1. Veto Readout Electronics-The Big Picture. . .
Cable Legend:
Thin Black = Single Channel Coax
Medium Blue = Multichannel Ribbons or Differntial SCSI lines
Thick Red = VME Bus & Data Stream Thereafter
42 BNC Connectors
Patch Panel With Fan-Out Circuit . . .
84 LEMO or BNC Connectors
Borrowed or Existing
NIM Logic
Sample & Hold
(NIM Bins)
In House or Commercial
Discriminators
Two 34 Pin Header
Connectors
42 LEMO Connectors Each
Redundant
Digital History
Comets
(6U VME)
Commercial VME Scaler
(Joerger VS 64)
VME History Buffer
(Struck SIS3400)
SCSI Connectors
Trigger Logic Board
(9U VME)
Analog History
SCSI Disk & Tape

2. Powering From NIM Backplane (+/- 6, 12, and 24 VDC)
Positive Voltage Regulation
-15 V Voltage Regulation
+Vin
78xx Regulator
+Vout
-24 V in
0.33
0.1
220 47
20 V
Zener
7905 Regulator
-15 V out
2.2 1
-5 V Voltage Regulation
-6 V in
7905 Regulator
-5 V out
2.2 1
All Diodes Are
1N4001 Regulators

3. The Sample & Hold Circuit
560 50
560 + _
200 MHz Sample&Hold
Op-Amp in unity
gain configuration + _ 50 50
LM7171
SH605
Hold
To Comet
Analog Inverter
(very fast op-amp in
gain = -1 configuration)
+5V
Analog Buffer/Line Driver
(very fast op-amp in
unity configuration)
560
Veto In
560 + _
TTL One-Shot
(40 ns delay)
KRC = 1 microsecond
LM6171
DM74LS123 50
+5V + _
High Pass Filter
3dB 2kHz
Fast Comparator
(10 ns response time)
TL3116