Apple Silentype
| Apple Silentype | |
|---|---|
 |
|
| Apple Silentype thermal printer (photo: Christian Brockmann) | |
| Manufacturer | Trendcom, for Apple Computer, Inc. |
| Type | Thermal printer |
| Release date | June 1979 |
| Interface | Silentype interface card in an Apple II slot (slot 1 recommended) |
| Compatible | Apple II and Apple II Plus with at least 16K; Apple III |
| Model | A2M0032 (non-EMI), A2M0036 (EMI) |
| Power | From the Apple II through the interface card |
The Apple Silentype is a thermal printer for the Apple II that Apple released in June 1979, its first printer. It was built for Apple by Trendcom of Sunnyvale, California, and Wikipedia describes it as a rebadged Trendcom 200.[1][2] It prints upper- and lower-case text at up to 40 characters per second and Apple II high-resolution graphics on a roll of heat-sensitive paper, with a seven-dot print head. The printer has no power supply of its own: it plugs into an interface card in the Apple II and takes its power from the computer.[3][4]
Specifications
[edit | edit source]| Item | Value |
|---|---|
| Printing method | Thermal, on heat-sensitive paper roll |
| Print head | Seven dots, ceramic |
| Speed | Up to 40 characters per second |
| Text | Upper and lower case; left margin 0-82 and right margin 1-83 columns |
| Graphics | Apple II high-resolution pages 1 and 2, normal or inverse |
| Direction | Bidirectional or unidirectional (software setting) |
| Intensity | Eight levels, 0 to 7 (default 5) |
| Host | Apple II or II Plus with 16K or more, Integer BASIC, Applesoft, Pascal or the Monitor |
| Power | Drawn from the Apple II through the interface card |
Interface card
[edit | edit source]The Silentype interface card holds the printer's control ROM (Apple part 342-0039), a 256 × 4 static RAM buffer (2112A-4) and 74LS-series logic.[5] Apple's manual recommends slot 1. The card has a C800 ROM, and another card with a C800 ROM, such as a Serial card or a Graphics Tablet card, can confuse the Apple into sending output to the wrong card. According to the manual this can only happen when the other card is in the slot numbered one below the printer card; fit the printer card in slot 1, or put any other C800 card in a higher-numbered slot. For the Pascal procedures in the manual, the Silentype card must be the only C800 card fitted.[3]
Inside the printer, a deserializer card on the left of the chassis connects the interface cable (J3), the two motors, the print head cable and the left margin switch.[6]
EMI and non-EMI versions
[edit | edit source]Like the Apple II, the Silentype was modified to reduce the radio-frequency interference of the early models. Apple's procedures give two chassis and two deserializer cards:[7]
| Non-EMI | EMI | |
|---|---|---|
| Model number on the rear label | A2M0032 | A2M0036 |
| Left margin switch | One wire | Two wires |
| Deserializer card (number on the trace side) | 820-0020-01, single pin J5 for the margin switch | 820-0020-02, extra pin J6 |
Apple supplied only EMI parts for service. An EMI deserializer card fitted to a non-EMI chassis prints with an uneven left margin unless it is modified with a jumper; the procedure is on Apple Silentype General Maintenance#Fitting an EMI card to a non-EMI printer.[7]
The Silentype in the photograph on Wikimedia Commons carries model number A3M0001 on its label.[2] Wikipedia states that the Silentype also worked with the Apple III.[1]
Maintenance and troubleshooting
[edit | edit source]- Apple Silentype General Maintenance: paper, the drive string and belt, alignment and the EMI card modification.
- Apple Silentype Troubleshooting Guide: the ERR message, Apple's diagnostic tests and its troubleshooting chart.
Documentation
[edit | edit source]- Apple Silentype Documentation: Apple's Silentype Printer Operation and Reference Manual (1980) and Silentype Printer Technical Procedures.
Related pages
[edit | edit source]- Apple II, Apple II Plus
- Apple Scribe Printer, Apple's later thermal transfer printer
References
[edit | edit source]- ↑ 1.0 1.1 Wikipedia, "List of Apple printers", section Early products, https://en.wikipedia.org/wiki/List_of_Apple_printers (retrieved 2026-10-02). Source for: the Silentype as Apple's first printer, released in June 1979; a thermal printer using special paper; compatibility with the Apple III; a rebranded Trendcom 200.
- ↑ 2.0 2.1 Photograph of a Silentype's rear label, hosted as File:Apple Silentype rear label.jpg (Christian Brockmann, Wikimedia Commons). The label reads "Silentype printer, manufactured exclusively for Apple Computer Inc. by Trendcom, Sunnyvale, California", with model number A3M0001, and warns to connect the cable only to the specified Apple Silentype interface.
- ↑ 3.0 3.1 3.2 Apple Computer, Inc., Silentype Printer Operation and Reference Manual, product number 030-0095-00 (1980), hosted as File:Apple Silentype Operation and Reference Manual 030-0095-00 1980.pdf. Printed page + 5 = PDF page. Source for: up to 40 characters per second, upper and lower case, text and high-resolution graphics (Introduction, p. 1); any Apple II or II Plus with at least 16K, power taken from the Apple's supply, and the contents of the box (p. 3); checking the paper roll and its bearings (pp. 3-4); installing the interface card, slot 1, and the C800 ROM conflict with other cards (pp. 4-8, and p. 20 for Pascal); replacing the paper, the pink end-of-roll stripe, storing paper and printouts, and the ERR message (Appendix A, pp. 43-44); the parameter table (Appendix B, p. 45).
- ↑ 4.0 4.1 Apple Computer, Inc., Silentype Printer Technical Procedures, Diagnostics, pp. 3.3-3.5 (PDF pp. 16-18), hosted as File:Apple Silentype Technical Procedures.pdf. Source for: the print head dot test printing one line for each of the seven dots on the print head; the eight-level print intensity test; the bidirectional registration test and its tolerance of one dot.
- ↑ Silentype Printer Technical Procedures, Illustrated Parts List, pp. 6.1-6.5 (PDF pp. 24-28). Source for: the printer parts (print head 970-0418, Dacron cord 970-0442, head drive belt 970-0443, head cable 970-0401, cord pulley 970-0410, paper bearing assembly 970-0406, platen 970-0402, head motor assembly 970-0404) and the interface card ICs (control ROM 342-0039, RAM 2112A-4 334-2112, 74LS-series logic).
- ↑ Silentype Printer Technical Procedures, Take-Apart, pp. 1.1-1.11 (PDF pp. 2-12). Source for: removing the cover and base (Torx screws; not turning the printer fully over because the paper roll is held in by gravity; the deserializer card and connector J3); replacing the head cable; replacing the brittle ceramic print head; the platen going back square edge up, or the print head shorts out and ruins the Silentype; replacing the Dacron drive string; replacing the deserializer card; the bottom screw forming part of the ground on non-EMI printers; not applying power while the printer assembly is loose in the base.
- ↑ 7.0 7.1 7.2 Silentype Printer Technical Procedures, Modifications, EMI Modifications to the Silentype, pp. 5.1-5.4 (PDF pp. 20-23). Source for: the EMI (RFI) modification; model numbers A2M0032 (non-EMI) and A2M0036 (EMI) on the label on the back of the case; the one-wire and two-wire left margin switch; deserializer cards 820-0020-01 (non-EMI, pin J5) and 820-0020-02 (EMI, extra pin J6); only EMI parts being supplied; an EMI card in a non-EMI chassis printing with an uneven left margin unless modified; the jumper wire between two solder pads; Apple Service Bulletin #39.
