ORTEC 473 - Ge(Li) Mode Walk Test; Fig. 7.3. Test Setup for Nal Mode Walk Test

18
HP 8004A
Rep Rate
1K(CW)
Pulse Width 10 ns (Adjust)
Pulse Del.
0 (CCW)
Amplitude
5 V
Amp. Vernier -
CW
Pulse Polarity -
Neg.
DC Offset
Off
Output
Thru Sig. In i
r
Trigger Output
TEK.
CT 3
TIME PICK OFF
EH 5
nsec
RISETIME
INTEGRATOR
TEK.
bQll
ATTENUATOR
425
DELAY
31 ns
Start
Stop
457
TIME to PULSE HEIGHT
CONVERTER
Range
- .05
CG - 10
Multi - 1
FG
- (Adjust)
Bias
- (Adjust)
Gate - Anti
Strobe - Int.
Pos. Output
RG/62 -V
) 100
(
473
Shaping Mode - Nal
Disc. Mode - C.F.
Disc. Level- 0.050 V(CCW)
NOTE: All cables are OO^coax (RG/58) unless otherwise specified.
Fig. 7.3. Test Setup for Nal Mode Walk Test.
TEK. 485
SCOPE
Ext. Trigger
7. Adjust thR 457 Fine Gain and Bias until a 1-ns change corresponds to a change of 2 divisions on the oscilloscope. This
calibrates the system for 500 ps per major oscilloscope division.
8. Change tiie attenuator in the following sequence while observing the oscilloscope: X5X10, X10, XI.
9. Adjust R32 as necessary so that the 457 output amplitude changes no more than 1000 ps (2 divisions) for the attenuator
changes in step 8.
7.6. Ge(Li) MODE WALK TEST
1. Set up the system as shown in Fig. 7.4. With the attenuator set at XI, adjust the attenuator output for 5 V into 50S7.
? Set the attenuator at X2X5.
.8. Adjust the 457 bias so that the 457 output ampli ude is about 5 V on the oscilloscope.
4. Set the vertical gain of the oscilloscope at 0.5V/division.