Check And Adjustment - Philips PM 5326 Instruction Manual

4.2.7.
Replacing the RF attenuator, Fig 10
a. Loosen the coupling.
b. Push the shaft a little towards the front.
c. Loosen the nut.
d. Desolder the 2 wires between attenuator potmeter and attenuator switch.
e. Remove the clip.
f. Desolder the output wire.
g. Desolder the small cap.!
h. push the attenuator towards the back and remove it.
For mounting a new RF attenuator perform this procedure in the reverse order
4.3.
CHECK AND ADJUSTMENT
- The limits mentioned in this paragraph are valid only for a newly adjusted instrument and therefore
might deviate from the values as stated in paragraph 1.2. "Technical Data".
-
Adjustment of the instrument is only permitted after a warm-up time of at least 30 minutes a t an
ambient temperature of (+23 t 3 ) ' ~ and when connected to
a
mains voltage of (230
k
11.5) V.
- If not explicitely stated otherwise, the voltage potentials refer to the relevant contact measured against
circuit earth
(I,
).
-
The covers of the cast RF housing can be well removed for check and adjustment. When mounting
the covers the counter-sunk screws must be tightened with equal torque.
- The following abbreviations are used for setting and measuring instruments:
X
-
rh
Ih
m
-
OSC
C
F g
B & K
-
DM
-
50
R
=
Button pressed
=
Button not pressed/unlocked
=
Extreme right-hand position
=
Extreme left-hand position
=
Mid-position
=
Multimeter
=
Oscilloscope
=
Counter,
6
digits
=
Function generator
=
Selective voltmeter (Briill & Kjaer)
=
Sampling voltmeter (AC voltmeter)
=
Digital multimeter
=
variable-ratio isolating transformer
=
50 R terminating resistor