Tektronix 1L20, Инструкция по эксплуатации

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Calibration— Type 1L20
Type 1L20, Serial N o ---------------------------------
Calibration Date_________________________
C alibrator_____ _____ ______ ---------------
□ 1. Preliminary Setup...................................................... Page 6-5.
□ 2. Adjust Dispersion...................................................... Page 6-6.
Adjust C358 for 1 marker/centimeter. (lO M H z/C M
dispersion)
Adjust R368 for 1 marker/2 centimeters. (500 kHz/CM
dispersion)
Adjust C384, C385 for a centered 500 kH z/C M dis­
play.
Check kH z/C M dispersion for ± 3 % accuracy.
Check M H z/C M dispersion accuracy over full range
of the IF CENTER FREQ control for:
± 3 % a t 10 M H z/C M
± 3 % a t 5 M H z/C M
± 5 % a t 2 M H z/C M
± 7 % a t 1 M H z/C M
± 1 0 % at .5 M H z/C M
± 1 5 % a t .2 M H z/C M
0 3. Check Dispersion Linearity........................... Page 6-8.
Check the display in all kHz/CM and M H z/C M posi­
tions for ± 3 % linearity.
0 4. Adjust Resolution............................................... Page 6-8.
Adjust C504, C508, R543, C620, L624 for 100 kHz
resolution.
Check for proper 1 kHz resolution.
0 5. Adjust Center Frequency o f Sweeper.......... Page 6-10.
Adjust R253 (Center Freq Range adjust) so that the
DISPERSION control setting does not affect the M H z/
CM center frequency.
Adjust R368 (kHz/CM Cal adjust) so that the DISPER­
SION control setting does not affect the kHz/CM
center frequency.
0 6. Check IF CENTER FREQ Control Range----- Page 6-10.
DISPERSION
Coarse
(1 0 turn) FINE
1 kHz/CM to 500 kHz/CM > + &
- 2 . 5 MHz
> + &
—50 kMz
.2 M H z/C M to 5 M H z/C M > + &
—25 MHz > + &
lO M H zCM > + &
— 10 MHz
- 1 MHz
0 7. Adjust Phase Lock C ircuit........................... Page 6-11.
Adjust L804 for maximum 1 MHz CAL MARKER OUT
signal.
A pply 1 volt p-p 5 MHz signal to EXT FREQ IN and
adjust R831 (Avalanche Volts adjust) midway between
avalanche and free-run. (Minimum jitter.)
Check for voltage swing from < + 4 volts to >
+ 1 0 volts a t Pin D as FINE FREQ control is rotated
through range. Check for + 7 volts a t Pin D with
FINE FREQ control at 0.
0 8. Check RF CENTER FREQ Calibration and Phase Lock
Check calibration for ± 2 MHz ± 1 % o f dial reading.
Check for phase-locked display through range of
analyzer.
0 9. Adjust Narrowband IF Am plifier Peaking. .Page 6-13.
Adjust L I44, C425, C435, T454, T464, L444 for maxi­
mum 200 MHz signal amplitude.
0 10. Adjust Wide-Band Am plifier Response. . . . Page 6-14.
Adjust LI 34 and Cl 37 for fla t response to 150-250
MHz swept frequency signal.
Adjust L I44 for maximum response to 200 MHz signal.
Adjust L147 for minimum response to 65 MHz signal.
0 11. Check Low-Pass and Bandpass Filters___ Page 6-14.
Check for fla t response and roll-off between 150 and
250 MHz for Bands 2-5, between 175 and 225 MHz
for Band 1.
0 12. Adjust RF Mixers........................................... Page 6-15.
Adjust C l4 and Cl 6 for minimum spurious signal
response.
Adjust C66 for best sensitivity and flatness.
0 13. Check Sensitivity and RF Frequency Range Page 6-16.
Check sensitivity with RESOLUTION control fully-
clockwise for:
—80 dBm on Band 1
—90 dBm on Band 2
—80 dBm on Band 3
—75 dBm on Band 4
—70 dBm on Band 5
A t the same time, check for a signal display a t the
extreme ends o f each band.
0 14. Adjust and Check Dynamic Range............... Page 6-17.
Check LINear display for < 2 6 dB dynamic range.
Adjust LOG display for > 4 0 dB dynamic range
Check SQ LAW display for > 1 3 dB dlnamic range.
0 15. Check Display Flatness................................... Page 6-17.
Check display for < ± 1 .5 dB flatness from 225
MHz to 275 MHz.
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