LIBRARY OF THE 
 
 UNIVERSITY OF ILLINOIS 
 
 AT URBANA-CHAMPAIGN 
 
 510.84 
 v0 H 
 
 COI 
 
Digitized by the Internet Archive 
 
 in 2013 
 
 http://archive.org/details/recentimprovemen45wier 
 

 
 • 
 
a 32 x 
 
 by hal 
 is : 
 equilateral 1 
 
 distance be • 
 A double <io> 
 the el 
 
 decided t 
 dltlont 
 
 IS BCt 
 
 In 
 for Nui 
 
 a paper 
 Computer i 
 It ' 
 
 this ne 
 
 protn^ 
 
 on the J] [AC 
 
 Improve* . Afte, 
 
 differ 
 
 
 
 t was 
 
 ! .ne 
 
 
 
 •'' 
 
 I 
 
 r s system 
 
 of the TLLIAC 
 
 
system and 8 
 
 Thorenson system will , v 
 Fii. 
 
 read around ratio will 1 
 
 explanation. 
 
 II DESCRIPTION OF T. 
 In 
 
 time following the fl; 
 
 The beam Is first tu* 
 
 Then it Is moved abru 
 
 displaced, leaving tfc 
 
 three mlcrosecc 
 
 output of the 8H 
 
 positive « 
 
 to the spot by 
 
 turning i t oi 
 
 dot, (g) and a daeh, ; 
 
 
 
 dly improved 
 t this 
 
 put at a 
 .m was devised, 
 two microseconds . 
 spot diameter, 
 3m Is left on for 
 la the 
 peak 
 is returned 
 im on or not 
 
 for a 
 be 
 
 noticed that point. 
 
 The height of this principally 
 
 by the amount of c spot, which is 
 
 discharged in the case of a partially determined 
 
 by the collapse of the s] i he first spot. Thus the 
 
 output Information Is partis pots. The truth of this 
 
 statement is further observed fact that with this 
 
 system, it has been found to be possible to cause failures both from dots 
 
to das he 8 ant'. 
 bad ".*ead around 
 
 test memory which le 
 
 ray tubes . This me 
 
 which automo t 
 
 failure. Read around 
 
 •values rise in ste? 
 
 with dots, select in 
 
 each write-in b 
 
 the test ai 
 
 failures. ThiU 
 
 sequence in the 
 
 fails to make a 
 
 read around ratio of I 
 
 the read aroi 
 
 the newly 
 
 regeneration chassis in 
 
 a six position 
 
 sic 
 
 ible test 
 itire raster 
 c tii that address , 
 
 o dash 
 
 Lth 
 memory 
 

 It 
 
 the»3K= tec 
 ThI: 
 test ." 1 
 dot. 
 correct on t 
 
 On th 
 to use this e 
 arouuo and 1 
 nruc'? \ 
 
 failures would _ t 
 
 duri i 
 
 f allure v , one f I 
 
 
 red 
 3 read 
 
 -onditions as 
 •i that 
 ind de 3 dots 
 be the 
 failures. 
 
In order to cla 
 
 gives output signals rhich, d. 
 
 beam is first turned 
 
 a positive ri. 
 
 manner. Only t 
 
 dash to -lot fa J 
 
 checking for failures. 
 
 The 1 
 of the ra: 
 oe on as 
 
 on times ) . Then a 
 boring eig 
 this cas 
 n is the read a 
 addrec 
 
 is selected anc* 
 of the i*ded spot an 
 test proce-ds as t 
 
 a a spot which 
 / after the 
 
 ?es 
 n the following 
 e the 
 \ge of 
 
 ilf 
 
 -am 
 
 in 
 
 as 
 the address 
 ad then the 
 s in half 
 he opposite 
 ed by the routine is 
 
 of the memory heo h 
 
 half of the memory 
 
 tested. Bef j i number n is read in 
 
 from the input tape and prii The tested values of the 
 
 read around ratio thus are nput tape and the 
 
 machine u may test to values as high as 
 
256 in steps oi 
 
 access and s P 82 * 
 
 with the memory speed, tl tba a ' 
 
 memory would ever be 
 
 value of 
 
 the read around 3rt y tubes occurred 
 
 was from 20 to 25- T ras performed on a 
 
 field of dashes, b es iG neighboring 
 
 addresses were from dots tc -be value at which 
 
 no failures -lashes or from 
 
 dashes to dots is be'- oerally no attention 
 
 need be given by the coder ^ 
 
 very severe cases . 
 
 Ill Q! r l Tj ^ 
 
 Pictures 1, 2, i encountered 
 
 in three Williams tube s ' he 
 
 normal Williams syste for the 
 
 Thorenson variation. Fi c system. The 
 
 dq 
 
 most significant set net electron current 
 
 toward the screen as a func 1 ime, since that is more or less the 
 
 quantity sensed at it to the • .It should be emphasized 
 
 that these curves are only «4 probably are accurate 
 
 only in polarity since it is diff mtity directly. The 
 
 curves are more or less se for each peak being 
 
Indicated on the d 
 
 follow the - fj 
 dt 
 
 caused by the input circuit 
 of sign since r^ is sen- 
 Cons-.; cmal 
 Williams system and the ILL] 
 
 thoroughly. In fact, t these 
 
 systems that the hi experimental 
 
 test of the tr: forms check quite 
 
 closely. As yet, lit around ratio results 
 
 except that they a ILLIAC system 
 at first glance both 1 
 
 The advent of the im. tio has led to 
 
 a reconsideration of what occurs on P poor read around ratio. 
 
 It has been concluded that the disc secondaries Is 
 
 much less sever^than had been s ... le read around ratios, 
 
 (on the order of 50}, it Is felt Q voltage at a 
 
 normally char./ed spot is small. The diffl o arise, though, 
 
 is that by 8 ens lug at the firs foil-. on of the 
 sampling beam; jund. At this timo the first 
 result is that th< I ?pot back to its normal 
 equilibrium value. Then a space d. This means that the 
 
 disturbing effect of this rec at the precise time 
 
 that is almost univc casing of the output 
 
 Information from the amplif disturbing influence 
 
is ever to be felt, It tQ 
 
 read around ratio may be int of 
 
 the charged spot may not have e would 
 
 then seem to indicate a 1&ter 
 
 time would be desirable, as enson. 
 
 With the ILLIAC ^ e feut a 
 
 discharging of the second e - d around 
 
 ratio. Since the thi0 B ystem as is 
 
 described above for ely tnat the true 
 Thorenson system v It la interesting to note, 
 though, that the possibility ;.awa and read around ratio 
 
 to fail in the same direction, r dashes, exists. It 
 
 has been observed to be relati direction of failure 
 
 by either changing the sen- la wou i d 
 
 allow the novel possibility of t io failures 
 
 with the same type of )er of tlmes 
 
 also diminishes flaw amplitude. t possible 
 
 to sample the output In such a m avoid both read around 
 ratio difficulties and f la 
 
 With regard to th , it should be mentioned 
 
 that in order to • v dots and dashea at 
 
 the point indicate fche slgnala ao 
 
 negative with respect to t) f strobing. This 
 negative region , f a apace ch arge about the 
 
 first spot ai sampling beam. It therefore 
 
must be rem 
 
 in in ord 
 
 the charginr 
 
 refill and sir 
 
 here than ear lie 
 
 IV EXPSRIMEHTAL 
 
 In order to 
 
 conditions of severe r 
 
 circuit en 
 
 circuit reacted I 
 
 voltage 
 
 dash hut did r 
 
 amplifier delivered 
 
 this circuit it v 
 
 were en< 
 
 fected "by 
 
 vith 
 
 using 
 built. This 
 iive signal when the output 
 sitive excursion of a 
 ntil the 
 
 k. Using 
 ad ratios 
 arlier 
 ved that 
 
 in time. ]> 
 
 they did not fa] nitive peaks on 
 
 normal dote to sense the 
 
 presence of a dot later 1 
 
 In brd the improved read 
 
 around same pulse sequence was 
 
 used as in tl t senn at the normal positive 
 
 dash time. The indicated read Grourv; orer than with the 
 
 normal system- Thi jent is due to the 
 
 sensing time and not t. I beam turn on arrangement or any 
 
special and po>: 
 V CCTOCLU5I0K5 
 
 tn thee 
 ratio is actually du? 
 distribution effects 
 "been "previously su 
 improve the read t 
 time. If the c 
 to dashes, the 
 to the s 
 
 d around 
 re- 
 
 9 had 
 to 
 the sensing 
 x.rged almost 
 h very closely 
 2 form since there 
 
 would be no - oor dots 
 
 and it would be very c ace at any point in 
 
 time. 
 
 The chan 
 actually be 
 its use vould involve 
 the forty r^generatio 
 
 it is felt may 
 he TT.T.TA.C since 
 ,al circuits of 
 
 JMJ/nrh