Checking And Adjusting; Power Supply; Timing Circuit - Philips PM 5775 Manual

<. CHECKING AND ADJUSTING
The tolerances mentioned are factory tolerances; they apply when the instrument is
readjusted completely.
They may differ from the data given in chapter II.
A summary of adjusting elements is given in chapter IX.
.. POWER SUPPLY
Adjustments should be carried out after a warming up time of approx. 30 min.
..1. Power supply
— Set switch AMPLITUDE IN 50 Q, S4, to position negative (—).
— Check by means of a d.c.-voltmeter the +20 V and —20 V d.c. voltages
(points 10 and 13 respectively on printed-wiring board 1) at nominal mains
voltage.
Permissible tolerance + 1 %.
If necessary, adjust with RV101 and RV102 respectively.
3. TIMING CIRCUIT
3.1. Gate
For checking and adjusting of the gate-function, an auxiliary pulse generator is
required which is triggered externally by the trigger output signal of the sampling
oscilloscope. For this PM 5770 or PM 5775/76 may be used.
— Arrange the measuring set-up shown in Fig. X-1.
— Set the control of the instruments as follows:
Auxiliary pulse generator PM 5775 (PM 5776)
REPETITION TIME, S1 TRIGG. or SINGLE SHOT
DELAY, 82, RV2 20 ns
WIDTH, 83, RV3 200 ns
CONT. GATED, S6 CONT.
SINGLE DOUBLE, $7 SINGLE
NORM. INV., S8 NORM.
DC OFFSET IN 50 2, RV4 OV
AMPLITUDE IN 50 2, $4, RVS FLV