ORTEC 473 - Scintillation Mode Walk Test; Fig. 7.1. Test Setup for Leading Edge Discriminator Mode Calibration

16
HP 8004A
Rep Rate
IK (CW)
Pulse Width
10 ns (CCW)
Pulse Del.
0 (CCW)
Amplitude
5 V
Amp. Vernier -
CW
Pulse Polarity -
Neg.
DC Offset
Off
Output
Thru Sig. In \
r
TEK.
CT 3
TIME PICK OFF
OuliMil
Atten.
Ext. Trigger
TEK.485
SCOPE
(50 (ihiit)
I
TEK,
50L2
ATTENUATOR
X2 X5 X10
473
Shaping Mode - Sclnt.
Disc. Mode - I.E.
Disc. Level - 0.050 V(CCW)
Neg. Output
Pos. Output
(IM)
-O
TEK. 10X Probe
NOTE: All cables are SOU coax (RG/58) unless otherwise specified.
Fig. 7.1. Test Setup for Leading Edge Discriminator Mode Calibration.
12. Monitor oik: o! the negative output BNC connectors with the oscilloscope.
13. Adjust R66 carefully until the 473 output starts to appear.
1 . Repeat ■ "ps 7 through 10 above.
7.4. SCINTILLATION MODE WALK TEST
1. Set up the system as shown in Fig. 7.2.
2. Use X2X5 on the attenuator.
3. Adjust the 457 bias so that the 457 output pulse amplitude is about 5 V on the oscilloscope.
4. Set the vertical gain of the oscilloscope at 1 V/division.
5. Adjust the 457 Fine Gain and Bias controls until a change in delay of 1 ns corresponds to a TV (1-division) change in the
457 output.
6. Set the oscilloscope vertical gain at 0.2V/division.
7. Adjust the 457 Fine Gain and Bias controls until a change in delay of 1 ns corresponds to a 5-division change in the 457
output; this calibrates the system for 200 picoseconds/major division on the oscilloscope.