Philips PM 5167 - General Check, Adjust Ing and Checking

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3.3. GENERAL CHECK. ADJUSTING AND CHECKING
- The tolerances mentioned in this chapter only apply for a newly adjusted instrument and can deviate from
the values mentioned in chapter 1.2. TECHNICAL DATA .
....
-
Th e instrument only must be adjusted af ter a warming'up of at least 30 minutes at an ambient temperature
of +(23±3) °C.
- The adjustment of Frequency Switch Unit U2 and Controi Unit U5 mu st be performed with completely
closed instrument; if necessary. the instrument must be newly warmed-up after an adjusting procedure.
The remaining units must possibly be performed with el osed instrument; in no case, use an extension p. w.b .
- If
not indicated differently :
-
the voltages, given in this chapter, are measured with respect to the signal earth ( -=1=- )
-
The following abbreviations are used for the various measuring instruments :
L
= open
Q
= oscilloscope with an input impedance of 50 Q *
e.g.
PHILIPS PM 3250
Z = counter e.g. PH I LI PS PM 6620
V = digital voltmeter (d.c .) e.g. PH I LI PS PM 2441
AC·V = AC·milivoltmeter
e.g. PHI LIPS PM 24548
K = distorsiometer
e.g. Hewlett Packard, type 334A
-
G = generator
e.g. PHILIPS PM 5126
50Q = load resistor 50 Q, 3 W
e.g.
PHILIPS PM 9581
1
nF = capacitor 1 nF
*
Measuring cable terminated with 50 Q at the side of the oscilloscope.
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