Testcard Generator (C) Barry Walker. ------------------------------------ With all of today's (April 1999) technology the definitive means of showimg images to the masses is the trusty old Cathode Ray Tube (CRT). Whether it be colour or black and white the "tube" has still to be beaten in price to performance ratio. So I decided to write a program to utilise my old A500 AMIGA as a test tool to set up Colour Monitors/Televisions in PAL/NTSC mode. I may include other modes if there is enough of a response to this program. ---------------------------------------------------------------------------- Safety Notice:- --------------- As with all devices containing a CRT an extremely high voltage appears at the final anode cap (the POPPY), anything from 5KV (small oscilloscope tubes) to 30+KV (colour display tubes), so be VERY careful when making any internal adjustments as a mistake could be harmful at best or FATAL at worst. So again be VERY VERY CAREFUL. ------------------------------ ---------------------------------------------------------------------------- General Information:- --------------------- The program fits onto a standard AMIGA bootable Workbench floppy disk. The disk MUST have a volume label named "TESTCARD". There are also some more testcards in the Testcard directory utilising the various standard AMIGA PAL video modes in the format xx, e.g. 320x256x32 which is obviously standard Lores 32 colour mode. To make the disk bootable consult your AMIGA manual on how install it. If you have a hard disk drive and have booted up the machine from the hard disk drive, place the floppy disk into drive DF0:. Open up a Shell/CLI window from a Shell/CLI icon and type in the following statement:- Copy all df0: to dhx:Testcard where "dhx" is the volume name of the partition you want to install to, and "" is the ENTER key. ---------------------------------------------------------------------------- PC Information:- ---------------- There is also a freeware PC version in the ~TestCard/PC~ directory. It is zipped up using PKZIP.EXE (not supplied), and is approximately 48KB in size. Any type of ANSI.SYS must be disabled from the CONFIG.SYS file (i.e. REM the statement out) and rebooted into a DOS command prompt. Do NOT run through WINDOWS (TM) at all. This is issued under the ~GPL~ terms and conditions. ---------------------------------------------------------------------------- Mouse Pointer Information WB2 and WB3:- --------------------------------------- When the program starts you will notice that the pointer disappears and when you finally Quit the program you have a ~Windows~ type pointer reappear. Do NOT think that you have lost your original pointer you have NOT. The reason for this is that a pointer is needed for normal operation of the AMIGA and there are a lot of people out there who use the standard pointer at bootup and have NOT saved a pointer in the ENVARC:Sys directory, as Pointer.prefs, so therefore I had to generate a pointer for you to use. The simplest way to get your original pointer back is to Reboot the AMIGA, or go to the Prefs directory and run the Pointer program to load your pointer back into the system, assuming you have a Pointer.prefs of your own. If the pointer does not annoy you then click on the ~PAL~ or ~NTSC~ icon. This will work from Workbench1.3x to Workbench3.1x and will keep the mouse pointer on screen all the time. ---------------------------------------------------------------------------- The Program Proper:- -------------------- It is assumed that you have already dismantled the TV/Monitor to access the electronics inside. It is also assumed that you have a manual for the said unit under test or repair. Whether the program runs from the icon or from a floppy boot disk, the first screen will be a serious WARNING screen to remind you of the hazards involved when working with any CRT type of equipment. Press the ~ENTER~ key to continue. The next screen is a Hires testcard of 640x2??x16. This is so that you can adjust any of the external user controls that are available. These will probably be Brightness, Colour, Contrast, Width, Height, Horizontal shift and Vertical shift. When you have done all the preliminary adjustments press the ~SPACE~ bar to continue. You are now in the program proper. If you are a qualified TV/Monitor service engineer then you need not read any further, the program is self explanitory. If you are not then read on. From now on a single capital letter inside brackets means a highlighted letter (e.g. (P) is highlighted P). The mouse is NOT used inside the program. To exit any screen press the ~SPACE~ bar. If there is more than one screen per section then the ~SPACE~ bar will eventually return you back to the Command window. The Highlighted Commands:- -------------------------- (W)hite raster. --------------- This command has 3 levels from dark grey to bright white and is used to check Extra High Tension (EHT) regulation and picture "ballooning". This is generally a design problem and is not adjustable or repairable. (P)urity. --------- This command also has 3 levels, Red, Green and Blue, and is used to check the uniformity of each primary colour raster. The adjustment is usually done with the purity magnets and/or the scanning yoke assembly. Degaussing may also be rquired using a degaussing coil. (S)tatic convergence. --------------------- This command allows a "white cross" generated to be "centred" on the screen and to adjust the the scanning yoke, convergence and shift magnets/controls to produce the best possible centred white cross. (D)ynamic convergence. ---------------------- This command generates a "crosshatch" picture to set all the neccessary controls for best RGB convergence to produce white lines without coloured edges to them. It also helps in the setting up the "pincushion, barrel and trapezoid" error circuits. The adjustments are usually made with the relevant error circuit correction controls. (F)ocus dots. ------------- This command generates lines of dots so that the focus circuits can be adjusted for optimum focus at the extreme corners of the picture, with the best possible focus at the centre. (B)eam limiter. --------------- This command generates bright white and black blocks to check line sync pulling and beam limiting. This is probably a design problem and will not be adjustable at all. It is usually more of a problem on TV systems or CVBS type monitors. (V)ertical sync and (H)orizontal sync. -------------------------------------- These commands check the immunity for a device under test to reject a signal interfering with the sync circuits. This is probably a design problem and will not be adjustable. It may however be a decoupling fault. It is usually more of a problem on TV systems or CVBS type monitors. (I)nterference gratings. ------------------------ This is a none standard test. The command generates a series of black and white vertical lines 1 pixel wide each to create an interference pattern on the screen. There are 2 levels the first is used for TV systems and the second is used for dedicated monitors. It is used to check the shadowmask geometry against the front screen phosphors and the gun assembly. It is purely a check and will never be curable if it is a problem. If you see a pattern like "||||||" then this is a very good CRT. If you see a pattern like "))||((" then this is a good CRT. If you see a pattern like "((||))" then this ia also a good CRT. If you see no pattern at all then you have the perfect CRT (impossible). If you see a random shaped set of patterns then the CRT is poor to average. You may need to vary the brightness to see this effect. (G)ratings for frequency response. ---------------------------------- This is the standard frequency grating test and shows the bandwidth of the video circuits and tube coupling circuits. A TV system may not show the bottom band due to the fact that its frequency limit is approximately 5MHZ. The frequencies are approximately, 500KHZ, 1MHZ, 2MHZ, 4MHZ and 8MHZ. (C)olourbar. ------------ This command generates the 8 colours of the colourbar check. It is used to check colour flaring on very bright and/or very high saturation images and is usually an indication of an aging CRT itself. It is generally a fault and can be curable, but it is probably cheaper to buy a brand new unit. (L)evels of grey. ----------------- This command generates 8 increasing levels of grey to check the black to white linearity of the analogue video circuits. This is commonly known as the greyscale test. (T)estcard. ----------- And finally a repeat of the initial testcard again. It is a Hires screen of 640x2??x16 and is used to reset any external user controls so that it looks correct on the TV/Monitor under test. (A)udio test screen. -------------------- This command places you into a second screen for basic audio tests. Each time an audio test is required the TESTCARD screen will be displayed. On exiting the TESTCARD the sound will be turned off and you will be returned to the main screen for the video checks. The Stereo sound checks. (1) Sinewaves of 400Hz Left channel and 1000Hz Right channel. (2) The opposite of (1). Both are for general audio checks. (3) Both channels 1000Hz for speaker phase checks. (4) As (3) but at 400Hz. Mono sound checks. Connect the left and right channels together (for older AMIGAS only). These two checks are for the RF mode only. (5) 1000Hz Sinewave for aligning the IF and demodulator in TV sets. (6) As (5) but at 400Hz. (V)ideo test screen. -------------------- This command returns you back to the main screen without any audio. (Q)uit. ------- This command will either quit the program into a CLI window or will prompt if you want to reboot the machine, reminding you to remove the floppy disk if it is in the floppy boot drive. ============================================================================ Acknowledgements:- ------------------ First of all many thanks to my wife Tricia who allows me to spend many hours on my computers. Also to David Benn and Herbert Breuer for the ACE/AIDE combination supplied on an AMIGA FORMAT floppy disk which made it easy to compile this program. And to anyone else who I may have neglected or forgotten. ---------------------------------------------------------------------------- Mr Barry Walker, 70 King George Road, Loughborough, Leicestershire, LE11 2PA. Email on either:- wisecracker@tesco.net BYE... ============================================================================