NEWSLETTER Homebrew Computer Clubjp289tq2478/jp289tq2478_31_0000.pdfComputer Music Interest Group was held on Wednesday evening, March 9, 1977, at the Community Computer Center in

NEW SLETTERH om ebrew

C om pu ter C lubRobert Reiling, E ditor — Post O ffice B ox 626, M ountain View, CA 94042 — Joel Miller, Associate E ditorTypesetting and Graphics donated by LAUREL PUBLICATIONS; Brent Sack, Art Director, 18385 Main Blvd., Los Gatos, CA 95030 (408) 353-3609

COMPUTER MUSIC INTEREST GROUP FORMINGICMOS COOKBOOKlIBO O K R F .V lF .W ^ hv Joh„ Srblllpin g

CM OS C o o k b o o k by D on L an caste r, p u b lish e d by H ow ard Sam s & C o ., Inc.

CMOS has been called the fir s t “hassle fr e e " digital logic fam ily . I t ’s ultra-low in cost and is available in hundreds o f devices fro m a dozen manufacturers. With these w ords, D on Lancaster begins a new book loaded w ith m aterial to bring you up to date on CMOS technology.

Don L ancaster’s first TV typew riter (TVT-1) construction project published in R adio-E lectronics in 1973 convinced me to undertake the construction o f a hom e com puter. When I saw his article, I decided it was possible to build an inexpensive bu t fairly pow erful I/O device. A fter som e re­design fo r a synchronous clock, I bu ilt the TVT-1 and then w ent on to pu t together a hom e com puter system.

D on L ancaster’s new book is a great in­tro duc tion to CMOS and basic logic design. The first chap te r explains CMOS basics and usage reles along w ith o th er handy infor such as breadboarding, tools, sources, etc. C hapter 2 contains a num eric and func­tional index to m ost com m on CMOS ICs. Also given are a series o f data sheets along w ith a general descrip tion o f the device, how to use the device and any know n usage restrictions.

G eneral logic design is well covered in th e th ird chapter; m ultiv ibrator designs are presented in the fou rth . C hapter 5 dis­cusses clocked logic and tw o com m on CMOS clocked flip-flops —the 4013 and the 4027 . This chap te r also covers coun ter designs, touch and prox im ity circuits, syn ­chronizers, D /A converters, phase detec tors and a tuning indicator.

C hapter 6 deals w ith counters and shift registers; C hapter 7 covers CMOS op-am ps, analog switches and phase-locaed loops. The final chapter is titled , “ G etting It All T ogether” and covers several logic designs including a digital w ristw atch, a frequency counter, the b it-boffer Digital Cassette R ecorder and a TVT-4 TV typew riter.

The book is well done and w orth the $9.95 price. My only reservation is tha t m ore logic designs w ith synchronous clocks are needed. □

The organizational m eeting fo r a new C om puter M usic In terest G roup was held on W ednesday evening, March 9, 1977, at the C om m un ity C om puter C enter in M enlo Park.

A ccording to Jim H olliday, provisional chairperson o f th e group, it has been orga­nized to stim ulate serious in terest in this field, bo th from the local hom ebrew com ­p u te r hobbyist com m unity and the musical com m unity . The main focus will be on hardw are and softw are, illum inating the technical “ how -to” fo r the construction o f a nicro com puter-based music synthe-

■ ■■ "M A ' / y l C 1 \ U Z j C L U i j -

G R O W S U P _ _ hv J , „ i

The Santa Cruz C om puter Club is re­laxed, interesting and well organized. A small club w ith abou t 30 m em bers, the Santa Cruz club m eets at 7 pm on th e first Tuesday of every m onth . M eetings are held a t the Mission Hill Ju n io r High School near the in tersection o f Mission and King S treets in Santa Cruz.

Meetings are generally begun w ith a de­m onstration . So far, system s have been dem onstrated by Processor Technology, softw are expert Ed Hall and th e ubiquitous com puter ju n k ie Dan Sokol. N ational Sem idestructor was in last m eeting’s lim e­light w ith a ra ther long-winded b u t in fo r­m ative lecture by Wayde Miricle and John Snyder on N ational’s m icrocom puter pro­ducts, especially PACE. A bou t 30 m em bers a ttended this meeting.

N ext m o n th ’s m eeting will feature a panel discussion analyzing the pros and cons o f various com puter kits. Scheduled to sit on the panel are Dan Sokol w ith his tw o bits on SOL; Ed Hall, the game o f Life wiz; Hank E bertshaeuser o f the now- defunct Santa Cruz Byte Shop and Gary M uhonen, designer o f the PROROM m em ory board. 1'he m ajor areas o f discus­sion will be each k it’s capabilities fo r ap ­plications such as education , te x t editing, graphics, general program m ing, dedicated applications, etc. Also to be discussed are

sizer system . A m utual educational and in­fo rm ation exchange effo rt will be m oun ted fo r this, and the group will be especially in ­terested in providing a forum for those w ho have acquired som e degree o f ex­pertise in the field.

The group will place special em phasis on the needs o f the creative m usician, con­sidering requirem ents a t th e top o f a top - dow n design approach. N ex t m eeting will be a t the same location, W ednesday, March 23, beginning at 7 pm . For fu r th e r details, con tact J im H olliday at ( 4 15)348-0852 .

□

kit quality , ease of construction and avail­ability o f softw are fo r th e in tended use.

For m ore in form ation , con tact club chairman Tom Halvorsen at (4 0 8 )335 -5091

□

g .REDUCED ADMISSION— -----------

M FOR HCC MEMBERS A T FAIRE}

H om ebrew C om puter Club m em bers m ay obtain a reduced adm ission rate fo r The First West Coast C om puter Club Faire b y com pleting the special H om ebrew C om ­p u te r Club Preregistration Form.

T he special H om ebrew C om puter Club preregistration adm ission fee is $7.00 (N orm al Preregistration is $8.00; a t the door $9.00.) This adm ission fee covers ad­mission to all exhibits and official confer­e n c e sessions, A pril 16 and 17, 1977. T he special p reregistration form m ay be obtained a t H om ebrew C om puter Club m eetings during March or by sending a stam ped and self addressed envelope to th e H om ebrew C om puter Club N ew sletter, A tten tio n C om puter Faire, Post O ffice Box 626, M ountain View, CA 94042 . Please allow sufficient tim e fo r Post O ffice hand ­ling. The com pleted P reregistration Form m ust be recieved by T he F irst West Coast C om puter Faire on or before A pril 4, 1977.

□HCC Newsletter/Vol 2, Issue 15/Marcli 16. 1977 one

L I S T

S U R V E Ym T A B U L A T I N G PR O G R A M

The latest com puter survey printed in the Feb 16 Newsletter shows how the club is growing. One problem with the survey is that, while very nicely printed, it takes some time to determ ine which brand is in first, second, . . . , nth place. And even though it doesn’t take very much tim e to find th a t IMSAI-8080 is number one, you have to whip out your calculator to figure what percentage of all computers are IMSA1.

These problems are solved by the program shown in Listing 1. The survey results are not only tabulated but also sorted in order o f greatest to least total items in the class, the percentages are prin­ted out, and to ta l in all classes is shown. A sample com puter run is shown in Listing 2 to dem onstrate how easy it is to get the results of a survey.

The program is w ritten in Altair-com- patible BASIC and is very general. It can be used for any kind o f a survey or even an election. Since the program is so easy to m odify it can be tailored to custom ap­plications. For example, if you are only going to use the program for club com­puter surveys, then the headings are part of the program and no t im put data.

Modifications to the program can extend its usefulness. A nother count vector could be added. Then you can select which count to sort on. Or the list could be sorted by alphabet or by device (all 8080s, etc.). And a little m ath at the end would com pute and report the num ber of com­puters per person and project the num ber o f com puters in the club.

S tatem ent 50 shows the string, tally and pointer vectors all dimensioned to 20. To accom m odate this am ount o f string space it is necessary to insert statem ent 30. The sort-in statem ents 340-390 are a simple bubble sort. This is very crude, bu t since there are only 20 classes the technique is justified. Studies on the subject have shown tha t advanced sorting techniques are not cost effective for less than 100 items.

Note tha t the data is no t sorted at all. A pointer is initialized in lines 310-330 and is sorted instead. This saves moving all o f the string and numeric data around. Finally, the object o f a survey is to find w hat is the predom inant class. Therefore, in line 350 the test is the opposite o f the more typical sort in ascending order.

E ditor’s Note: Ed will supply the source paper tape with docum entation fo r a $2.00 handling charge. Write Edward E. Hughot, Polyhedral System s, 437-A A ldo Ave., Santa Clara, CA 95050; copyright 1977, Edward E. H ughot □

10 12 1 4 1 63 0 5 0 8 0 1 0 0 1 10 1 2 0 1 3 0 1 4 0 1 4 5 1 4 8 1 5 0 1 6 0 1 7 0 1 8 01 9 0 2002 5 0 2 9 0 3 0 0 3 1 0 3 2 0 3 3 0 3 4 0 3 5 0 3 6 0 3 6 5 3 7 0 3 8 0 3 9 0 5 1 0 5 2 0 5 2 2 5 3 0 5 3 2 5 4 0 5 4 2 5 5 0 5 5 2 6 0 0 6 1 0 6 2 0 6 2 2 6 2 3 6 4 0 6 4 2 6 5 0 6 5 2 6 9 0 7 0 0 7 1 0 7 1 2 9 9 9 OK

REM. SURVEYREM. TABULATE AND REPORT SURVEY RES ULTS REM. ED HUGHOT REM. 0 2 / 2 6 / 7 7 CLEAR 9 0 0DIM M $ C 2 0 ) , T C 2 0 ) , P C 2 0 )P R I N T F R E C I )

P R I N T í P R I N T S PRI NT"NAME OF "NAME OF " ENTER

' $" THEN 3 0 0

INPUT I NPUT P R I N T P R I N T 1=0 S = 0INPUT V $ , V I F LEFT S C V S , 1 ) =1 = 1+1MS C I > = V $T ( I ) = V S = S + V GOTO 1 5 0 REM N= IFOR 1=1 TO N PC I ) = I NEXT IFOR 1 = 2 TO N I F T C P C I ) ) < = TCPC I - 1 ) ) U=PC I )P C I > =P C I - 1 )PC I - 1 ) =u GOTO 3 4 0 NEXT IP R I N T í P R I N T : P R I NT î PR I NTPR I NTTAB C 5 ) iP R I N T HI S iPR I NTTAB C 3 1 ) iP R I N T H2SPR I NTT AB C 31 > iP R I N T " T 0 T A L " iPR I NTTAB C 41 ) iP R I N T "PER CENT"FOR 1=1 TO N P R I N T I i PR INTTABC 5 ) i PR I N T M S C P C I ) ) ;Q = T CP CI ) )PR INTTAB C 3 1 > i P R I N T Qi PR I NTT AB C 4 1 ) i P R I N T Ü + 1 0 0 / S NEXT I P R I N TPR I NTTAB C 31 > iP R I N T SEND

DES C R I P T 0 R " i H l $ DATA V A R I A B L E " i H 2 $ DATA A S : V I , V 2 "

THEN 3 9 0

tw o HCC Newsletter/ Vol 2, Issue 15/March 16, 1977

RUN 41 1 8

NAME OF DESCRIPTOR? MANUFACTURER NAME OF DATA VAR IABLE? SYSTEMS IN OPERAT

ENTER DATA AS: VI * V2

? I MSA I - 8 0 8 0 * 43 ? A L T A I R - 8 8 0 0 * 2 2 ? PTC SOL* 5 ? P OLYMORPH I C - 8 8 * 5 ? OTHER 8080 SYSTEMS*19 ? APPLE 6 5 0 2 * 6 ? SHPERE* 1 ? AMI BOARD * 20 ? JOLT * 5? SW TECH PRODUCTS* 4 ? K I M * 4? OTHER 6800 . 6 5 0 - - - * - / 6 5 0 2 SYSTEMS*9 ? F8 * 5 ? ¿ 8 0 * 9 ? 8 0 0 8 * 9 ? T T L * 1 ? B I T S L I C E * 1 ? RCA 1 8 0 2 * 6 ? L S I - 1 1 * 3 ? OTHERS * 5 ? $ * 0

MANUFACTURER SYSTEMS ITOTAL

1 I MSA I - 8 0 80 432 ALT A I R - 8 8 0 0 223 AMI BOARD 204 OTHER 8080 SYSTEMS 195 OTHER 6 8 0 0 / 6 5 0 2 SYSTEMS 96 ¿80 97 8 0 0 8 98 APPLE 6502 69 RCA 1802 610 PTC SOL 511 P0LYM0RPH1C-88 512 JOLT 513 F8 514 OTHERS 515 SW TECH PRODUCTS 416 KIM 417 L S I -11 318 SHPERE 119 TTL 120 B I T S L IC E 1

1 82

OK

■ E m P U T

■'OUTPUT

N OPERATION PER CENT

23 . 6 2 64 1 2 . 0 8 7 9 10 . 9 8 9 10 . 4 3 9 6 4 .9 4 50 6 4 .9 4 50 6 4 .9 4 50 6 3 . 2 9 6 7 3 . 2 9 6 7 2 . 74 72 5 2 . 74 72 5 2 . 74725 2 . 74 72 5 2 . 7 4 72 5 2 .1 9 78 2 .1 9 78 1 . 6 4 8 3 5 . 5 4 9 4 5 1 . 5 4 9 4 5 1 .5 4 9 4 5 1

HCC Newsletter/Vol 2, Issue 15/March 16, 1977 three

— — = A n impressive list o f exhibitors have— taken display space at The First West Coast

S S F A I R E ’S EXH IBTORS LIST BBS hibitors’ booths were rented, according toC R Q W I ^ C F d T T ’ inform ation obtained by the Homebrew

A uditorium April 16th and 17th. A kick- off banquet will be held April 15th at the St. Francis Hotel. □

C O M M I T T E D E X H I B I T O R S Ma r ch 6, 1 9 7 7

6 5 0 2 P R O G R A M E X C H A N G E A C M , B A Y A R E A A C T I O N A U D I O E L E C T R O N I C S A D V A N C E D M I C R O C O M P U T E R P R O D S A L P H A M I C R O T E C H N O L O G Y A N D E R S O N - J A C O B S O N , INC.A P P L E C O M P U T E R SB E N D E R P U B L I C A T I O N S , N C E N & S C E NB O A R D B Y T E R SES CONB Y T E M A G A Z I N E B Y T E S H O P O F P A L O A L T O B Y T E S H O P S O F A R I Z O N A B Y T E , INC.C A L I F O R N I A B U S I N E S S M A C H I N E S C E N T E R F O R S T U D Y O F F U T U R E C O M P T E KC O M P U T A L K E R C O N S U L T A N T S C O M P U T E R D E C I S I O N S M A G A 7 I N E C O M P U T E R KI TS , INC.C O M P U T E R M A G A Z I N E C O M P U T E R R O O M O F S A N J OS E C O M P U T E R S T O R E O F S A N F R A N . C R E A T I V E C O M P U T I N G M A G A Z I N E C R O M E M C OD A T A T E R M I N A L S & C O M M U N I C A T I O N SD A V I S L A B O R A T O R I E SD A Y T O N A S S O C I A T E SD I G I T A L G R O U PD I G I T A L R E S E A R C HD I G I T A L S Y S T E M SD I L I T H I U M P R E S SE 8 i L I N S T R U M E N T SEC D C O R P .E I D E T I C D E S I G N S E L E C T R O N I C T O O L CO. E R U D I T I O M N I U M E X T E N S Y S C ORP .G A L A X Y S Y S T E M S G I MI X , INC.G O D B O U T E L E C T R O N I C S H A L C O M M U N I C A T I O N S C O R P .H A Y D E N B O O K C O M P A N Y , INC. H E U R I S T I C S , INC.I ASI S INC.IBEX

IC M A S T E R & U P D A T E ICOM I M S A II N T E G R A N D R E S E A R C H C O R P . I N T E R F A C E A GE M A G A Z I N E I N T E R S I L , INC.I T TY B I TT Y C O M P U T E R S J E N S E N T O O L S & A L L O Y S K I L O B A U D M A G A Z I N E L O G I C D E S I G N , I N C O R P O R A T E D M E C AM I C R O D E S I G N S M I C R O - T E R M INC.M I C R O C O M P U T E R A S S O C I A T E S

M I C R O P O L I S C O RP .M I C R O T E C H C O M P U T E R CO. M I C R O T R O N I C S M I C R O M A T I O N , INC.M I D W E S T S C I E N T I F I C I NS T R . M I N I - M I C R O S Y S T E M S M A G A Z I N E M I N I T E R M ASSOC.M I N N E S O T A M I N I N G & M F G . CO. N A T I O N A L S E M I C O N D U C T O R N E W M A N C O M P U T E R E X C H A N G E N O R T H S T A R C O M P U T E R S , INC. N O V A L , INC.O H I O S C I E N T I F I C I N S T R U M E N T S O K M A C H I N E S T O O L C O R P .O L I V E R A U D I O E N G I N E E R I N G P A C I F I C O F F I C E S Y S T E M S P A I A E L E C T R O N I C S , INC.P A R A S I T I C E N G I N E E R I N G P E N I N S U L A M A R K E T I N G S E R V I C E S P E O P L E ' S C O M P U T E R CO. P E R I P H E R A L VI S I ON PE R S C IP E R S O N A L C O M P U T I N G M A G A Z I N E P F E I F F E R , E & L P O L Y M O R P H I C S Y S T E M S P R O C E S S O R T E C H N O L O G Y P R O F . & T E C H . C O N S U L T A N T S ASSN. R E A L I S T I C C O N T R O L S C O RP .R I G E L F O U R R O - C H E S Y S T E M S R O M M A G A Z I N E S. D. S A L E SS C I E N T I F I C R E S E A R C H I N S T R U M E N T S M O K E S I G N A L B R O A D C A S T I N G S O L I D S T A T E MUS I C S O U T H E R N C A L I F . COMP. S O C I E T Y S O U T H W E S T T E C H N I C A L P R O D U C T S S U N R I S E E L E C T R O N I C S S U N S E T T E C H N O L O G I E S S Y N E T I C D E S I G N S S Z E R L I P E N T E R P R I S E S T A R B E L L E L E C T R O N I C S T E C H N I C A L D ES I G N L AB S INC. T E C H N I C A L S Y S T E M S C O N S U L T A N T S T E L E T Y P E C O R P O R A T I O N T R I P L E l / P H I D E C K , E C O N O M Y CO. V E C T O R G R A P H I C , INC.V I D E O T E R M I N A L T E C H N O L O G Y W E S T E R N D A T A S Y S T E M S W I Z A R D E N G I N E E R I N G X I M E D I A C O RP .X Y B E KB E L L & H O W E L L S C H O O L S B Y T E S H O P S O F A R I Z O N A C O M P O N E N T S A L E S , INC. C O M P U C O L O R C O RP .D I G I T A L P R O J E C T S , INC. M I C R O - C O M P U T E R D E V I C E S M O V O N I C S

Would you like to exhibit at The First West Coast Com puter Faire or get the Silicon Gulch Gazette with news about the Faire? Write to : The Com puter Faire, Box 1579, Palo A lto, CA 94302. Ask for the Silicon Gulch Gazette, i t ’s free. Ask for exhibitors’ inform ation too if you plan to ren t exhibit space.

Potential exhibitors may telephone (415) 851-7664 fo r current status o f available space. □

HCCMEMBER ORGANIZES^ CONFERENCE SESSION HI

Dick Sherman, K6EIH, has organized a conference session for The First West Coast Com puter Faire on the Application of Microprocessors to Am ateur Radio. Plans for this session include the following topics and speakers:

The Amateur and Microprocessors,Wayne Green, W ZN SD /1, Publisher o f 73 and Kilobaud.

C W M an’s Utopia — Automatic Reception and TransmissionIvar Sanders, W6JDA, Ray Boaz,Verne (Andy) Anderson, W6LPM. (A hardware dem onstration will fo llow the algorithm description.)

Ham R T T Y —Its Evolution and Future,Bob Brehm, WB6QFA, w ith a dem onstra tionof a microprocessor con­trolled R T T Y station by David Altekruse, W6RAW.

Microprocessor Control o f a VHF Repeater,-Lou D onen WB6TXD (A discussion o f control pholosophy and a demonstra­tion using WR6AIÎM.)

Software Generated SST VClay Abrams, K6AF.P (A real scoop!The first all-software generation o f video and sync fo r slow scan television in the know n world!) □

fHOW TO GET INFORM ATIO N A B O U T THE F IR S THj aggig WEST COASTCOMPUTER F A 1 R E ^ M = Z

four HCC Newsletter/Vol 2, Issue 15/March 16, 1977

The Com puter Hobbyist Products’ Floppy Disk Controller Board is designed for use with the S100 Bus and an 8080 or Z-80 type processor, however, the board can be m odified to operate with most CPUs. The board will control up to eight drives in a daisy chain arrangement where only one drive is selected at any given time.

The CUP controller Board does not use DMA for data transfer—it uses the in ter­rupt capability o f the 8080 type processors for efficient software data transfer. All necessary interrupt vectoring circuitry is in­cluded on the board, w ith selectable vectoring.

The board is constructed o f high grade epoxy glass with gold-plated connectors and plated-through holes. The mating con­nector for the drive cable is included. All I.C.s are socketed, except for the voltage regulators. All supplies are regulated on the board —no Zener diodes.

The CHP Floppy Disk Controller uses the Western Digital FD1771 LSI controller. Com plete disk handling for interface to FDOS such as CP/M (copyright 1976,’77, Digital Research, Inc.) can easily be ac­complished in less than 256 Bytes o f ROM.

The hardware is fully buffered from the S100 interface and the connections to the disk drives. Externally adjustable delays are incorporated to accom odate head load de­lays in the various brands of drives. Access rate (track to track) is controlled by the software imbedded in the access commands. In terrupt vectoring for end of operation in terrupt from the FD1771 chip is jum per selectable. Data request interrupts force an enable in terrupt instruction to be executed.

Drive selection is accomplished by a normal 8-bit ou tpu t port, with one line being assigned to each drive. In the un­likely event fh a t more than eight drives might be required, external decoding cir­cuitry could be added, expanding the con­tro ller’s capability to 256 drives!

Com puter Hobbyist Products, Inc. is making this controller available in two forms; kit or fully assembled, tested and burned in. The Controller only costs $300 for one kit, or $375 for the same thing but assembled and tested. Prices for quantities of 50 are $275 each, or $350 each for the assembled and tested lots. The CHP con­troller kit with one REMEX 1000B Drive costs $850 for one or $800 each for quan­tities of 25 or more. Add $75 to the last two prices for assembled and tested con­troller with one REMEX 1000B Drive. CHP, Inc., can be contacted at Post Office Box 18113, San Jose, CA„ 95158 □

Have you ever wondered about the pro­per definition of baud, LISP, o r zero page addressing? The terms are easily found in the MICROCOMPUTER DICTIONARY AND GUIDE. The authors have assembled over 5000 entries in a clear and easy to read and use book. Extensive cross-referen­cing has been used as an aid in locating term s which one might look for in more than one place.

Newcomers and oldtimers alike can benefit from this book. Its a ready re­ference with definitions tha t are up to date. Newcomers should find extensive use for

CALCULATOR LIB is a newsletter dedicated to bring to the calculator en thu­siast up-to-date inform ation on m atters related to calculators. Helping on m atters related to “ calculator w izardry” of its liberated readers, it acts as a clearing house of collective ideas, limited solely by inge­nuity of the human mind.

30 years ago a multi-million dollar m onster was built; it consumed 30 kw power for its 18000 vacuum tubes and had no more calculating power than a $400 programmable calculator has today.

Seven years ago, electrom echanical cal­culators sold for $1000—$2000, with barely as much calculating power as the

Many people interested in com puters and com munications wonder where a good com m unications link is th a t can provide an inform ation interchange between com­puters hobbyists and well as those just in­terested in communicating.

The answer is the growing use of the am ateur radio teletype repeater WR6ACR. This repeater is utilized for the prom otion of radio teletype as a means of cummuni- cations for anyone who is interested. And lately the interest has been computers!

The repeater is located on San Pedro Ridge just north of San Rafael. The fre­quency is 147.93/147.33 Mhz. Those wishing to use the repeater should use narrow band FM transmission with a two- tone audio keying shift of 185 Hz. (2125- 2290). Since the signal is FM, signals from miles around will get through perfect copy almost all the time.

A simple T.U. (term inal unit) tha t de-

the book as they learn about microcom­puter systems and equipm ent.

In addition to the definitions of m icro­electronic term s which fill 516 pages ap­proxim ately 150 pages are devoted to appendices. In the appendices can be found symbols, units and constants of electronics, m athem atics, definitions, acro­nyms, com puter language summaries (APL, BASIC and FORTRAN) numbering systems, and much more.

The M icrocom puter Dictionary and Guide is available at most com puter stores or directly from the publisher. □

under-$20 electronic calculators have today. Industry did no t stop; more and more calculators are being developed for less and less m oney. Today, the calculator has arrived —it is of the people and for the people. These people, liberated by the cal­culator, need regular, continuous and tim ely inform ation.

Editors are Gene J. Hegedus and John DeReyes. The newsletter is published bi-m onthly with a subscription rate of 12 issues for $15. For inform ation contact: TECHNICAL DEVELOPMENTS Post Office Box 2151 Oxnard, CA 93034 □

codes the two tones and keys the printer loop supply is available at low cost. The unit consists of a phase lock loop tone de­coder, a function generator to create the two tones when keyed and associated cir­cuitry for autostart.

Printers are readily available and very low cost. A Teletype Model 15 or 19 is available for less than $100 and can be used with your com puter providing a con­version program is used to convert from ASCII to the Baudot code which is used exclusively on am ateur radio.

Should you w ant more inform ation call; Alan Bowker at (415) 453-1853, San Rafael, or i f yo u live in the Peninsula call Terry Conhoy at (415) 364-3107, Red­wood City. In addition, a dem onstration system will be operating at The First West Coast Com puter Faire, according to Alan Bowker. Users of the repeater will be avail­able to answer questions. □

R T T Y REPEATER I.IXKS AMA TEUR IRADIO A N D COMPUTER HOUR VIST ...

CALCULATOR LIB NEWSLETTER

HCC Newsletter/ Vol 2, Issue 15/March 16, 1977 five

DIABLO PROFESSIONAL USERS GROUP

Diablo Professional users group has been m eeting a t D iablo Valley College on the 4 th W ednesday of each m onth since November.

T he w ord “ professional” refers to tw o categories. One, the novice in com puters — w ho’s an expert in som e o ther field where he makes his living. Tw o, th e expert in com puters —w ho can provide the answers to the first.

F o r you budding technical types, here’s you r chance to get in on the ground floor o f m icrocom puter consulting; the novices y o u ’ll m eet represent a gam ut o f various industries and professions. They are looking fo r those w ith practical know how . A nd in case you d o n ’t recognize yourself, y o u ’re in the consu ltan t category even if y o u ’re a high school or college studen t — b u t have been involved in the hardw are

and /o r softw are JtP scene fo r several years.O ur March m eeting will feature a dis­

cussion o f video display technology and a com parison o f the various com m ercial p ro ­ducts available in th e small system s m arket.

U N D ERG R O U N D B U YIN G GUIDE TELLS ELECTRONIC HOBBYISTS WHERE TO G E T IT

Saratoga, CA. — A new d irectory has ju s t been published th a t helps am ateurs, CBers, experim enters and com puter hobbyists locate equipm ent, parts, supplies and services.

Over 600 sources o f standard and hard-to-find gear are listed in the handy guide. Many of the 600 sources are mail order firms and discounters. All are firms th a t do business w ith electronic hobbyists.

The first section o f the book lists the firms alphabetically, their com plete mailing addresses and phone num bers. A list o f the p ro ­ducts o r services offered is provided along w ith key p roduc t infor­m ation, m inim um order am ounts, shipping charges, etc.

Y ou’ll find everything from million dollar mail order firms w ith m any p roduct lines to week-end garage operations offering a low- cost accessory for a m icrocom puter or CB transceiver. T he second section o f the book is a breakdow n o f pruducts and sources in over 200 categories. U nder each category is a listing o f all firm s th a t sell or m anufacture the item s cross referenced to the first section. For instance, there are over 25 sources o f low voltage (12.6 VDC to 13.8 VDC) pow er supplies and over 50 sources o f digital ICs.

The buying guide contains m any prices and sufficient detail th a t you can m ake you r purchase decisions directly from the book or obtain additional inform ation to m ake you r choice. Catalog prices, if any, are listed.

The last section o f the book includes sources by sta te so you can buy from the firm nearest you when there are several choices. Y ou’ll find local firm s th a t you d idn’t know existed.

The guide easily pays fo r itself by the savings you m ake in buying from the least expensive source. In addition , y o u ’ll save countless hours o f shopping and hunting for hard-to-find item s. Y ou w on’t have to w orry abou t making a poor buying decision —you can easily review all products from the convenience o f you r living room chair.

The UNDERGROUND BUYING GUIDE is available d irect mail from PMS Publishing, 12625 Lido Way, Saratoga, CA 95070. The price is $5.95 plus .55 postage and handling. Californians add .39 sales tax . M oneyback guarantee w ithin 10 days if n o t com pletely satisfied. F or fu rth er inform ation con tac t Dennis A. King, PMS Publishing, 12625 Lido Way, Saratoga, CA 95070; (408)996-0471.

Meetings are held in the College library large conference room from 8 — 10 pm, on the 4 th W ednesday of each m onth . (March 23rd , A pril 27 th , May 25 th , etc.) DVC is near the Willow Pass ex it o f Freew ay 680. For details w rite or call: Bob H endrickson, Electronics D ept, DVC, Pleasant Hill, CA, 94523; (415) 68 7-83 73.

LOW COST MICROCOMPUTER USES U LTR A -F A ST Z-80 pP

C rom em co has announced availability o f a new m icrocom puter designed for de­dicated applications. The low-cost Z-2 m icrocom puter features high speed and state-of-the-art pow er. A high-speed 4 MHz version o f the Z-80 m icroprocessor, generally considered the standard fo r the nex t m icroprocessor generation, gives the Z-2 m ore pow er and greater speed than o ther m icroprocessors.

T he Z-2 contains the fast (250 ns cycle tim e), pow erful CPU card, a m otherboard w ith 21 card sockets and a 30 A heavy du ty pow er supply capable o f m eeting v irtually all pow er needs including floppy disk drives. The circuitry is enclosed by a m etal cabinet designed fo r either rack or bench m ounting. The Z-2 is supported by high-speed (4 MHz) dynam ic RAM mem ories. Substantial softw are includes a m onito r, assembler and a con tro l—BASIC in terp re ter specifically designed fo r m icro­processor con tro l applications. K it price is $539; delivery is from stock to 30 days. For more inform ation con tac t Joe McCrate, Crom em co, Inc., 2432 Charleston Rd., M ountain View, CA 94043 (415)964-7400 .

BITS OF INTEREST

AS A TOOL FO R THE ARTIST

The com puter is a versatile to o l fo r th e m usician, w riter, graphic artist, conceptual artist and the dram atic artist. A class w ith simple program s, special purpose languages, games, graphics, dialogues and o ther en te r­tainm ents in troduces the su tden t to the com puter applied to th e needs o f the artist.

Even if you are a com puter professional or personal com puting addict, com e any­way .Class held a t DeAnza College, A rt 11, W ednesday 2 :30 — 4 :30 pm. Spring Q uarter. In structo r —Gregory Y ob, 326- 4039 (w ork), o r 446-6182 (hom e).

NETWORK

I am studying the possibility o f setting up a hobbyist com puter netw ork w ith be­tw een 3 and 200 hobbyist com puters spread over California (the USA?, the w orld?) com m unicating to each o ther in a message sw itched m ode. Prelim inary re­search indicates this scheme is practical for the transfer o f m odest-sized messages or

files betw een any tw o com puters in the netw ork. A nyone in terested in learning m ore, participating, helping, e tc . please w rite o r call Dave Caulkins, 437 M undel Way, Los A ltos, CA 94022; (4 1 5 )3 2 8 4 2 1 1 days, (415)948-5753 eves.

NEW LIFE FO R OLD ALTA1R

F or over tw o years, San Jose Speedway has been the test bed fo r a com puterized race scoring system . Scientific C om puteri­zation of Racing E quipm ent has an A ltair­operated scoring system and display sign up and running. The sign is 62 fee t long by 8 feet high w ith a g iant moving serial display similar to the little Burroughs P a n a p l e x T M , \ m odified MITS CT256 term inal w rites advertising on audio tape and then reads from the tape to the sign. The term inal keyboard provides instant display o f track inform ation and an­nouncem ents. -Dave Corbin

six HCC Newsletter/Vol 2, Issue 15/March 16, 1977

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IBM 731 S E LE C TR IC I/O T E R M I­N A L — This te rm in a l has never been used excep t fo r occasional m anual typ in g . E qu ipped w ith sp rocke t feed p la tten . Takes all IBM S e lec tric ty p e ­w r ite r fo n ts . P rin ts upper and low er case. W ill trade fo r q u a lity v ideo te r ­m ina l o r $625 cash. Joel M ille r (4 i5 ) 962 -3372 days o r (408) 353 -2663 evenings.

For Sale—W A N G C O M P U TE RS Y S T E M - 2 2 0 0 A w ith cassette, C R T , keyboard , 12K usable R A M , fu ll B A SIC in firm w a re . $ 4 ,50 0 (an $ 8 ,00 0 value). A l Leung 364 -6746 , Box 5272, R edw ood C ity , C A 94063 .

IB E X 16K PROM Board k its are s till o n ly $85 . S-100 co m p a tib le . Uses 2708s, even T .I.s new % price ones ($3 2 .5 0 ). IB E X 1010 Morse, S u ite 5, S unnyva le , C A 94086 .

Group Buy— I 'm se tting up a group b u y on used T T Y s. A p p ro x im a te ly $ 2 5 0 ea. John S w artz (408) 739 -3770 .

I am forming a group— to gather in p u t fo r crea ting a new bus s truc tu re . I need y o u r ideas as to w h a t you w o u ld like to see (o r hate to see) in a new, log ica lly and te ch n ica lly th o u g h t o u t standard bus. C on ta c t John S ch w a rtz / IB E X , 660 San M igue l, S unnyva le , C A 9 4 0 86 . (408) 739-3770 .

Isolation Transformers —5 kW ra ting p rim a ry has seven taps fro m 95 to 2 4 0 V . E le c tro s ta tica lly sh ielded secon­d a ry 1 17V 5 0 /6 0 Hz at 40 amps. S h ipp ing w e igh t app rox . 100 lbs. N ew —$95 . each. Dennis T rim b le (408) 224 -0606 evenings.

There once was a c o m p u te r sc ien tis t w h o fed his m achine w ith all the know ledge o f man and then asked the ques tion , "D oes God e x is t? " T o w h ich the co m p u te r rep lied , "T h e re is one n o w ." David L. Am brose

What's a Com puter?— (A nd W hat Can I Do W ith It? ) —A class fo r

fa m ily and fr iends o f co m p u te r people w h o always w anted to kn o w a bou t com pute rs b u t d id n 't w a n t to ask them . Learn how com pu te rs w o rk , f in d o u t w h a t ja rgon means, p lay some game and s ta rt p rogram m ing. There w ill be fo u r sessions w h ich inc lude a lec tu re , discussion and tim e and the te rm ina ls . Held on Tuesday fro m 7 to 9 pm beg inning A p r il 5. Cost is $25. A C M m em bers' fam ilies get a $5 d iscoun t. E n ro llm e n t is lim ite d to 15. C o m m u n ity C o m pu te r C enter, 1919 M ena lto Ave., M en lo Park, C A 9 4025 (415) 326 -4444 .

Terrence Gregory, President o f N ousou, Inc. will discuss m icrokit system s a t the March 30th meeting.

IBM S E LE C TR IC I /O —This is a brand new IBM se lectric I/O te rm in a l. O rig in a lly $1600 , I am o n ly asking $ 8 0 0 fo r th is b e a u tifu l te rm in a l w ith sp rocke t feed p la tten . A lso fo r sale — one M o to ro la 6 800 p ro to board fu l ly assembled and w o rk in g , $175. Call evenings, R ick P a r f it t (415) 564-1332 .

For Sale—G A TES A C O U S T IN E T -Sound p ro o f cover fo r any T e le type m odels 32, 33 w ith paper punch. Tab le to p m o d e l—c o m p le te /p e rfe c t c o n d it io n . $100. Call T om (415) 388- 9 220 o r w r ite B ox 383 , M ill V a lle y , C A 94941 .

S U N T R O N IX graphics driver —fa c to ry assembled and tested, lis t a t $130 , sell fo r $ 100 ; M N H -A E 1900 Baud M O D E M , lis t $ 1 0 00 , sell fo r $35 w ith d o cu m e n ta tio n , yo u pay sh ipp ing (20 lbs.) W m . J. Schenker, M .D ., 2086 Essenay Ave., W a lnu t Creek, C A (415) 939 -6295 .

W anted— ' A " tape cartridges fo r A m p e x CDR1 data recorder. Dean B ennett, 517 H illb r ig h t Place, San Jose, C A 95123 .

Club L ib rary— G ordon French, c lub lib ra ria n , has lo ts o f in te res ting m a­te ria l and is able to loan i t to anyone w ith a d e fin ite need, b u t . .. please ad­here to the fo llo w in g :

L im it y o u r te lephone calls to the hours o f 7 pm to 9 pm weekdays o n ly . Th is is im p o rta n t. G o rdon 's phone num ber is (415) 3 2 5 -4209 in M enlo Park. Be spec ific w ith y o u r request and G ordon can p ro b a b ly help y o u — he ca n n o t ran d o m ly review the con ten ts o f the lib ra ry fo r you .

No rep ro d u c tion s w ill be made o f any m ateria ls.

A ll m ateria ls loaned m ust be re­tu rn e d so th e y are available fo r others to use in the fu tu re .

HOW TO G E T T H E N E W S L E T T E R -A n yo n e in terested in com pute rs as a h obby m ay receive the N E W S LE T TE R by sending a request to the Homebrew Computer Club Newsletter, P.O. Box 626 , M ou n ta in V ie w , C A 94 0 42 . The N E W S LE T TE R is d is tr ib u te d m o n th ly a t the c lub m eetings and is also m ailed to ind iv idua ls w h o are unable to a t­tend the meetings.

I f you have an in p u t to the NEW S­L E T T E R , send i t in and i t w il l be p u b ­lished as q u ic k ly as possible. However, the ed ito rs canno t p rom ise th a t every­th in g sent w il l be pub lished. A ll m anu­scrip ts m ust be typ e d and ca re fu lly p ro o fe d . A ll lis tings and diagrams should be as c lear and easy to read as possible.

The N E W S LE T TE R is made pos­sible by y o u r donations. Please re­m em ber th a t we m ust pay fo r postage, labels and p r in tin g . D ona tions m ay be given to Ray Boaz at the c lu b m eetings o r sent to the above address.

%

H C C N ew sle tte r/V o l 2, Issue 15/M arch 16, 1977 seven

contentsCMOS Cookbook/Book Review-----------------------Com puter Music Interest Group Forming---------Santa Cruz Club Grows Up by Joel M iller---------Reduced Admission for HCC Membera at Faire.Survey Tabulating Program by Ed H ughot--------Faire’s Exibitors List Growing F ast___________How To G et Inform ation A bout The First West Coast Com puter Faire.HCC Member Organizes Conference Session­s ' - 100 Full Size Floppy Disk C ontroller___Micro Com puter Dictionary And Guideby Charles J. Sipple and David A . K idd_____Calculator Lib N ew sletter_________________RTTY Repeater Links A m ateur RadioAnd Com puter H obbyist_____________News Release------------------------------------

-1.1. 1.1-2.4

.4

.4-5

.5

.5

.5

.6Diablo Professional Users GroupLow Cost M icrocom puter Uses Ultra Fast Z-80 pPUnderground Buying Guide Tells ElectronicH obbyists Where To Get ItThe Com puter A s A Tool For The A rtis tH obbyist Com puter Network?New Life For Old Altair

!

; (408) 353-3609 LAUREL PUBLICATIONS (408) 353-3609.

■ < f ) l

D raftin g I l lu s tra tio n s C o m p o s it io n L a y -o u t P h o to g ra p h y A d v ertisin g i

: TYPESETTING f ;■ UJ B o o k s M agazine A rtic le s T e c h n ic a l M anuals P e rio d ica ls N ew sle tte rs ¿ j .

Í(408) 353-3609 LAUREL PUBLICATIONS (408) 353-3609

The Homebrew Com puter Club meets at 7 pm at the Stanford Linear Accelerator Center A uditorium . Dates scheduled for March are the 2nd, 16th and 30th, for April are the 15th and 29th , and May the 13th and 25th. The dates and location are subject to change. If a change does occur, every effort will be made to provide advance notice in the NEWSLETTER.

Q a u d i to r iu m

FREEWAY (280 )

HOMEBREW COMPUTER CLUB NEWSLETTER

P.O. Box 626 Mountain View, CA 94042

FIRST CLASS MAIL

eight HCC Newsletter/Vol 2, Issue 15/March 16, 1977

surveyhcc

homebrew computer club

A t the meeting January 19, 1977This survey was taken during the

Homebrew Com puter Club regular m eet­ing on January 19, 1977. A pproxim ately 240 people attended the meeting. The survey shows a remarkable num ber of personal com puters in use by the club with m any systems running w ith 8K bytes or more o f m em ory. Seventy-five percent of this group own com puter systems. Pro­jecting this percentage of com puters in operation to the 1500 people th a t receive the Homebrew Com puter Club NEWS­LETTER would indicate 1125 com puters owned by the group. There is plenty of room for error in this type of projecting but it is a very good indication of the investment of club members in personal com puter products. □

random databy robert reiling

Personal and home computing continue to interest more and more people. The hobbyist clubs are expanding, more com­puter stores are opening, new products are being announced, magazines devoted to personai computers are increasing in number, and predictions are being made about where we are going. A few people are attem pting to determine what has hap­pened in the past two years and how many computers and com puter people are out there.

¿yp ¿y $ a * <?£ #5

Q.'--S'

hcc meetingsHomebrew Computer Club Meeting

Schedule For Remainder of 1977March 16 and 30April 15 and 29May 13 and 25June 8 and 22July 6 and 20August 3 , 1 7 and 31Septem ber 14 and 28October 12 and 26November 9 and 23December 7 and 21

All dates are subject to change or can­cellation. If a change does occur, advance notice will be published in the NEWS­LETTER if time permits. □

CLUB L IB R A R Y — Gordon French, club librarian, has lots o f interesting material and is able to loan it to any­one with a definite need, bu t . . . please adhere to the following:

tit Limit your telephone calls to the hours of 7PM to 9PM weekdays only. This is im portant. G ordon’s phone num ber is (415) 325-4209 in Menlo Park.

t-t Be specific with your request and Gordon can probably help y o u -h e cannot random ly review the contents of the library for you.

* N o reproductions will be made of any materials.

*A11 materials loaned must be re­turned so they are available for others to use in the future.

**** RETURN THIS FORM ****C o n f i r m a t i o n o f y o u r c o n t i n u i n g i n t e r e s t i n t h e h o m e b r e w

COMPUTER CLUB NEWSLETTER i s NEEDED, PLEASE COMPLETE THIS FORM,,

& RETURN IT WITH YOUR DONATION. MAKE CHECKS PAYABLE TO

" H omebrew Co m p u t e r Cl u b , "

Ma i l t h i s form a n d your d o n a t i o n t o : Homebrew Co m p u t e r Cl u bBox 626 H t V i e w CA 94042

P l e a s e c o n s i d e r t h a t t h e m in imum c o s t o f p r o v i d i n g t h e n e w s l e t t e rTO YOU IS $6 PER YEAR. THIS COVERS THE BARE BONES EXPENSES, & DOES NOT ALLOW FOR USE OF ANY PHOTOS, A $10 DONATION WILL PROVIDE SOME F L E X I B I L I T Y IN THE BUDGET, & EASE THE NEWSLETTER STAFF 'S BURDEN, A SLIGHTLY LARGER DONATION WOULD REALLY BE APPRECIATED, SAY $12, & THEN MAYBE WE COULD THINK ABOUT ADDITIONAL CLUB SERVICES.

( ) Ye s , k e e p my name on t h e m a i l i n g l i s t . My d o n a t i o nOF $___ IS ENCLOSED,

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PRINT CLEARLY, OR AFFIX YOUR MAILING LABEL.

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( ) D u r i n g 1977 I e x p e c t t o p u r c h a s e p e r s o n a l c o m p u t e r e q u i p m e n t

AS FOLLOWS: ______________________________________________________________

What do y o u t h i n k o f t h e n e w s l e t t e r ?

W ou ld y o u l i k e t o be e d i t o r o f a c o l u m n ? ( ) Y e s , ( ) No S u b j e c t _____________________________________________________________