We have received two printers for the Sinclair computer, one from Sinclair and the other from Mindware.
THE SINCLAIR PRINTER:
The first thing we noticed about this printer is its compact size. It is only about half the size of the computer but about twice as thick. It uses electro-static thermal paper that works on the following principle:
A normal ink-producing dot-matrix printer has a series of pins that strike the ribbon against the paper. The matrix element that comprises a printed character is a series of dots, where if all were used, would form a box. The most popular matrix is 5 dots across by 7 dots down. The pins are arranged in only the 7 down configuration in a movable device called a “dot matrix print head” or just – “head”.
This head moves along the paper with the pins striking the ribbon in such a manner as to produce the desired characters.
A thermal printer uses the same concept but instead shoots a spark from the print head at the paper. The paper has metallic particles in it and completes an electrical circuit that is started by the electrically charged print head.
The Sinclair printer works fine except for one problem. The paper won’t feed properly. New lines may be printed over existing ones. This problem started occurring after about 50 lines were printed. I haven’t tried making any adjustments yet so it might be something that can easily be overcome. In the meantime, I physically pull the paper each time I need a print-out. I have talked to other people who had received this printer and no one else had this problem, so I’m sure it’s not common.
The printer easily hooks up to the computer by plugging directly into the back of the computer with the rampack, if used, completing the sandwich connection. It needs no power supply of its own but the power supply should provide at least one amp of current. Sinclair provides a one amp power supply with each unit.
If you do decide to order this printer, make sure to ask about extra rolls of paper. They are the only people I am aware of selling this printer and the paper.
THE MINDWARE PRINTER
A very impressive unit almost the size of the computer and about twice as thick. This device prints on standard 1 3/4 inch adding machine tape with a micro-ink cartridge. This cartridge is the same type as used on the Sharp and Radio Shack pocket printing calculators. The Sharp part # is EA-800R. We don’t have the Radio Shack part #.
Ed. Note – our thanks to Sheldon Weinburg of Brooklyn, NY for this information about the ribbons.
One of the things that bothered me about this printer was that it could only print 16 columns. I thought that the only way to get readable text such as a program listing was to print the left side of the program and then the right side and then paste the two sides next to each other. Although this is true, in many cases it is not neccessary.
The computer has three print modes, where when mode (0) is used, the printer is instructed to print the first 16 characters of the line and then prints the second or remaining characters under the first line of printed characters and starts the process over again. Therefore the program:
10 LPRINT "ABCDEFGHIJKLMNOPQR"
20 LPRINT "STUVWXYZ0123456789"would be listed as:
10 LPRINT "ABC
DEFGHIJKLMNOPQR"
20 LPRINT "STU
VWXYZ0123456789"Perfectly readable and easily understood. The other 2 modes will allow the split printing and printing of just the first 16 characters of the lines whether it be a listing, using the COPY command or the LPRINT command.
The Mindware MW-100 printer also comes with its own power supply which is hooked up directly to the printer and the computer power supply is left disconnected. The computer and printer both derive power from the MW-100 power supply as the current is back-fed into the computer.
Mindware is planning to sell these printers strictly through store outlets. It took a long time for them to receive FCC approval for this unit but I believe it is the best available for the price. It has the potential to print mailing labels and if coupled with an easily revised version of our CUSTOMER FILE program that appeared on the 10/82 cassette, one could easily cut the paper tape into labels and paste them on envelopes.
Both printers came after a 30 day wait and are or were available from:
ZX-PRINTER – 99.95 – Gladstone Electronics, 1585 Kenmore Ave., Buffalo, NY, 14217, 1-800-833-8400
MW-100 PRINTER – 119.95 – Mindware Inc., 15 Tech Circle, Natick, MA, 01760, (617) 655-3388