SX PARTS CATALOG

PRINTERS AND CONTROLLERS
QMS PS-810 Series

QMS-PS 815MR AND -PS 825MR PRINTERS

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Model Information

GENERAL INFORMATION

QMS uses the letters MR as an abbreviation for the Multiple Resolution capability of these two models. The MR printers offer both 300 dpi and 600 dpi. In 600 dpi mode, the print quality is dramatically better but processing takes slightly longer. This is because in 600 dpi mode the controller must develop bitmaps consisting of 360,000 dots per square inch as compared to just 90,000 in 300 dpi mode. For draft printing, the 300 dpi is marginally faster. The PS-825MR is the dual-bin version of the PS-815MR. All other features are the same.

For final output and scanned images, the 600 dpi mode delivers noticeably better print quality on text and much improved bitmaps such as scanned images. This is because 600 dpi yields four times the number of gray scale levels as 300 dpi. Like the earlier QMS-PS 410, 815, and 825 models, these printers feature ESP (Emulation Sensing Processor), SIO (Simultaneous Interface Operation), Font Card slots, and an LCD operator control panel.

The 300 dpi Apple printers, LaserWriter IIf and IIg, take a different approach to enhancing gray scale images than the higher resolution offered by QMS.

FONT INFORMATION

The PS 815MR and 825MR have the 45 resident fonts of the 410, 815, and 825. These fonts are the standard 35 plus 6 styles of Adobe Garamond, and 4 styles of Helvetica Condensed.

REFURBISHED PRINTERS AVAILABLE

The QMS-PS 815MR and 825MR have been discontinued, but The Printer Works can build them from parts at special request. Refurbished printers are in like-new condition and come with a full-one-year warranty. For a price quote, select the printer's part number in the ordering information table.

Controller Notes

Model Information | Supplies and Accessories | Ordering Information | Text Only

The QMS-PS 815MR and QMS-PS 825MR printers use essentially the same circuit board as the non-MR PS-815/825 printers. The printed circuit board etch is exactly the same design. The only difference is that the MR version boards are populated with the extra chips and discrete components that control the laser beam to produce 600 dpi images.

The QMS-PS 815MR comes with 6 MB of RAM, compared with the Apple LaserWriter IIg's 5 MB. The IIg has a faster processor (25 MHz 68030 vs. 20 MHz 68020) and, unlike the MR, it has an Ethernet interface.

For printing text, the 600 dpi of the QMS-PS 815 MR is superior to the FinePrint-enhanced 300 dpi of the Apple IIg (QMS generates four times more dots per inch). This is especially noticeable on small fonts. On scanned images, the results will vary from image to image. The qualitative difference between Apple's PhotoGrade versus QMS's 600 dpi is still being debated, but it appears that 600 dpi may be better where there is a lot of detail in the image, and Apple may have the advantage for smooth continuous changes in tone.

Service providers will be happy to know that they need only to stock one kind of spare controller to support both 815MR and 825MR printers. The 815MR boards function as 825MR controllers when installed in TX-engine based 825MR printers. Only the user definable name should be changed when interchanging controllers between 815 and 825 printers.

Evidently the 600 dpi technology of the MR version was originally developed by DP-Tek and licensed to QMS. This system works extremely well, being the result of extensive empirical research to characterize the real-world of SX toner. It works fine with most SX toner cartridges, but results on scanned images can vary from cartridge to cartridge. To adjust for this variation in toner, QMS includes a special form of dot intensity control called "gamma corrections". The gamma corrections can be changed through software or from the control panel to optimize the 600 dpi output.

Interestingly, the firmware for 815/825MR is the same as that of the non-MR boards. It's able to figure out whether the board has been manufactured for 600 dpi printing and operate accordingly. In order for 600 dpi to work, the extra 600 dpi chips must be installed and at least 4 MB of RAM must be present on the slide-in memory expansion card. If this memory is not there or not working the 815MR will still operate in 300 dpi mode and the 300/600 dpi resolution selection options will no longer be available or displayed on the control panel menu.

The control panel circuit and plastic overlay of the 815 are the same as the 815MR. The control panel circuit is the same one used in the Canon LBP-8II. Switches and LEDs are placed in the same positions, but the colors of the LEDs and the labeling of the plastic overlay that covers the switches is different. Like the Canon printer, 815/815MR control panels have a beeper which is a nice feature that HP printers do not have. The programming of the control panel is dependent on whether the controller is connected to an SX or a TX engine. The 825 printers use a control panel similar to the Canon LBP-8IIT.

Like the 815 board, the SCSI port has not been installed. Also, IC cards with fonts and emulations are not available at the time of this writing. An additional 2 MB can be added by exchanging the 4 MB card for a 6 MB card. The original 4 MB card that comes with the 815MR can be used to add extra memory to an 815, which comes with only 2 MB.

In 300 dpi mode the controller has to rasterize only 90,000 dots per square inch instead on 360,000. Therefore, you would expect that 600 dpi would be much slower. The Printer Works tested the print speed of the 815 MR and found that in 600 dpi mode it was only about 10% slower, a difference too small to worry about. We expect that most 815MR users will simply use the printer in 600 dpi mode all the time. In the 300 dpi mode, the 815MR performance was essentially identically to the 2MB non-MR QMS-PS 815.

Supplies and Accessories

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You can check prices or order these items from the ordering information table below.

TONER

The QMS-PS 815MR and -PS 825MR use the same toner cartridges as all other SX-based printers.

PAPER HANDLING

The QMS-PS 815MR and -PS 825MR printers use the same shaped paper trays and high-capacity feeders as all other SX-based printers. All versions are physically interchangeable, but there are slight color differences. (See also Diagram 300.)

MEMORY

The PS 815MR/825MR comes standard with 2MB on the motherboard and one 4MB expansion card installed for a total of 6 megabytes. The printer will work without this expansion card or with the 2MB expansion card, but only at 300 dpi. The RAM can be increased to 8MB by replacing the 4MB card with a 6MB card.

CONTROLLER UPGRADE OPTIONS

The QMS 815MR is the top of the QMS line for 8-ppm printers. RAM can be expanded to 8 MB.

Ordering Information

Model Information | Controller Notes | Supplies and Accessories | Text Only

For price and ordering information or to place the item in your shopping cart,
select a Part Number in the table.

Model Information | Controller Notes | Supplies and Accessories | Text Only