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Model
2001
MAINTENANCE
5.3 PERFORMANCE CHECKS
The following procedure is intended t o ensure that the in-
strument meets its published specifications.
The checks
specified assume that the instrument is equipped with A-2
optionsat 1 MHz, 10 MHz, and 50 MHz. While
it
is possible
t o check the instrument's performance without the use of
harmonic markers, by using suitable external CW sources, a
complete check by this method i s impractical.
5.3.1 PRELIMINARY CHECK
Rotate both START and STOP thumb wheels t o their low-
est frequency position (turn full left).
Both frequency
indicators must read 0 MHz, k2MHz, when read on the
SWEEP WIDTH frequency scale.
(Interpolation on the
Sweep Width scale between 0 and 10 MHz is necessary to
locate + 2 MHz).
Preset controls as follows:
BAND t o 1, SWEEP TIME to
LINE, OUTPUT to +10dBm, MARKER WIDTH t o WIDE,
MODE to CW, the four paddle switches to their extreme
down position, 50 MHz HAR markers to on (in position)
and the remaining markers and MOD off. Set the CENT
FREQ to 250 MHz (left thumb wheel) and connect the
power meter t o the RF out connector. (Ensure the power
meter is on the +10dBm scale).
for 5 minutes. The power meter must read between +9.5
t o +10.5dBm. The calibrating procedure calls for +10dBm
adjustment at 300 MHz.
However, some error must be
allowed for changes due t o ambient operating temperature
and variations between power meters.
5.3.2 FREQUENCY CHECKS
Connect the instrument t o the RF detector and scope as
shown in typical setup Figure 5-4. Set the SWEEP WIDTH
control (right thumb wheel) to 520 MHz and the MODE
switch to n F . Leave the rest of the controls as previously
set in step 5.3.1. Adjust the MARKER SIZE, the scope
vertical, and scope horizontal controls to obtain a pattern
as shown in Figure 5-5. Use DC coupling on both the verti-
cal and horizontal scope inputs. The output voltage from
the detector will be approximately 0.8 volts. A detected
output less than 0.7 volts indicates a defective detector or
an uncalibrated scope. Each 50 MHz marker must fall with-
in rt0.2 cm of each CM line on the scope graticule. This is
equivalent t o a display linearity of 2%. This 2% specifica-
tion is extremely important since all dial accuracy specifica-
tion are directly related t o it. Repeat check on BANDS 2
and 3. I n order t o identify absolute frequencies on bands 2
and 3, an external CW signal can be connected t o
the EXTERNAL MARKER I N connector to identify one
of the 50 MHz harmonic markers. This also verifies the
operation of the external marker circuit.
Turn AC power on and allow the instrument to stabilize
SCOPE
il[l
Figure 5-4. Typical Set-Up
-
-
-
-
:
R F
DETECTOR
Model 2001
5.3 PERFORMANCE CHECKS
The following procedure is intended to ensure that the in-
strument meets its published specifications.
The checks
specified assume that the instrument is equipped with A-2
options at 1 MHz, 10 MHz, and 50 MHz. While it is possible
to check the instrument's performance without the use of
harmonic markers, by using suitable external CW sources, a
complete check by this method is impractical.
5.3
.
1 PRELIMINARY CHECK
Rotate both START and STOP thumb wheels to their low-
est frequency position (turn full left).
Both frequency
indicators must read 0 MHz, ±2MHz, when read
on the
SWEEP WI DTH frequency scale.
(I
nterpolation on the
Sweep Width scale between 0 and 10 MHz is necessary to
locate +2 MHz).
Preset controls as follows:
BAND to 1, SWE EP TI ME to
LINE, OUTPUT to +10dBm, MARKER WIDTH to WI DE,
MODE to CW, the four paddle switches to their extreme
down position, 50 MHz HAR markers to on (in position)
and the remaining markers and MOD off.
Set the CENT
FREQ to 250 MHz (left thumb wheel) and connect the
power meter to the RF out connector. (Ensure the power
meter is on the + 10dBm scale).
Turn AC power on and allow the instrument to stabilize
i
j
WAV5TEttK
RF
~--------~HDETECTOR
MAINTENANCE
for 5 minutes.
The power meter must read between +9.5
to +10.5dBm. The calibrating procedure calls for +1OdBm
adjustment at 300 MHz.
However, some error must be
allowed for changes due to ambient operating temperature
and variations between power meters.
5.3.2 FREQUENCY CHECKS
Connect the instrument to the R F detector and scope as
shown in typical setup Figure 5-4. Set the SWEEP WIDTH
control (right thumb wheel) to 520 MHz and the MODE
switch to
fl
F. Leave the rest of the controls as previously
set in step 5.3.1.
Adjust the MARKER SIZE, the scope
vertical, and scope horizontal controls to obtain a pattern
as shown in Figure 5-5. Use DC coupling on both the verti-
cal a;'ld horizontal scope inputs. The output voltage from
the detector will be approximately 0.8 volts. A detected
output less than 0.7 volts ind icates a defective detector or
an uncalibrated scope. Each 50 MHz marker must fall with-
in ±0.2 cm of each CM line on the scope graticule. This is
equivalent to a display linearity of 2%. This 2% specifica-
tion is extremely important since all dial accuracy specifica-
tion are directly related to
it.
Repeat check on BANDS 2
and 3.
I n order to identify absolute frequencies on bands 2
and
3,
an
external
CW
signal
can be connected to
the EXTERNAL MARKER IN connector to identify one
of the 50 MHz harmonic markers.
This also verifies the
operation of the external marker circuit.
SCOPE
D
ii1
'"
9
',
;
.
''l-
t
~fr
,
.....
_
.
-
"
-
,ft...,t'~<;,
\ ~ti
l
Figure 5-4.
Typical Set-Up
5-3
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