Seikosha Printers

Personal Computer News

Kenn Garroch

PRINTS OF THE REALM Finding the right printer for your computer can be as difficult as winding your way through a maze. But, there's hope on the horizon - simply consult Kenn Garroch's guide to what's what and for how much. Printers range from cheap thermal narrow-paper machines to large expensive daisy wheels. The in between ground is held by the dot matrix, Epson lookalike printers. There are also colour printers which range from the cheapest pen plotters to the ribbon and ink jet machines that produce high quality prints. The bottom end of the printer market is generally held by the thermal printers, and the pen plotters. Thermal printers need either special paper, available from many stationers, or carbon transfer ribbons such as those in the Brother range (EP22/44/HR5). The pen plotters use one of four coloured pens which move horizontally across the paper. The paper moves vertically allowing characters and graphics to be drawn on the paper. They tend to be slow and are generally limited to narrow (4.5in) paper. Dot matrix is the most common type of printer these days. A vertical line of needles presses an inked or carbon ribbon onto the paper. At the bottom of the range the capabilities are limited but usually include bit image graphics and a choice of character sets. At the top end, features such as proportional spacing, near letter quality (NLQ), buffers, and downloadable character sets are available. But you pay for the extra facilities. For the more serious users, the daisy wheel type of printer may be necessary. These use a spoked wheel with a letter on each spoke. The letters are stamped against a ribbon just like a typewriter. The main problems are inflexibility, as you are limited to the characters available on the wheel. They also tend to be slow, roughly 10-20cps, and very noisy, which irritates some people. INTERFACES A snag you may run across is the type of interface that connects the printer to your computer. The most common is the Centronics parallel connection. The other main type is the serial or RS232 interface. This is usually available either as an alternative to Centronics, or as a separate adaptor for more cash (denoted by the £ sign in the list below). When buying a printer, you will probably be spoilt for choice. The first thing is to decide what you need a printer for - letter quality, listings, graphics, colour, etc. Next, decide what you can pay, and see which printers are in your price range. Once you have a selection, think of what you may need the printer for in the future. This should narrow the choice down to one or two. At this point, you should scour the advertisements in the computer press for the company that offers the best deal for the printer you want. Now you have a printer that should last for years without any problems. In case of hitches, make sure the dealer you buy the printer from has some kind of backup and guarantee policy. THERMAL PRINTERS NAME: TC600 PRICE: £577.25 SPEED: 16cps INTERFACES: RS232 PRINT METHOD: Carbon ribbon/thermal PAPER SIZE: 8.5in COMMENTS: Plots graphs, built-in keyboard and RAM, disk drive available. SUPPLIER: Jones Brother [redacted] NAME: HR5 PRICE: £180.85 SPEED: 16cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Carbon ribbon/thermal PAPER SIZE: 8.5in COMMENTS: Battery powered 4xU2s, similar to EP-44 without keyboard. SUPPLIER: Jones Brother [redacted] NAME: EP22 PRICE: £169.95 SPEED: 16cps INTERFACES: RS232 PRINT METHOD: Carbon ribbon/thermal PAPER SIZE: 8.5in COMMENTS: Battery powered 4xU2 SUPPLIER: Jones Brother [redacted] NAME: Epson P-40 PRICE: £109 SPEED: 10cps INTERFACES: Optional Centronics or RS232 PRINT METHOD: Thermal PAPER SIZE: 4.5in COMMENTS: Cheaper but paper is narrow SUPPLIER: Peripheral Hardware [redacted] DOT MATRIX PRINTERS NAME: Smith-Corona D200 PRICE: £483 SPEED: 160cps INTERFACES: RS232 and Centronics PRINT METHOD: Dot matrix PAPER SIZE: 8.5in COMMENTS: Includes NLQ, 2K internal buffer, IBM compatibility. SUPPLIER: Smith Corona dealers NAME: Walters WM-80 PRICE: £228.28 SPEED: 80cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Dot matrix PAPER SIZE: 8.5in COMMENTS: Bog standard Epson lookalike. SUPPLIER: Walters Microsystems [redacted] NAME: Shinwa CPA-80 PRICE: £228.85 (Centronics), £251.85 (RS232) SPEED: 100cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Dot matrix PAPER SIZE: 8.5in COMMENTS: Pretty well Epson compatible SUPPLIER: Micro-Peripherals [redacted] NAME: Cana PW1080A PRICE: £320 SPEED: 160cps draft/75cps NLQ INTERFACES: Centronics/RS232(£) PRINT METHOD: Dot matrix PAPER SIZE: 8.5in COMMENTS: Includes NLQ option. SUPPLIER: CJE Micros [redacted]/Maplin [redacted] NAME: Brothers M1009 PRICE: £199 SPEED: 60cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Dot matrix PAPER SIZE: 8.5in COMMENTS: A compact printer, almost completely Epson control code compatible. SUPPLIER: Jones Brother [redacted] NAME: Riteman Plus PRICE: £260 SPEED: 120cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Dot matrix PAPER SIZE: 8.5in COMMENTS: Tractor fee mech available SUPPLIER: KODE [redacted] NAME: Smith Corona Fastex 80 PRICE: £224.25 SPEED: 80cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Dot matrix PAPER SIZE: 8.5in COMMENTS: Tractor feed available. SUPPLIER: Smith-Corona dealers NAME: OKI Microline 80 PRICE: £229 SPEED: 80cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Dot matrix PAPER SIZE: 9.5in SUPPLIER: X-DATA [redacted] NAME: Epson RX80 F/T PRICE: £328 SPEED: 100cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Dot matrix PAPER SIZE: 8.5in COMMENTS: Taken as standard SUPPLIER: Epson dealers NAME: Mannesman Tally 80 PRICE: £299 SPEED: 80cps INTERFACES: Centronics PRINT METHOD: Dot matrix PAPER SIZE: 8.5in COMMENTS: Mannesman Tally [redacted] NAME: Star Gemini 10X PRICE: £286 SPEED: 120cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Dot matrix PAPER SIZE: 8.5in SUPPLIER: Keyaki [redacted] LETTER QUALITY PRINTERS NAME: IBICO LTR-1 PRICE: £175 SPEED: 12cps INTERFACES: Centronics PRINT METHOD: Letters on cylindrical roller - a bit like a rubber golf ball. PAPER SIZE: 8.5in COMMENTS: Interfaces available for Commodore 64, and Spectrum at £29.95, and £39.95 respectively. SUPPLIER: IBICO [redacted] NAME: Silver Reed EXP500 PRICE: £378 SPEED: 18cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Daisy wheel PAPER SIZE: 10in SUPPLIER: C/WP Computers [redacted] NAME: Juki 6100 PRICE: £385.25 SPEED: 17cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Daisy wheel PAPER SIZE: 13in COMMENTS: Takes Triumph Adler wheels. SUPPLIER: Most printer dealers NAME: Smith Corona L1000 PRICE: £368 SPEED: 12cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Daisy wheel PAPER SIZE: 13in COMMENTS: Replacement for the TP1 SUPPLIER: Smith-Corona dealers NAME: Turbo-20 PRICE: £497 SPEED: 18cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Daisy wheel PAPER SIZE: 15in SUPPLIER: Office Efficiency Machines [redacted] COLOUR PRINTERS NAME: Seikosha GP700-A PRICE: £488 SPEED: 50cps INTERFACES: Centronics PRINT METHOD: 7-colour ribbon dot matrix PAPER SIZE: 8.5in SUPPLIER: DRG Business Machines [redacted] NAME: Integrex Colour Jet PRICE: £654.35 SPEED: 40cps INTERFACES: Centronics/RS232(£) PRINT METHOD: Dot matrix ink jet PAPER SIZE: 8.5in COMMENTS: No tractor feed available; interface for viewdata system. SUPPLIER: Integrex [redacted] NAME: CGP 1154 PRICE: £149 SPEED: 12cps INTERFACES: Centronics PRINT METHOD: Pen plotter PAPER SIZE: 4.5in COMMENTS: One of many 4-colour pen plotters, all the same design and roughly the same price. SUPPLIER: Tandy shops NAME: Tandy CGP-220 PRICE: £499 SPEED: 37cps INTERFACES: Centronics PRINT METHOD: 7-colour ink jet PAPER SIZE: 8.5in SUPPLIER: Tandy dealers NAME: Canon PJ1080A PRICE: £497 SPEED: 37cps INTERFACES: Centronics PRINT METHOD: 7-colour ink jet PAPER SIZE: 8.5in SUPPLIER: Canon dealers, Keyaki [redacted] NAME: Commodore MPS-801 PRICE: £395.95 SPEED: 38cps INTERFACES: CBMIEEE PRINT METHOD: Dot matrix coloured ribbon PAPER SIZE: 8.5in SUPPLIER: Commodore [redacted]

A comparison of the speed and capabilities of thermal printers puts the HR5 well in front.

The Brother HR5.

The Brother M1009.

The Canon PW180A.

The Epson RX80 F/T.

The GP-700-A is good value, but the Integrex offers more features. Above, the Commodore MPS-801.

The Smith Corona D200.

The dot matrix market is competitive, and price is not always the best indication of what's best.

With letter quality printers, you get what you pay for.

Personal Computer News

Piers Letcher

COLOUR SCHEME Three colour printers are compared by Piers Letcher. More printers now offer entire screen dump facilities, but most have been, limited to black and white printing. Recently new technology, multi-coloured ribbons and colour inkjets have brought the price of colour printers within reach of home computer users, as shown in our Pro-Tests of the Seikosha GP-700A, the Tandy CGP-220 and the Integrex Colorjet. We looked at the choice you have for colour results - for people who want more than the four biros on the Atari/Commodore/Tandy... colour printer/plotter. COLOUR INK JET PRINTERS The Tandy CGP-220 and the Integrex Colorjet are repackaged versions of the Cannon A1210 colour ink jet printer. They run almost silently, printing one pixel at a time by squirting ink through a very fine nozzle. To print a line, or character, takes seven runs across the page. Two clip-in cartridges - one black, one colour - provide the ink, thus avoiding ribbon trouble. Special roll feed paper is used, though the printer will cope with single sheets, or tractor feed with the edges torn off. SEIKOSHA GP-700A PRO-TEST: PCN, Issue 20 PRICE: £489 inc VAT TEXT SPEED: 50cps GRAPHICS SPEED: 4-5 mins for full screen dump. INTERFACE: Centronics Parallel, RS232 serial (£50 extra) CONTACT: DRG (0934) 419914. COMMENTS: This was the first cheap full colour printer, halving the cost of anything previously available. It operates (unusually) by having four wedge-shaped hammers hitting a multi-coloured ribbon - overstriking can be used to mix colours. By dot matrix standards the printer is both bulky and noisy (due to four hammers striking in unison). Its ribbons tend to get messy since the ink merges across the four bands, though this can be cured to some extent by putting the printer into self test mode to revolve the ribbon. Its documentation also lets it down. Although most of the necessary information is included, it's aimed at experienced users. But it has the advantages of speed (at the expense of silence) and paper versatility - the others use roll paper whereas this will take tractor feed or single sheet. INTEGREX COLORJET PRO-TEST: PCN, Issue 44 PRICE: £575 inc VAT TEXT SPEED: 37cps GRAPHICS SPEED: full screen dump 6 mins, half size full screen dump 1.5 mins INTERFACE: Centronics parallel, RS232 serial (£140 extra), Viewdata including Centronics and RS232 (£165 extra). CONTACT: Intrgex (0283) 215432 COMMENTS: Although the Colourjet is the most expensive of these three printers, it is the most versatile. It is primarily for BBC and Apple users, but with Centronics as standard and RS232 as optional it works with almost any machine. A BBC graphics dump program listing comes with it, and in March there will be software for an IBM high resolution dump. The internal software allows you to do double strike and double resolution while in text mode, and though this slows the printer further, the results are impressive. TANDY CGP-220 PRO-TEST: PCN, Issue 39 PRICE: £499 inc VAT TEXT SPEED: 37cps GRAPHICS SPEED: 6 mins for full screen dump. INTERFACE: parallel for Tandy colour computer, and switchable serial 600/2400 baud. CONTACT: Tandy Computer Games COMMENTS: The CGP-220 is cheap, quiet and of high quality, though unfortunately if is difficult to attach to anything except a Tandy. This problem is caused by Tandy's pins being slightly different from the Centronics standard. Also, when hitched up to anything else you have to write the program to get your screen dump. Printing characters is fairly slow, but elongated and colour characters are easily selected with control codes.

Over the past few months PCN Pro-Tested new printers that drastically reduced the cost of colour printing. Their merits are compared here and depicted in a PCN printer's pie. This indicates the trade off between the four major variables - Note that the cheaper a printer is, the larger its slice of the pie, and therefore the smaller the price/performance gap.

Your Computer

David Horne

David Horne with a quick guide to the best printers on the market. There is a very large and bewildering choice of printers available for the computer hobbyist and not a great deal of published work regarding the suitability of the machines for specific tasks. It is not possible to look at all the combinations of computers and printers but I hope to give a guide as to what can be expected from printers in each price bracket. I have also highlighted the points that the user should evaluate when contemplating the purchase of a printer. The factors will be weighted differently depending upon whether the required use is business, educational or hobbyist. For this reason I have simply stated the advantages and disadvantages of each approach. The machines reviewed are all very good value for money and have been chosen on the basis of offering the most facilities within a given price-bracket. As a general introduction it should be said that ideally a printer should have both Centronics and serial interfaces. It is logical that as the number of homes with more than one computer increases, whether it be one computer per child or just a spare computer, that each computer should be able to share the expensive peripheral devices that are used infrequently. The annual/biannual cost of upgrading your system can be significantly reduced by purchasing a printer with the common interfaces - RS-232 and Centronics, although just as the last few years have seen an enormous expansion in the areas in which home computing is used, the same is about to happen to the printer. What this actually means is do not buy a badge-engineered product if it has reduced facilities i.e., either the RS-232 or Centronics interface removed, unless there are overwhelming financial reasons for doing so. It could provide a limitation on your future choice of computers. The two current main uses of a printer are to obtain listings of a Basic program and to perform word-processing activities. All the printers are suitable for producing listings. Some users may like wide listing paper so that comments may be added to the right of the relevant lines of Basic, but usually these would be added as Rem statements. The reason normally given for adding comments separately from the listings is either program security - it makes it easier for someone else to follow if a program is correctly annotated - or that the comments can be written in a different colour and therefore stand out much better, enabling the reader to gain a better insight to the workings of the program. With the limited memory available on many machines, the use of valuable RAM working space on formatting neat program notes for easy reading - if it is not neatly tabulated it will not be very easy to see the remarks - is not something that the user will usually contemplate. The advent of the very popular four-colour printer plotter enables the user to provide his own listings with remarks coloured for easy viewing. Inserting a pen which has run out of ink into the appropriate colour pen holder - you must not run the mechanism with a pen missing - will provide copies without visible remarks. It took me ages to think of this use for an old dried up pen. Waste not want not. For word-processing the needs of the enthusiast are not the same as the small business. Generally speed is not that important as the quantity of processed text will be small. The requirement for an A4 print is also not quite such a necessity, as it is just possible to get away with less. For instance, sending text to a magazine in 40 column format will generally be OK as that is how we print it. Accepting that narrow text is in certain cases permissible, it should only be considered as an interim solution until finances permit the acquisition of a A4, 8 inch wide paper, printer. Another consideration for word processing systems is lower case descenders. This is the portion of the printed character that is below the general base level of the printed capital letters i.e., the lower case letters g, j, p, q and y. If these sit up on a line the text can become difficult to read, with problems in differentiating between the g, q and 9. All the printers will work within a normal office environment without creating a significant noise problem, but the dot matrix printers and the ZX printer can cause a disturbance in a domestic environment especially late at night. In this respect the ink jet and thermal printers are the most suitable, but clearly do not have the capability of producing multiple copies from multi-part paper. I know it's obvious but with the colour matrix printer, only the original is coloured, the carbon copies are black and white. One of the main uses to which printers will be put in the very near future is electronic mail. Messages can be transmitted to suitably equipped sites at 1200 baud, usually at less cost than posting a first class letter, which should arrive the next day, or of sending the message orally over the telephone. Think of all the post that you send and how much of it could be serviced in this manner including the payment of bills using a credit card facility. It could be seen in today's climate as a way of greatly reducing costs in a very labour intensive industry. The development of electronic mail is dependent upon the advent of very cheap Modems, which are also responsible for holding back the demand for access to large database networks. We really are very close to the electronic communications age, not just for big business but also the general public, with all its obvious advantages and sometimes not so obvious perils. I hate to think what is actually going to happen to the network when the 'enthusiast' gets hold of it with an intelligent terminal; with the new electronic exchanges I can not see how it will be stopped. A printer uses what is euphemistically called consumables. These affect the ability of the user to actually print hard copy output, tn an office, if the printer runs out of paper, either to to the stationery cupboard and get another box or get some from a local stationery stockist. It is not quite that easy in the evening at home, a hobbyist is unlikely to carry a large range of spares so it is worth considering what levels of spares is required. A ribbon can dry out if left for any length of time unused and exposed. In such cases, wind the ribbon back and forth to wet it from adjacent inked portions of the ribbon. Always cap ink pens when not in use. If these run out then you're stuck. Users of the four-colour printer mechanism may prefer to purchase replacement pens from a Sharp stockist who provides packs of four pens - one of each colour. Ensure that if the equipment is battery operated, the batteries have sufficient charge to produce a clear print, otherwise use the main adaptor. As a general rule, roll paper as supplied is less likely to contain creases and is also less likely to jam. If you use fan fold paper, there may be a requirement for a form feed, otherwise printing over the perforated tear may occur, which besides being difficult to read, creates a lot of printing noise. The space requirements of fanfold paper is much greater than that of roll paper behind the printer, think very carefully about how and where you intend to install your printer. It is not usually a problem. Note that all examples are actual size. The cost of the Seikosha 700A featured on page 107 is about £440 and not £725 as indicated. Other prices should only be taken as a general guideline. TANDY CGP-115 Price: £149 Speed chars/sec: 12 No. Chars/line: 80 Type of paper: Plain Paper width: 4.5 length: 150' No shts: N/A cost: £4.99/3 Cost of pens: £1.99/3 ribbons: N/A PRINT CAPABILITY (Yes/No) Upper/lowercase: Yes Graphics: Yes Screen dump: Yes Colour: Yes INTERFACES RS232: Yes Centronics: Yes A colour printer that has virtually become the standard, in many different badge engineered forms. Capable of high quality plotting and of screen dumps in colour. Low noise level and very good quality print but a trifle slow. Has limited capability of setting different print para meters, i.e. Carriage Return or Carriage Return and Line Feed. CONTROLS CHR$ 8 Backspace CHR$ 10 Linefeed CHR$ 11 Reverse linefeed CHR$ 13 Carriage Return CHR$ 17 Set text mode CHR$ 18 Set graphic mode CHR$ 29 Change colour There is also a range of controls in graphics mode to enable the printer to operate as a four-colour plotter. TANDY CGP-229 Price: £499 Speed chars/sec: 37 No. chars/line: 91 Type of paper: Plain Paper width: 8 length: 135' No shts: - cost: £9.95/3 Cost of Ink cartridge B/W: £6.95 Cost of Ink cartridge col.: £9.95 PRINT CAPABILITY (Yes/No) Upper/lowercase: Yes Graphics: Yes Screen dump: Yes Colour: Yes INTERFACES RS232: Yes Centronics: No A very high quality 7-colour ink Jet printer capable of excellent text and graphics performance. Very easy to load and unload ink cartridges, which can quickly be set 'off' for long periods of no use. Quiet in operation. The character set is in two parts with the 'sign' in what is called the 'European set' at CHGR$ (163). Colour resolution is 320 pixels across the paper although the dot resolution is 640 because the colours tend to mix. Each ink cartridge is sufficient for about 8 rolls of paper. Centronics and serial interfaces. CONTROLS CHR$ 10 Linefeed CHR$ 13 Carriage Return CHR$ 18 Bit image graphics CHR$ 28 Repeat commands CHR$ 30 Exit bit image TANDY TP-10 Price: £80 Speed chars/sec: 30 No. chars/line: 32 Type of paper: Thermal Paper width: 4" length: 65' No. shts: N/A Cost: £2.80/2 Cost of pens: N/A ribbons: N/A PRINT CAPABILITY (Yes/No) Upper/Lowercase: Yes Graphics: Yes Screen dump: No Colour: No INTERFACES RS232: Yes Centronics: No Currently the cheapest RS-232 printer on market. The quality is extremely good but limited to 4 inch wide paper and 32 chars. The printing is very quiet spoilt by a comparatively noisy line feed ratchet. Graphics capability is limited to quarter character cell blocks. There are no lower case descenders in the character set. Currently the best print quality for under £100. BROTHER EP-22 Price: £170 Speed Chars/Sec: 17 No. Chars/Line: 75 Type of paper: Plain/Thermal Paper width: A4 length: - No. shts: N/A cost: £2.85 for 100 Cost of pens: N/A ribbons: £5.70 for 5 PRINT CAPABILITY (Yes/No) Upper/lowercase: Yes Graphics: No Screen dump: No Colour: No INTERFACES RS232: Yes Centronics: No A portable printer that can be used as a typewriter, a calculator and as a word processor, capable of storing approx one page of A4 text with the power switched off. Currently the cheapest 'wide' paper printer. I would have liked to use it to enter data into the computer but nonetheless a very good printer. The keys are a trifle 'light' with no audible feed beck. The 16 character LCD display shows what is being typed in and allows a measure of text correction. This is a new concept in printers. There are no lower case descenders. CONTROLS CHR$ 8 Backspace CHR$ to Linefeed CHR$ 13 Carriage return (as selected) SEIKOSHA GP-250X Price: £260 Speed chars/sec: 50 No. chars/line: 80 Type of paper: Plain Paper width: 10" length: N/A No. shts: Cost: £15 for 2,000 sheets Cost of pens: N/A PRINT CAPABILITY (Yes/No) Upper/lowercase: Yes Graphics: Yes Screen dump: Yes Colour: No INTERFACES RS232: No Centronics: Yes A very good business machine but not really suitable for the home where the noise and installation may be a problem. Cover removal is required to gain access to switch selectable functions including baud rate. Dual Centronics and serial interfaces. Paper feed not very easy to use. Has control over print operations, with form feed and lines/page. CONTROLS CHR$ 7 Bell CHR$ 10 Linefeed CHR$ 12 Formfeed CHR$ 13 Carriage Return CHR$ 14 Double width characters CHR$ 15 Standard characters CHR$ 16 Print start position address CHR$ 20 CR without LF (DC4) CHR$ 27 ESC commands CHR$ 28 Repeat SEIKOSHA 100A: Price: £215 Speed chars/sec: 50 No. chars/line: 80 Type of paper: Plain Paper width: 4-10" length: N/A No. shts: N/A cost: Cost of pens: ribbons: PRINT CAPABILITY (Yes/No) Upper/lowercase: Yes Graphics: Yes Screen dump: Yes Colour: No INTERFACES RS232: No Centronics: Yes One of the cheapest dot matrix printers with graphics capabilities. Can be used with two part paper to produce carbon copies. The top cover has to be removed to gain access to CR or CR/LF switch. Paper feed not very convenient, can be upgraded for RS232, the cassette ribbons easy to install. A UK character set may be used which puts the £ on Shift-3 key. No lower case descenders. CONTROLS CHR$ 8 Backspace CHR$ 10 Linefeed CHR$ 13 Carriage Return CHR$ 14 Double width characters CHR$ 15 Standard characters CHR$ 16 Print start position address CHR$ 20 CR without LF (DC4) CHR$ 27 Horizontal dot address CHR$ 28 Repeat command SEIKOSHA 700A: Price: £725 + VAT Speed chars/sec: 38 No. chars/line: 106 Type of paper: Plain Paper width: 10" length: 11" No. shts: 9.5" cost: £16 for 2,000 sheets Cost of pens: N/A ribbons: £2.50 PRINT CAPABILITY (Yes/No) Upper/lowercase: Yes Graphics: Yes Screen dump: Yes Colour: Yes INTERFACES RS232: No Centronics: Yes A very nice looking colour printer that has the ability to produce colour screen copies. Each pixel is colour addressible. There is software control over formfeed and lines/page. Centronics interface only. There is a copy command for screen dumps. When the optional extra screen dump board is installed. Does not appear as noisy as the two less expensive Seikoshas. CONTROLS CHR$ 10 Linefeed CHR$ 12 Formfeed CHR$ 13 Carriage Return CHR$ 14 Double width characters CHR$ 15 Standard characters CHR$ 16 Print start position address CHR$ 20 CR without LF (DC4) CHR$ ESC commands CHR$ 28 Repeat commands ZX PRINTER Price: £40 Speed chars/sec: 50 No. chars/line: 32 Type of paper: Metallized Paper width: 4" length: 65' No. shts: N/A cost£ Cost of pens: N/A ribbons: N/A PRINT CAPABILITY (Yes/No) Upper/lowercase: Yes Graphics: Yes Screen dump: Yes Colour: No INTERFACES RS232: No Centronics: No Probably the cheapest means of producing hard copy output from a computer. Special Sinclair interface prevents its use without an adaptor on other computers, at which price you should consider other printers. The metallized paper rolls are of variable quality and can produce faded bands of printing. The accumulation of particles inside the printer affect the drive logic leading to alternate line offsets and father peculiar characters. The printer is also prone to become noisy after prolonged use. The solid bar roll holder is a useful accessory and helps in overcoming the initial sticking of the paper drive. Very fast COPY, LLIST and LPRINT. Plotting and user defined graphics available. NEC PC-8221A Price: £80 Speed chars/sec: - No. chars/line: 40 Type of paper: Thermal Paper width: 3 length: 150' No. shts: - cost: £ Cost of pens: - ribbons: - PRINT CAPABILITY (Yes/No) Upper/lowercase: Yes Graphics: Yes Screen dump: Yes Colour: No INTERFACES RS232: No Centronics: Yes Currently the cheapest Centronics and the cheapest dot addressible printer on the market. Exceptional value for money. Run by four penlight batteries or a mains adaptor. Limited paper width of 3 inch. Very quiet in operation end completely portable. CONTROLS CHR$ 10 Line feed CHR$ 13 Carriage return CHR$ 14 Double size printing CHR$ 15 Standard printing CHR$ 27 ESC Used to produce user defined graphics which may be 16x16 pixels in size. OLIVETTI INK JET Price: £400 Speed chars/sec: 66 No. chars/line: 132-80 Type of paper: Plain Paper width: 8-9" length: N/A No. shts: £15 for 2,000 sheets cost: £ Cost of ink: ££7.50 PRINT CAPABILITY (Yes/No) Upper/lowercase: Yes Graphics: Yes Screen dump: Yes Colour: No INTERFACES RS232: No Centronics: Yes A very fast quiet ink jet printer with manual control of the print intensity Capable of very high quality graphics. I could not use the roll paper as the machine was supplied without a left hand support bracket. CONTROLS CHR$ 7 Bell CHR$ 9 Horizontal Tabulation CHR$ 10 Linefeed CHR$ 11 Vertical tabulation CHR$ 12 Formfeed CHR$ 13 Carriage Return CHR$ 14 Double width characters CHR$ 15 Standard characters CHR$ 16 Print start position address CHR$ 20 CR without LF (DC4) CHR$ 27 ESC commands CHR$ 26 Repeat commands

Personal Computer News

David Janda

Item: Seikosha GP-700A colour printer INTERFACE: Centronics parallel, RS232 (optional extra) SPEED: 50cps MANUFACTURER: Seikosha PRICE: £425 plus VAT SUPPLIER: C DRG [redacted] SEIKOSHA'S RAINBOW PRINT Tired of grey, lifeless listings? David Janda tests a printer that will put colour in your hard copy. Until the arrival of the GP-700A, full-colour printers were the preserve of people with at least £1,000 to spend. The GP-700A can be claimed with, justification to represent a price breakthrough because it is capable of full-colour text and graphic printing for the comparitively modest outlay of £425 plus VAT. The question is, of course, whether this pricing indicates limitations in performance. FIRST IMPRESSIONS A display panel on the right features three indicator lights and four push-buttons. The lights indicate 'Power', 'Paper-empty' and 'Copy' the buttons executive 'Stop', 'Line feed', "Form feed', and 'Copy'. The Copy button engages an optional copy board (estimated to cost £60-£70) which gives you a screen-dump (in colour of course). The test model didn't have one of these and graphic production involved addressing the dots - a real headache. The noisy moving bits are covered by a transparent plastic panel. This is removable but is a very necessary element for it reduces the noise significantly. It has to: this is the loudest dot matrix printer I have ever encountered. It sounds like someone is using an electrical circular saw in the next room. Feed methods are either tractor or friction-feed. It isn't necessary to remove the sprocket holders for friction feed as there is ample room. The cassette holds a length of continuous ribbon and four ink cartridges - yellow, magenta, cyan and black. Extra colours are available by mixing (overstriking) different primary colours under software control. SETTING UP This is simplicity itself. Although I thought I would have trouble removing/replacing the ink cassette all that was needed was to turn the central spindle on the cassette, press the release lever and lift gently - three seconds at most. Inserting the continuous paper was just as easy because the tractor holders slide smoothly across the friction bar - fine adjustment is no problem. Paper thickness is catered for with eight head adjustment positions. The only real grumble I have about the process of getting up and running is trying to access the dip switches inside the printer. Six screws have to be undone and the cover of the printer gently lifted off. The dip switches allow you to change the four European character sets. The Centronics interface is at the back of the printer. Documentation Yuk! It's clear that documentation was last on the list of priorities. The inexperienced user is in for a shock. Everything starts off simply enough. 'This is a plug, this is a printer' and so on; but the description of the control codes is enough to boggle the brain. Although all the necessary information is there it's written for the person who is going to install the printer as part of a system. All the control codes, dip switch settings and so on are included but necessary information such as recommended paper and maintenance advice is wholly lacking. I can see GP 700A users jamming their dealers' switchboards. To give programmers an idea of how things are done there is a sample program at the back of the manual. Again, this is fine for the programmer, but for the everyday owner confusion is a certain companion. FEATURES Its biggest feature is the ability to print in seven colours. It will allow printing of any colour within the line or pixel. This means that a screen dump of, say, the BBC's mode I in colour is theoretically possible. With all the control codes necessary to undertake the exercise many users may find the copyboard an attractive option. For ordinary characters, however, it is possible to change the colour quite easily. LPRINT CHR$(20) + CHR$(2) + 'hello' will print 'hello' and subsequent characters in red. The colours can be changed by writing a different control code to the printer. A word of warning - if you're interested in this printer it's essential that you make sure your applications programs are compatible. With some word processors, for instance, the control codes used to format the text may be interpreted by the printer differently. This is not the fault of the GP-700A; it's an inherent problem with printer buying. Most of the operations of the printer can be controlled by software - writing codes to the printer. Line feed and carriage return can be sent individually if desired ind there are three ways of setting line spacing. It may be set to 1/8 or 1/16 of an inch or if you really want to be flexible, you can set the line feed to n/120 inches where 'n' is a number less than 99. Character spacing can be set to 10 or 13.3 characters per inch. When this is mixed with the option of double width printing, you effectively have four different sized typefaces. Page length can also be specified by either number of lines per page or by inches per page. You must be careful if you are to take the first option and then use large characters - you could end up in a mess. Tabulation is not supported, but it is possible to specify the print position within a line by sending a three digit decimal number. When it is used in dot graphic mode, it is possible to specify the print position down to a single pixel. One handy feature is the facility to repeat characters. By doing this it is possible to do long underlinings without having to enter a long string. It is possible to print individual dots in any of seven colours anywhere on the pages. Normal text can be interspersed with graphics of your own design. The printer does not have any graphic character sets and it is left to you to send graphics data to the printer. To do this you can make whole characters one colour, or you can specify colours by RGB raster scan or hammerhead scan. This level of control means that the GP-700A must be one of the most flexible dot matrix graphic printers available, if all this sounds a bit daunting, professional help is apparently on the way. DRG, the 700A distributor, is busily drumming up third party software and hardware support. An Apple card for screen dumping to the printer is on the drawing board, expected to cost £65 to £75. For BBC owners there is a possibility that Cloud Techniques Colour Palette box will also be supported with the necessary software to download its graphics. The company is also considering selling the necessary control program by itself. The standard copy board from DRG is expected to cost £60 to £70. UP AND RUNNING Turning on the printer and holding down the line-feed sets off the self-test mode. All the characters are printed in glorious colour and at this stage the most disappointing aspect becomes clear. The black print on the test model was slightly blurred while all the other colours were fine. I checked the paper, ribbon and ink cartridge but all was well. Setting the head adjustment did no good either so I can only put it down to the type of ribbon used. I hope this problem is solved because although this printer's main feature is obviously colour, users are bound to want standard text output for the money. The speed remained at a constant 50cps. Even when unusual combinations of colours are being executed the head requires only one pass to overstrike (see box opposite). The friction feed was very good: even when using continuous paper it never wavered. Using single sheets meant that 1.5 inches of space was reserved at the top and bottom of the sheets and this is quite acceptable. Two handy maintenance features: the paper debris picked up by the ridged platten was easily cleaned off. It's necessary to do this quite often. Also, when printing with different colours, parts of the ribbon tended to get smeared with another colour. One way to get round this is to put the printer into self-test mode without paper. This revolves the ribbon and gets the ink to the right places again. VERDICT The Seikosha GP-700A is a significant step forward in colour graphic printing and will be useful to people who need or want colour. It has many features that you wouldn't expect for the price. Used with the planned graphics systems it should make a rewarding output device for the hobbyist, and provide a valuable tool for the designer. To access its wonders, however, requires either additional hard or software, or patience and aptitude.

Colour close-up. The GP-700A's unusual print mechanism is a change from the usual wire-plan hammer,. See box (left) for details of how this printer gets dots onto paper.

A high printer capability in one direction will probably cause either a low capability in another or a higher price. If a printer has lots of everything it will close the price/performance gap.

The reason the GP-700A is so noisy becomes apparent when you understand the way it gets those coloured dots onto paper. A conventional dot matrix printer knocks dots through a ribbon by striking selected elements from a row of pins. The GP-700A gets its matrix effect by doing something very different. It runs a row of four vibrating wedge-shaped hammers down a ridged platten - represented in the disgram by the black object (the arrow indicates the direction of its spin). Although it's represented here in 'cross-section', from its front it looks like an elongated gear wheel. It is positioned horizontally behind the paper and its ridges, whcih run length-wise down its circumference, are spaced a character-length apart. As the platten spins the wedge-shaped hammer opposing it is vibrated against the ridges as they pass, punching columns of dots from the ribbon to the paper to build up the characters. The clever thing about this technique is that it enables extra hammers to be lined up to share the platten. The GP-700A runs a length of continuous ribbon at a 45 degree angle across the printhead mechanism. The ribbon is four-coloured and is topped up by replaceable ink cartridges. There is one hammer postioned over each colour band on the ribbon. As the printhead runs down the platten and across the paper it can overstirke colours or mix them in the one character matrix, starting with yellow, then magenta, cyan and black.