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Model
2001
MAINTENANCE
Set the oscilloscope vertical gain t o 2V/cm and adjust the
MARKER SlZE control fully clockwise.
The markers
should be approximately 12V peak-to-peak in amplitude.
Set the MARKER SlZE switch t o mid-position and adjust
the oscilloscope vertical gain t o 50mV/cm. The markers
should be approximately 50mV peak-to-peak i n amplitude.
Adjust the MARKERS SlZE control fully counterclockwise
and set the oscilloscope vertical gain t o 100uV/cm. The
markers should be less than 100uV peak-to-peak in ampli-
tude. Set the MARKER SlZE switch t o the down position
and adjust the oscilloscope vertical gain t o 50mV/cm. The
markers should be approximately 50mV peak-to-peak in
amplitude. Set the MARKER SlZE switch to the up posi-
tion.
Positive rectified markers should be present for use
with X-Y recording instruments.
The amplitude will be
dependent on the output impedance of the RF detector
being used.
The amplitude should be adjustable from
approximately 6V maximum t o 1mV minimum with a
detector impedance of 1 meg ohm, or from 0.5V t o 1mV
with a detector impedance of 0 ohms. NOTE: The sweep
width must be decreased or the sweep time increased t o ob-
serve the rectified marker.
MARKER T l L T
Set the MARKER SlZE switch t o the down position and
set the MARKER T I L T switch t o the up position.
While adjusting the MARKER SlZE control throughout its
range, note that the birdy marker is adjustable from a 12V
peak-to-peak vertical marker t o a horizontal marker approxi -
mately equal t o 10% of the horizontal deflections ( 1 cm on a
10cm deflection).
MARKER WlDTH
Return the MARKER T l L T switch t o the down position.
Turn on the 1 MHz markers and adjust the MARKER SIZE
control for approximately a 4cm marker.
Adjust the
CENTER FREQUENCY and SWEEP WlDTH controls to
calibrate the oscilloscope for a 1 MHz sweep width.
Adjust the CENTER FREQUENCY t o center the birdy
zero beat on the oscilloscope center graticule line and note
that the marker width is approximately 400 KHz wide
(each cm equals 100 kHz).
Decrease the MARKER
WlDTH switch one position and note that the marker is
approximately 200 kHz wide.
Decrease the MARKER
WlDTH switch one position and note that the marker is
approximately 100 kHz wide.
Decrease the MARKER
WIDTH
switch to the most narrow position.
The
marker
is now approximately 10 kHz wide.
MARKER ACCURACY
Marker accuracy may be verified by one of several methods.
The first method requires a signal generator and a frequency
counter covering the desired marker frequency. First ad-
just the sweep generator's center frequency to the markers
frequency and the sweep width t o approximately 2 MHz.
Connect the output from the signal generator t o the EX-
TERNAL MARKER I N jack, located on front panel, and
carefully adjust the signal generator for a zero beat with
the internally generated birdy marker. Next, connect the
signal generator's output to the counter and read the signal
generator frequency which is now identical t o the internal
markers frequency. Al!owable error i s 0.005% of the mark-
er frequency.
The second method uses the counter only
but requires the removal of the instrument and marker
module covers. Probe the marker box with the input lead
from the counter until sufficient signal is picked up t o pro-
vide a counter reading. The highest crystal frequency used
is 50 MHz. Markers above this frequency use harmonics of
the crystal frequency. Again the allowable error is 0.005%
of the crystal frequency.
Test equipment for the marker accuracy check
i s
not listed
in the recommended test equipment chart since the require-
ments vary with the method and the specific markers in-
stalled in the unit.
Also, the inheritent stability of the
quartz crystal makes a marker accuracy check unnecessary
in all but the most critical applications.
5.3.14
EXTERNAL PROGRAMMING
External programming inputs are not normally checked on
incoming inspection unless these special functions are to
be used in a particular application. The program input sig-
nals, external controls necessary, and input pin connectors
are covered in Section 3 under Operating Instructions. I f
it
is necessary to check these functions at incoming inspec-
tion, reference can be made t o that section of the manual
for complete set-up instructions.
5.4 MECHANICAL ADJUSTMENT O F FRE-
QUENCY INDICATOR TAPES
Rotate both START and STOP thumb wheels to their
lowest frequency position, turn t o left. Both frequency
indicators must read 0 MHz ~ k 2 MHz when read on the
SWEEP WIDTH frequency scale; if not, proceed as follows:
With reference t o Figure 5-7, disengage IDLER by forcing
IDLER SPRING to a disengaged position. While IDLER is
disengaged, rotate the TAPE DRIVE until the frequency
indicator indicates zero frequency, release the IDLER
SPRING and engage the IDLER. I f the frequency error i s
Model 2001
Set the oscilloscope vertical gain to 2V /cm and adjust the
MARKER SIZE control fully clockwise.
The markers
should be approximately 12V peak-to-peak in amplitude.
Set the MARKER SIZE switch to mid-position and adjust
the oscilloscope vertical gain to 50mV /cm.
The markers
should be approximately 50mV peak-to-peak in amplitude.
Adjust the MARKERS SIZE control fully counterclockwise
and set the oscilloscope vertical gain to 100uV/cm. The
markers should be less than 100uV peak-to·peak in ampli-
tude. Set the MARKER SIZE switch to the down position
and adjust the oscilloscope vertical gain to 50m V fcm. The
markers should be approximately 50mV peak-to-peak in
amplitude. Set the MARKER SIZE switch to the up posi-
tion.
Positive rectified markers should be present for use
with X-Y recording instruments.
The amplitude will be
dependent on the output impedance of the R F detector
being used.
The amplitude should be adjustable from
approximately 6V maximum to lmV minimum with a
detector impedance of 1 meg ohm, or from 0.5V to lmV
with a detector impedance of 0 ohms. NOTE: The sweep
width must be decreased or the sweep time increased to ob-
serve the rectified marker.
MARKER TILT
Set the MARKER SIZE switch to the down position and
set the MARKER TILT switch to the up position.
While adjusting the MARKER SIZE control throughout its
range, note that the birdy marker is adjustable from a 12V
peak-to-peak vertical marker to a horizontal marker approxi-
matey
equal to 10% of the horizontal deflections ( 1 cm on a
10cm deflection).
MARKER WIDTH
Return the MAR KE R TI L T switch to the down position.
Tu rn on the 1 MHz markers and adjust the MA R KE R SI ZE
control for approximately a 4cm marker.
Adjust the
CENTER FREQUENCY and SWEEP WIDTH controls to
calibrate the oscilloscope for a 1 MHz sweep width.
Adjust the CENTER FREQUENCY to center the birdy
zero beat on the oscilloscope center graticule line and note
that the marker width is approximately 400 KHz wide
(each cm equals 100 kHz).
Decrease the MARKER
WIDTH switch one position and note that the marker is
approximately 200 kHz wide.
Decrease the MARKER
WI DTH switch one position and note that the marker is
approximately 100 kHz wide.
Decrease the MARKER
WIDTH
switch to the most narrow position. The marker
is now approximately 10 kHz wide.
MAINTENANCE
MARKER ACCURACY
Marker accuracy may be verified by one of several methods.
The first method requires a signal generator and a frequency
counter covering the desired marker frequency.
First ad-
just the sweep generator's center frequency to the markers
frequency and the sweep width to approximately 2 MHz.
Connect the output from the signal generator to the EX-
TERNAL MARKER IN jack, located on front panel, and
carefully adjust the signal generator for a zero beat with
the internally generated birdy marker. Next, connect the
signal generator's output to the counter and read the signal
generator frequency which is now identical to the internal
markers frequency. Allowable error is 0.005% of the mark-
er frequency.
The second method uses the counter only
but requires the removal of the instrument and marker
module covers. Probe the marker box with the input lead
from the counter until sufficient signal is picked up to pro-
vide a counter reading. The highest crystal frequency used
is 50 MHz. Markers above this frequency use harmonics of
the crystal frequency. Again the allowable error is 0.005%
of the crystal frequency.
Test equipment for the marker accuracy check is not listed
in the recommended test equipment chart since the require-
ments vary with the method and the specific markers in·
stalled in the unit.
Also, the inheritent stability of the
quartz crystal makes a marker accuracy check unnecessary
in all but the most critical applications.
5.3.14
EXTERNAL PROGRAMMING
External programming inputs are not normally checked on
incoming inspection unless these special functions are to
be used in a particular application. The program input sig-
nals, external controls necessary, and input pin connectors
are covered in Section 3 under Operating I nstructions. If
it is necessary to check these functions at incoming inspec·
tion, reference can be made to that section of the manual
for complete set-up instructions.
5.4 MECHANICAL ADJUSTMENT OF FRE-
QUENCY INDICATOR TAPES
Rotate both START and STOP thumb wheels to their
lowest frequency position, turn to left.
Both frequency
indicators must read 0 MHz ±2 MHz when read on the
SWEEP WI DTH frequency scale; if not, proceed as follows:
With reference to Figure 5-7, disengage IDLER by forcing
IDLER SPRING to a disengaged position. While IDLER is
disengaged, rotate the TAPE DRIVE until the frequency
indicator indicates zero frequency, release the
IDLER
SPRING and engage the IDLER. If the frequency error is
5-7
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