Tuesday, April 28, 2009

The Dell 0636U monitor

Notes from troubleshooting why this monitor sucks so much, prior to resolution.

Monitor was part of a rack-mount drawer system, very nice with a tiny keyboard and trackball and hinge that allows the LCD screen to be stowed flat.

When hooking up the monitor to a PC, I get a blue screen with a red box containing a flashing message along the lines of "Invalid PC Mode H:48Khz V:10Hz"

Googling this, there are hundreds of hits, each with a slightly different wrong mode indicated. By and large they are almost all from souls attempting to get this monitor working with a Linux box of one flavor or another. The most informative results for Windows based inquiries were:

This "majorgeeks" forum http://forums.majorgeeks.com/showthread.php?t=52316 where it was pointed out that the refresh rate being output by the graphics card might need to be adjusted, although it suggested 75Hz,

A single-page PDF of a service manual for the monitor http://support.dell.com/support/edocs/monitors/fprack/En/trouble.pdf mentions the exact problem but unhelpfully refers to a "Support Timing Table" that I have not been able to find.

This Dell forum http://lists.us.dell.com/pipermail/linux-poweredge/2004-August/015998.html, reproduced endlessly throughout Dell's web site like a great echo chamber, where a guy asks for the specs on the stupid monitor and a link to a Dell manual is given.

The Dell manual, http://support.dell.com/support/edocs/acc/4292e/ is a 5-part website that disturbingly lists a different model number for the monitor under the monitor specs, along with crazy looking screen and refresh rate specs, but under Tech Notes it states that the resolution is 1024 x 768 with a rate of 72Hz.

This correlates somewhat with one of the other hits for the monitor, a surplus dealer that lists it as a 1024 x 768 monitor. Interestingly, yet another surplus dealer lists it as an "XVGA" monitor. What's XVGA?

My PC has a Quadro2 EX graphics card, which does not support 72Hz. A spec for the Quadro2 EX can be found at page 28 of this spec for an HP tower http://www.ctmsolutions.com/download/postproduction/HP_CPUHPW8000_specif_US.pdf . Nvidia's website seems completely useless and I was unable to dig refresh rate specs out of it for any card. The GeForce 4 from the same tower spec seems to support 72Hz.

One of my other Dells has a spare GeForce FX 5200 video card, as seen here http://www.techexcess.net/nvidia-geforce-fx-5200-128mb-video-card-8x-agp-dell-g0170-f1810.aspx, but it does not support the 72Hz

Tuesday, April 21, 2009

Beating a jpeg of a line image back down to monchrome

Technique for converting 24-bit jpegs to B&W bitmaps:

1) (possibly optional) save as a 4 bit bitmap
2) Set gamma correction to 0.01 (in IfFanView, possibly in other programs, under color correction)

Note: The pinout images, possibly stolen from Norcomp can be seen at interfacebus.com:

http://www.interfacebus.com/Connector_D-Sub_Mechanical_Dimensions_Insert_Arrangements.html

Thursday, April 16, 2009

Procedure for capturing documents to bitmaps

A method for creating drawings in Word or PPT and then formatting to a bitmap for importing into an OrCAD drawing:

1. Send document to a PDF (for example by using PrimoPDF)
2. Open PDF using Adobe 9, select the image to be exported using the capture tool.
3. With the image still selected after the automatic capture, use the view setting to expand the view as large as feasable to get nice smooth rendering on text and lines (most frequently used setting: 300%). Then hit CTRL-C to copy the image again, this time at the higher resolution.
4. Paste the image in either MS-Paint or IrFanView, manipulate the size and color depth.
5. The maximum size picture that can be imported into OrCAD seems to be dependent on the total number of pixels (approximately 2.5 MPixels). For the front panel that was a width of 2540 pixels but for the top view that limits it to a width of 1700 pixels.
6. The picture resolution when printed is much better than on the screen.
7. Can size the picture based on plain lines drawn in OrCAD for reference.