The SR430 is the first multichannel scaler which combines amplifiers, iscriminators, bin clocks, and data analysis in a single, integrated instrument. With its many features and its easy-to-use menu driven interface, the SR430 simplifies time-resolved photon counting experiments.

The SR430 Multichannel Scaler/Averager can be thought of as a photon counter that counts events as a function of time. A trigger starts the counter which segments photon count data into sequential time bins (upto 32k bins). The width of the bins can be set from 5 ns to 10 ms. The instrument records the number of photons that arrive in each bin.

技术参数:
Signal Input
Bandwidth	DC to 250 MHz
Input impedance	50 Ω
Linear range	±300 mV (at input)
Input protection	±5 VDC, 50 V for 1 µs
Overload recovery	5 ns for <10 µs duration overload
Discriminator
Discriminator range	-300 mV to +300 mV
Resolution	0.2 mV
Slope	Positive or negative
Accuracy	2 mV + 1 %
Min. pulse amplitude	10 mV
Pulse pair resolution	10 ns (typ.)
DISC view output	NIM level into 50 Ω. (There is a 20 ns insertion delay from the signal input to the discriminator output.)
Trigger Input
Impedance	10 kΩ
Threshold	-2.000 V to +2.000 V in 1 mV steps
Slope	Rising or falling
Protection	15 VDC, 100 V for 1 µs
Internal Time Bins
Bin width	5 ns, 40 ns, 80 ns, 160 ns, 320 ns, 640 ns, 1.28 µs, 2.56 µs,...10.486 ms. (10 ns and 20 ns are not available)
Accuracy	1 ns + 20 ppm of bin width
Jitter (RMS)	100 ps + 10 ppm of delay from SYNC/BUSY output (bins are synchronous with SYNC/BUSY output)
Indeterminacy	2.5 ns with respect to trigger input
Insertion delay	45 ns from trigger to first bin. Rising edge of SYNC/BUSY output occurs at beginning of first bin. Signal pulses arriving 25 ns after the trigger will be counted in the first bin.
Externally Clocked Time Bins
EXT BIN CLK input	Rising edge triggers next time bin
Maximum frequency	4 MHz (250 ns minimum bin width)
Minimum time high	100 ns
Minimum time low	100 ns		<, /SPAN>
Insertion delay	Rising edge of SYNC/BUSY output occurs at first rising edge of EXT BIN CLK after trigger. The beginning of the first bin occurs at the same time.
Counters/Accumulation
Bins per record	1k to 16k in 1k increments (1024 to 32,704 including trigger offset)
Max. count rate	100 MHz
Max. count	32,767 per bin per trigger
Records/accumulation	1 to 64k (or free run)
Max. accumulation	32,767 per bin in Add mode, ±16,383 per bin in Toggle or External mode
Add/subtract	Records may be added or toggled (add/subtract on alternating triggers). External subtract input may also control the toggle.
Trigger Rate
Minimum trigger time	Tp = (# of bins × bin width)  + (# of bins × 250 ns) + 150 µs SYNC/BUSY output is high for Tp after each trigger. When SYNC/BUSY returns low, the next record may be triggered. Triggers received while SYNC/BUSY is high are ignored.
Outputs
DISC	NIM level into 50 Ω. Low whenever signal input exceeds discriminator level with the correct slope.
SYNC/BUSY	TTL level. Rising edge is synchronous with first time bin of each record. Remains high until re-armed for next trigger.
BIN CLK OUTPUT	NIM level into 50 Ω. Each transition is a bin boundary. Active only while a record is being acquired. Timing skew relative to DISC out is <2 ns.
TOGGLE	TTL level. Indicates whether the next record will be added to or subtracted from the accumulation. (Internal toggle mode)
TEST	50 MHz NIM output into 50 Ω
AUX1, AUX2	(General purpose analog outputs)
Full scale	±10 V
Resolution	5 mV
Output current	10 mA
Output impedance	<1 Ω
Accuracy	0.1 % + 10 mV
Inputs
SIGNAL	Analog 50 Ω input
TRIGGER	10 kΩ input
BIN CLK INPUT	TTL input. Rising edge triggers next time bin.
ACC. INHIBIT	TTL input, sampled each trigger. If high, causes the current record to be ignored (not accumulated)
SUBTRACT	TTL input, sampled each trigger. If high, causes the current record to be subtracted from the accumulation (in external toggle mode).
General
Interfaces
Data transfer	16k bins in 500 ms
Hardcopy	Screen dumps to Epson compatible dot matrix or LaserJet printers. Plots to HP-GL compatible plotters (serial or IEEE-488.2).
Disk	3.5' MSDOS compatible format, 720k byte capacity. Storage of data and setups.
Power	60 W,100/120/220/240 VAC, 50/60Hz
Dimensions	17' × 6.25' × 16.5' (WHL)
Weight	30 lbs.
Warranty	One year parts and labor on defects in materials and workmanship