Philips PM5324, Инструкция по эксплуатации

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3.5.5. AMP L I TUDE MODU LATOR , COMPE NSAT I O N O F TH E MODULAT I O N VO LTAG E
- Release a l l range buttons
- Press mode button AM/1 k H z; if necessary, release button WOB.
- Measure the voltage at resistor 634 of unit 1 : maximum L F voltage 5 m Vp_p
- Adjust the compensation voltage to < 5 mV with potentiometer 63 1 on u n i t 1 , if necessary.
3.5.6. HF S I GNAL
3.5.6. 1 . HF ampl itude
- Release a l l buttons
- Termi nate connector H F OUT with 75 n
- Set H F A M P L I TU D E fully clockwise
- Press range button 1 -3
- Measure the voltage at output H F OUT: 50 m V ± 1 m V
- Adjust t h e voltage t o nominal with potentiometer 6 1 2 o n u n it 1 , if necessary.
3 . 5 . 6 . 2 . Frequency
Check the position of the sca le pointer
- Set the pointer approx imately to the middle of the sca le
- Hold the largest knob of control F R EQU E N CY with one hand
- Adjust the smaller k nob - agai nst the resistance of the sl ipping clutch - to the right stop of the sl ipping clutch
- Release the la rge knob and set control F R EQU E NCY to the left stop . The poi nter should n ow be located
on both left pair of marks which a re on the left alongside the sca le; if not, sh :ft the pointer on the scale cord
accordi ng to 3.2.5.2. ( mechanical zero point)
- Set the poi nter with control F R EQU E NCY on the right pa ir of marks, which are on the left alongside the
sca le
- Hold the larger knob of control F R EQU E NCY aga i n
- Set t h e sma l l knob t o t h e left stop o f t h e sl ipping cl utch (electrical zero poi nt) .
Checking the accuracy of the frequency
- Switch on the instrument 30 m i nutes before checking
- Connect a counter, e.g. PM 6630 or PM 6640, to connector H F OUT
- Turn control HF AMP LITUDE fu l l y clockwise
- Check the frequencies according to table 1 .
Readjust, if the tolerancies are not met; use the corresponding ind icated scale .