Reference

This volume collects the ET-3200’s specifications, its model and part numbers, the course materials that went with it, every manual and document located, and the related Heath equipment in one place. The rest of the dive explains them: the line and dates in volume 1, the circuit in volume 2, and the courses in volume 4.

7.1 Specifications

As printed in the ET-3200 manual of 1975 and repeated without change in the ET-3200B manual of 1983.

Table 1 — Specifications

Power supplies
Output voltages	+12 V d.c. at 100 mA; −12 V d.c. at 100 mA; +5 V d.c. at 500 mA with thermal overload protection
Load regulation	+12 V and −12 V better than 1 %; +5 V better than 2 %
Data switches
States	+5 V or 0 V
Maximum current	10 mA each switch
Outputs	four terminals, one for each switch
Logic switches
Type	momentary contact, spring-loaded
Circuit	two flip-flop latches for contact-bounce buffering
Output states	complementary, +5 V and +0.2 V
Clock
Frequency selection	three-position slide switch
Output frequency	1 Hz, 1 kHz, 100 kHz, ±20 %
Duty cycle	45 %
Output voltage	5 V peak-to-peak
Output terminals	normal and complement
Logic indicators	red light-emitting diodes
General
Power requirements	105–130 V or 210–260 V r.m.s., 50–60 Hz, 15 W maximum
Fuse	3/16 A slow-blow
Dimensions	12⅛ in wide × 11¾ in deep × 3½ in high
Net weight	4 lb (shipping weight 6 lb in the catalogues)

Additional figures from the manual’s Operation section and the catalogues: line-frequency square-wave output at 60 or 50 Hz, “0.1 % accuracy”; connector blocks accept solid wire up to #20 (0.032 in), four common contacts per block; breadboarding socket with 128 five-point terminal strips in 64 pairs, taking up to eight 14- or 16-pin DIPs and also 24-, 28- and 40-pin DIPs; compatible with DTL, TTL, CMOS, nMOS and pMOS, and with RTL and ECL using simple additions (ET-3200 manual, pp. 34 and 41; ET-3200B manual, p. 46; Christmas 1975 catalogue, p. 65).

Some 1981 and 1982 catalogues print the +12 V rating as “500 mA”. The manuals, the earlier catalogues and the circuit’s 4.7 Ω current limit all give 100 mA, so the catalogue figure is a misprint.

7.2 Model numbers

Table 2 — Model numbers

Number	What it is	Seen
ET-3200	Digital Design Experimenter, kit	Christmas 1975 – Winter 1981
ETW-3200	same, factory assembled and tested	Fall 1977 – Winter 1981; also the classroom “Required Course Trainer”
ET-3200A / ETW-3200A	revised version, kit / assembled	Christmas 1981 – about 1983
ET-3200B / ETW-3200B	revised version, kit / assembled	1983 – at least Fall 1987
EE-3201	Digital Techniques, self-instruction course	Christmas 1975 onward
EEA-3201	optional cassettes for EE-3201 (duplicating the records)	Fall 1977 onward
EES-3201 / EES-3201A	course and trainer ordered together	Fall 1977 / Winter 1981–82
ECC-3201	College-Level Examination for the course	Winter 1981
EE-3201A / EE-3201-A	revised Digital Techniques course	about 1983 onward (text © 1983, 1993, 1998)
EB-6201, -30, -40, -50	classroom student text, parts kit, workbook, instructor’s guide	1978 onward
EB-6201-71, EB-6201-52	laboratory manual and administrator’s guide for the ETB-6201 module (ET-3700)	Fall 1987
EE-3202 / EE-3202A	CMOS Digital Techniques course	Winter 1981–82 / Fall 1985

Heath part numbers of note: circuit board 85-1599-2 (ET-3200) and 85-2572-3 (ET-3200B); power transformer 54-893 (both); manual 595-1740 (ET-3200) and 595-2936 (ET-3200B); EE-3201A text 595-2931; EB-6201-71 lab book 595-3813 (ET-3200 manual; ET-3200B manual).

7.3 Catalogue appearances and prices

Table 3 — Catalogue appearances and prices

Catalogue	Page	ET-3200 kit	Wired	EE-3201
Christmas 1975 (No. 806)	63–65	$69.95	—	$49.95
Spring 1976	87	$69.95	—	$49.95
Fall 1977 (No. 817)	100	$69.95	$99.95	$49.95
Christmas 1977 (No. 818)	101	$79.95	$119.95	$49.95
Spring 1978	103	$84.95	$129.95	$54.95
Winter 1978	—	$84.95	$129.95	$49.95
Fall 1979	70	$84.95	$149.95	$59.95
1980 (No. 848)	—	$84.95	$149.95	$59.95
Winter 1981	39	$89.95	$159.95	$79.95
Winter 1981–82	79	ET-3200A $89.95	$159.95	$79.95
Christmas 1981	39	ET-3200A $89.95	$159.95	$79.95
Christmas 1982	35	ET-3200A $94.95	$169.95	$79.95
Fall 1983	—	ET-3200A named in text; ETW-3200B $179.95 in the classroom price list
Fall 1985	—	ET-3200B $109.95	$179.95	EE-3201A $99.95
Fall 1987	62	ET-3200-B named as alternative to the new ET-3700		EE-3201-A $99.95

A dash in the page column means the page number could not be read from the scan. Prices were taken from the scans’ text layers or OCR and checked against the page images for the pages illustrated in this dive.

7.4 Manuals and documents

Heath assembly manuals are numbered 595-nnnn with a two-digit printing suffix. The table lists every ET-3200-related document located online, with the data the project’s hosting rule needs. No title below is hosted by this site. Every one carries a copyright notice and dates from 1975 or later. Under the project’s rule (host only titles published before 1964 without renewal, or published without a notice before 1 March 1989) none qualifies, so all are link-only. No renewal search was made, because none is needed for works of 1964–1977, whose renewal became automatic under the Copyright Renewal Act of 1992, or for works of 1978 and later, which need no renewal. None of these titles appears on the Tubular Electronics list of Heath manuals withheld as still in copyright, but that list does include the successor ETW-3700 (Tubular Electronics).

Table 4 — Manuals and documents

Title	Part no.	Year	Copyright notice seen	Renewal search	Free scan
Heathkit Manual for the Digital Design Experimenter, Model ET-3200	595-1740-03	1975	yes, “Copyright © 1975 Heath Company” on the title page	not done (not needed; see above)	Internet Archive, heathkitmanuals (52 pages)
ET-3200 Illustration Booklet (Pictorials 2-1, 2-2; schematic)	—	1975–76	yes: schematic © 1975; Pictorial 2-2 © 1976	not done	Internet Archive, heathkitmanuals · schematic-only copy
ET-3200A manual	not located	about 1981	—	—	no scan found
Heathkit Manual for the Digital Design Experimenter, Model ET-3200B	595-2936-06	1983	yes, “Copyright © 1983 Heath Company”	not needed	Internet Archive, DLARC (56 pages)
ET-3200B Illustration Booklet (specifications, circuit description, compatibility, schematic, X-ray view)	—	1983	not legible on the scan examined	not needed	Internet Archive, heathkitmanuals (10 pages)
EE-3201 Digital Techniques (original course)	not located	1975	—	—	no scan found
Digital Techniques, Model EE-3201A, Individual Learning System textbook	595-2931-09	1983; reprinted 1993, 1998	yes, “Copyright © 1998, 1993, 1983 Heathkit Company, Inc.”; ISBN 0-87119-011-7	not needed	Internet Archive (961 pages)
Digital Techniques Lab Book, EB-6201-71 (for ETB-6201 module and ET-3700)	595-3813-06	1987 or later	none seen in the text layer	not needed	Internet Archive
Heathkit Manual for the Microprocessor Trainer, Model ET-3400	595-2021-03	1977	yes, © 1977	not needed	Internet Archive, DLARC
same, later printing	595-2021-06	1977	yes, © 1977	not needed	Internet Archive
ET-3400 manual with EE-3401 Unit 1, Number Systems and Codes	595-2039-02 (Unit 1)	1977	yes, © 1977	not needed	Internet Archive

The ET-3200 manual has not yet been found in the Internet Archive’s DLARC collection, which usually has the cleanest scans. The heathkitmanuals copy is complete and legible. Paper reprints of Heath manuals are sold by Data Professionals, now part of the Heath Company (history dive, volume 7).

7.5 Related Heath equipment

Table 5 — Related Heath equipment

Model	What	Relation
ET-3100 / A / B	Electronic Design Experimenter (analog)	twin trainer, same launch and cabinet size; its own dive
ET-3300 / A	laboratory breadboard	larger breadboard with supplies, 1976 on
ET-3400 / A	Microprocessor Trainer	the next course’s trainer; see volume 5
ET-3700	Digital Trainer	successor, Fall 1987
ET-3567	Trainer Backpack accessory	fits the ET-3600 and ET-3700
ETB-6201 / -A	Digital Techniques experiment module	pre-wired board for the ET-3700 and Backpack
IM-17	utility solid-state voltmeter	the meter named in the 1975 course requirements
IM-5284	multimeter	recommended for the Digital Techniques experiments, 1981–82
IO-4105	single-trace oscilloscope	recommended for the Digital Techniques experiments, 1981–82

Sources: the catalogues cited above; Eckweiler #129 for the ET-3100 series.

Further reading

• Eckweiler, Bob (AF6C), “Heathkit of the Month #129: Heathkit ET-3100/A/B Electronic Design Experimenter/Trainer (and Associated Heath Offered Courses)”. The best published account of the ET-3100 series and the analog course line, and a model for the digital side. https://www.w6ze.org/Heathkit/Heathkit_129_ET3100B.pdf
• Frenzel, Lou, “The History of Personal Computers, Part 2: The Heathkit Story”, Electronic Design, 30 December 2013. First-hand account of the founding of Heath’s education business and the ET-3400. https://www.electronicdesign.com/technologies/communications/article/21799215/the-history-of-personal-computers-part-2-the-heathkit-story
• Heathkit history dive, especially volume 5 (Heath goes digital; the ET-3400), volume 6 (Zenith and Bull) and volume 7 (Heathkit Educational Systems after the kits).
• World Radio History, Heathkit catalogue archive, the source for every date and price in this dive. https://www.worldradiohistory.com/Archive-Catalogs/Heathkit_Catalogs.htm

Sources

• Heath Company. Heathkit Manual for the Digital Design Experimenter, Model ET-3200, 595-1740-03, © 1975. https://archive.org/details/Heathkit_ET-3200_Digital_Design_Experimenter
• Heath Company. ET-3200 Illustration Booklet and schematic. https://archive.org/details/heathkit_et-3200 · https://archive.org/details/HeathkitET3200DigitalDesignExperimenterschematic
• Heath Company. Heathkit Manual for the Digital Design Experimenter, Model ET-3200B, 595-2936-06, © 1983. https://archive.org/details/manualsplus_11835 ; illustration booklet https://archive.org/details/Heathkit_ET-3200B_Experimenter
• Heathkit Company, Inc. Digital Techniques, EE-3201A, 595-2931-09. https://archive.org/details/ee-3201-a-digital-techniques-individual-learning-system-textbook-1998
• Heathkit Educational Systems. Digital Techniques Lab Book, EB-6201-71, 595-3813-06. https://archive.org/details/digital-techniques-lab-book-eb-6201-71
• Heath Company. Heathkit Manual for the Microprocessor Trainer, Model ET-3400. https://archive.org/details/manualsplus_11737 · https://archive.org/details/HeathkitManualForTheEt-3400MicroprocessorTrainer · https://archive.org/details/HeathkitET3400MicroprocessorTrainermanualTraining
• Heathkit catalogues, 1975–1987, and Heathkit/Zenith Educational Systems catalogue 811-29R. World Radio History. https://www.worldradiohistory.com/Archive-Catalogs/Heathkit_Catalogs.htm
• Tubular Electronics. Heathkit manuals and copyright list. https://tubularelectronics.com/?page_id=64
• Eckweiler, Bob (AF6C). “Heathkit of the Month #129.” https://www.w6ze.org/Heathkit/Heathkit_129_ET3100B.pdf