High Frequency Calibration - HP 3400A Operating And Service Manual

Section V
5-25.

HIGH FREQUENCY CALIBRATION.

5-26. AMPLIFIER GAIN ADJUSTMENT .
The Test Oscillator used in this
procedure should be calibrated
at the end of its output cable.
a. Connect test setup illustrated in Figure 5-2.
b. Set Model 3400A RANGE switch and Test
Oscillator output attenuator to
c. Adjust Test Oscillator output frequency for
400 HZj output voltage for 90% of full scale
as indicated on Model 3400A meter.
d. Switch the Test Oscillator monitor switch to
expand mode and set a convenient reference
level.
e. Change Test Oscillator frequency to 10 MHz.
Adjust Test Oscillator output voltage to main­
tain reference level set in step d.
l.
Adjust C405 (10 MHz ADJUST) on
for 90% full scale as indicated on the Model
3400A meter. Replace right side cover;
if
readjust C405
replacing the cover.
g. Vary oscillator between 3 and 10 MHz; main­
taining reference level set in step d.
ModeJ 3400A meter reading varies below 85%
or above 95% of full scale. repeat step f
until optimum response is obtained between
3 and 10 MHz.
5-27. INPUT ATTENUATOR ADJUSTMENT.
The Test Oscillator used in this
procedure should
at the end of its output cable.
a. Connect test setup illustrated in Figure 5-2.
b. Set Model 3400A RANGE switch and Test
Oscillator output attenuator to 1 volt position.
Adjust Test Oscillator outp u t frequency for 400
c.
Hz, output voltage for
cated on Model 3400A meter.
d. Switch the Test Oscillator monitor switch to
expand mode and set a convenient reference
level.
e. Change Test Oscillator frequency to 100 kHz;
adjust Test Oscillator output voltage to main­
tain reference level set in step d.
Remove Model 3400A bottom cover.
l.
CI02 (I V. 100 KC ADJ) for 90% full scale as
indicated on Model 3400A meter.
5 - 6
001 V position.
O.
A4
board
meter reading varies after
If
the
calibrated
be
full scale as indi­
Adjust
g. Vary oscillator between 100 kHz and 10 MHZj
maintain test oscillator output voltage to
reference level set in step d.
meter reading varies more than ±1% to 1 MHz.
:f:: 2 % from 1 MHz to 2 MHz. ±3% from 2 MHz
to 3 MHz. or ±5% from 3 MHz to 10 MHz. re­
adjust C102 until optimum response is obtain­
ed.
5-28. SECOND ATTENUATOR ADJUSTMENT.
The Test Oscillator used in
this procedure should be
calibrated at the end of its'
output cable.
a. Connect test setup tllustrated in Figure 5-2.
b. Set Model 3400A RANGE switch and Test
Oscillator output attenuator to a 0 . 3 volt
position.
c. Adjust Test Oscillator output frequency for
400 Hz; output voltage for 90% full scale as
indicated on Model 340QA meter.
d. Switch the Test Oscillator monitor switch to
expand mode and set a convenient reference
level.
e.
Change Test Oscillator output frequency to
3 MHZj adjust output voltage to maintain re­
ference level set in step d.
!.
Adjust C303 (10 MC . 3V ADJ) for 90% full
scale as indicated on Model 3400A meter.
g. Vary Test Oscillator between 3 MHz and 10
MHz; maintain test oscillator output voltage
to reference level
3400A meter reading varies below 85% or
above 95% of full scale, repeat steps e and f
until optimum response is obtained between
3 and 10 MHz.
S-29. TROUBLESH O OTING PROCEDURES.
5-30. This section contains procedures designed to
assist in the isolation of maHunctions. These opera­
tions should undertaken only after it has been es­
be
tablished that the difficulty cannot be eliminated
the Adjustment and Calibration Procedures,
graph 5-15. An investigation should also
ensure that the trouble is not a result of conditions
external to the Model 3400A.
5-31. Conduct a visual check of the Model 3400A for
possible burned or loose components, loose connec­
tions. or any other condition which might suggest a
source of trouble.
5-32. Table contains a summary of known pro­
5-5
blems by front panel symptoms.
5-33. Table 5-6 contains procedures which may
used as a guide in isolating malfunctions.
outlined in Table 5-6 are not designed to measure all
Model 3400A
If
Model 3400A
set in step d. If Model
by
Para­
made to
be
be
The checks