
and continue this procedure to determine
if
any
other conditions produce an error.
7.
Check the 20/30
MHz
N1
loop frequencies as follows:
a.
Press
[INSTR
PRESET]. Select
a
step size of 10
kHz
by pressing [SHIFT] [CF] [1] [0] [kHz].
Press
[CW]
and enter
[2] [3] [1] [9]
[.]
[9] [7] [MHz].
b.
Press
[SHIFT] [M1]
to display, from left to right, the
M
divide number, the
N
divide
number, the
M/N Output
frequency, and the
20/30
Output frequency.
c.
Using
the down arrow
key,
step the CW frequency down to 2
319.870000 MHz. Check
the
counter
indication at each step.
The
counter
should indicate the
DUT CW frequency
±
1
Hz ±
the resolution of the counter.
NOTE
The above steps set the output of the
M/N
loop
to 180 MHz where M=26
and N=13.
The
PLL1 VCO
frequency
is
stepped
up
in
100 kHz steps. This
steps the
20/30 frequency
up from 20.03
MHz
in 10
kHz steps to 20.13
MHz. The M/N frequency remains constant and the YO frequency
is
mixed with
a
harmonic (13th) of the M/N
signal.
The resultant
output is
phase compared
to
the 20/30 output. The DUT output frequency must
decrease
by 10
kHz/step
to satisfy
the YO phase lock loop. This checks
the least significant
N1
programming bits.
d.
Select
a
step size of 100 kHz by pressing [SHIFT] [CF] [1] [0] [0] [kHz].
Press the
[CW]
key to
view the CW frequency
in the
[ENTRY DISPLAY]. The CW frequency
should be at
2
319.870000 MHz.
e.
Using the down arrow key, step the CW frequency down
to
2 318.970000 MHz. Check the
counter indication at each
step.
The counter should indicate the
DUT CW frequency
±
1
Hz ±
the resolution of the
counter.
NOTE
The above steps program the 20/30 frequency
from 20.13 up to 21.03 in
0.1
MHz
steps and
checks additional
N1
Divider programming
bits.
HP 8340B/41B
Performance Tests
4-17