Allow data
to
accuise for
atout
Lt)
seconis.
402 stop button or tyming X FSTPCL) CR,
Stun ADC ty deoressing
Move tert and ri.ht cursors until ttey are positioned at the channels
which are at half the counts of the teak channel,
19)
Obtain channel numter cf each cursor Sv denressing button under
Rotary switeh 2 and responding to “PU question with the ADC numter
(L to 4) followed bv a carriase return.
20)
Compute resolution at full width at half maximum:
. €ev at Fukhy) x LOO
> Resolution 2
oc2 xev
21)
Resolutions of 9 to 12% are acceptadle.
Higher resolutions revuire
that the program PM.\ow ce ¢r on and photomultiplier tute adj::stmerts we
made,
Design limits of t he de tector prohibit resolutions of less than
”
ee
E - Photomultistier idiustment
Insert the program diskette into mini Floopy unit.
Type LT 193% I PMADS CR,
System will respond with ?28 at 90,90.
Operator tvpes "G” CR.
5)
Disconnect all tut one signal cable from the photomultiplier tuces of
the detector and follow all instructions in the program.
5)
Increase amplifier gain by a factor of 4.
7)
Acquire a spectrum of each PM tube outrut using program,
137
Adjust ech PM tube gain se that the
Cs peaks overlay gach other asain
following instructions as outlinei in PMADJ,.
3)
9)
a)
If peak heights vary ence all peaks overlay the adjust, the focus of the
PM tubes t2 get the maximum count rate in the Csei37 photo peak area.
Attach all signal cable tc PM tubes,
position and comcute
to 9% as possible.
resolution,
reduce amnlifier gain tc original
Repeat until resolution is as
close