STANDING IN FOR THE SINCLAIR PRINTER
DEAN ELECTRONICS has announced the introduction of a Sinclair-compatible thermal printer, the Alphacom 32. It is manufactured by the American company which produces the Timex-Sinclair 2040 printer - reviewed in the July Sinclair User. The printer is very different from the U.K. Sinclair printer in both external appearance and print quality but is designed to be just as easy to use. It plugs into the rear connector of either a ZX-81 or Spectrum and will accept the standard commands of LPRINT, LLIST and COPY.
That means it can be used in exactly the same manner as the Sinclair, without alteration to existing software. Using 110mm. wide white thermal paper, it produces a very readable output at a speed of roughly two lines per second.
The printer casing is approximately 195 x 140 x 55mm., black-moulded ABS, with a perspex blister on top which holds the paper. Two thick wires emerge from the back, one about 150mm. long to the edge connector which has a ZX-81-size connector to the computer and a through port for RAM packs and the other to the supplied external power supply by way of a male 3.5mm. jack plug.
Inside the printer there is a minimum of electronics, a ROM chip to handle the printer operations, five chips to control the printing mechanism, a handful of discrete components and two PCB-mounted switches to turn the printer on and off and to advance the paper; the use of both switches together performs a self-test function.
The bulk of the space is taken up with a very solid-looking, rubber-mounted, printer mechanism. The mechanism contains, to one side, a 1 5V motor which, through a series of nylon gears, turns the rubber platen which feeds the paper through and also moves the printhead.
The print head is made of a ceramic material into which are inlaid 20 wires. As they are moved across the paper they burn off the top surface of the paper to leave a black ink impression.
Each wire covers two character squares in a zig-zag fashion which shows up the only disadvantage of the printer. When producing a copy this zig-zag is noticeable on any solid blocks of ink.
The printer becomes warm in use but that is not a problem as there are adequate ventilation slots on the top and bottom and a large heat-sink inside.
One slight problem, however, is that on a Spectrum the edge connector lead fouls the power lead, making insertion difficult.
Priced at £59.95, including power supply and one roll of paper, with extra rolls of paper at only £1, the printer must be seen as a viable alternative to the Sinclair printer.
The Alphacom 32 is obtainable from Dean Electronics Ltd, Glendale Park, Fernbank Road, Ascot, Berkshire SL5 8JB and branches of W H Smith.