Adjustment Procedures - HP 5340A Operating And Service Manual

Model 5340A
Maintenance and Service
POWER SUPPLY ADJUSTMENTS (05340-6001 2)
1.
a. -15V Adjustment. On A28 -15V Regulator board (05340-60022), connect voltmeter to TP2. Connect other
lead to chassis. Adjust potentiometer A28R7 for -15.00 i0.05 volts indication.
b.
potentiometer A29R5 for t15.00 k0.05 volts indication.
-5V RF Supply Adjustment. On A31 -5V Regulator board (05340-60024), connect voltmeter probe to TP2.
C.
Adjust potentiometer A31R9 for -5.00 i0.05 volts indication. A31R9 is near TP1.
-5V Digital Supply Adjustment. On A31 -5V Regulator board (05340-60024), connect voltmeter probe to
d.
TP3. Adjust potentiometer A31R2 for -5.00 i0.05 volts indication. A31R2 is near the front edge of the board
+5V RF Supply Adjustment. On A32 +5V Regulator board (05340-60023), connect voltmeter
e.
Adjustment potentiometer A32R6 for
+5V Digital Supply Adjustment. On A32 +5V Regulator board (05340-60023), connect voltmeter to TP2.
f.
Adjust potentiometer A32R3 for t5.00 i0.05 volts indication. R3 is adjacent to TP2, and near the front
edge of the board.
Time Base Power Supply (t11V) Adjustment (Option 001). On A33 +11V Regulator board (05340-60039),
connect voltmeter to TP1. Adjust potentiometer A33R8 for +11.00 i0.05 volts.
HIGH IMPEDANCE AMPLIFIER ADJUSTMENT (05340-60001)
2.
a. Connect a 608 Signal Generator to "10 Hz to 250 MHz" input BNC on 5340A using a 50 ohm feedthru
termination.
Set 608 to 100 MHz at 100 mV rms. (283 mV p-p) (-7 dBm).
b.
Set 5340A RANGE switch to 10 Hz -250 MHz and resolution switch to 100 Hz.
C.
d. On A3 Input board (05340-60001), adjust potentiometer A3R10 for a stable count.
e. Decrease input signal level and adjust A3R10 for a stable display.
f. Continue to decrease input signal level and adjust A3R10 for maximum sensitivity.
Verify that the 5340A properly measures input signals of 50 mV rms
3. 50Q DIRECT COUNT ADJUSTMENT (05340-60041)
Connect a 608 Signal Generator to the type
a.
-25 dBm (12.6 mV rms) (35.6 mV p-p).
b. Set 5340A RESOLUTION switch to 100 Hz and the RANGE switch to the 10 Hz to 18 GHz position.
Remove the four screws attaching the cover on the A17 (05340-60041) Direct Count Assembly. Verify that
C.
the knurled screw is firmly finger tight, securely holding board in position. Replace cover.
d. Adjust the threshold detector potentiometer A17A1 R22 full counterclockwise. This is accessible through
the front hold in the A17 casting cover.
e. Adjust sensitivity potentiometer A17A1 R11 for a stable display.
f. Decrease signal generator output and again adjust A17A1 R11 for a stable display.
Continue to decrease signal generator output and adjust A17A1 R11 until maximum sensitivity is achieved
h. Increase generator output until a stable reading is displayed.
i.
Rotate threshold detector pofentiometer A17A1 R22 fully clockwise, observing a display of all zeros.
Increase signal generator output by 1 dB from the level obtained in step h.
k. Rotate threshold detector pot$;lhometer A17A1 R22 sufficiently counterclockwise until correct reading is
always displayed.
1. Verify that sensitivity is a t least -32 dBm. If not, perform A22R52 adjustment (step 11).
5-4
Figure 5-2. Adjustment Procedures
N
connector on the 5340A. Set the generator to 100 MHz at
to
less (140 mV
or p-p) (-14