Filter
Top Products
20. 50 MHz Voltage-Tuned Oscillator Adjustments
DACS Accuracy Check
3. Connect DVM to
A22TP9
and ground lead to
A22TP12.
4. Key in [SHIFT)
[CF
STEP SIZE]
J
0 Hz. If using an HP3456A DVM,
pressISTORE_)aZ,
way,
a,
(STORE)@JY,
then
@El
0
(X-Z)/Y.
If not using an HP
3456A
DVM, note voltage
indication for reference later.
5. Key in
[m]
[CF
STEP SIZE)
J
1023
kHz.
6. If using an HP
3456A
DVM, voltage indication should typically be
be + 10.230
fO.O1O
V de. If not using an HP
3456A
DVM, voltage
indication should be + 10.230
fO.O1O
V
de
plus the indication
noted in step 4. If voltage is within tolerance, proceed to next
step. If voltage indication is incorrect, go to Adjustments 18,
Frequency Control Adjustments, and perform YTO and VT0 DAC
adjustments.
7. On the HP
3456A,
press MATH off.
Positive Supply
8. Key in &ENTER FREQUENCY) 1 MHz, [FREQUENCY SPAN) 1 MHz.
Adjustment
Connect DVM to
AllTP5
and ground lead to Al 1 cover.
9. Key in
ISHIFT)
~CF
STEP SIZE)
J
12 kHz. (CRT annotation should
indicate DACS 12.)
10. Key in (SHIFT)
(MKRW1
N.
(CRT annotation should indicate
VT0 frequency of approximately 28.75 MHz. This corresponds
to a VT0 frequency of 57.5 MHz, since the counter indication is
divided by two.)
11. Adjust All OFFSET
AllRlO
and/or All GAIN
AllR9
for VT0
frequency of 28.750 MHz
f0.005
MHz as indicated by CRT
annotation. See Figure 3-79 for location of adjustment.
50MHr
VOLT!
J
Al 1
1GE-TI
JNED OSCILLATOR
u
Al 1
Figure 3-79. Location of 50 MHz VT0 Adjustments
12. Note DVM indication for reference later.
13. Connect DVM to
AllTPl
(located on All cover).
Adjustments 3-131