Adjusting and Calibrating your Laser

General PSX CD Troubleshooting, PSX CD-ROM Mastering and Disc Creation
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Shadow
Admin / PSXDEV
Admin / PSXDEV
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Joined: December 31st, 2012, 5:37 pm
PlayStation Model: H2000/5502

Adjusting and Calibrating your Laser

Post by Shadow » April 6th, 2015, 11:27 pm

In order to adjust your PSX laser, you will need an oscilloscope. Preferably, an analog one. The digital ones just don't cut it. For the calibration test, make sure you use an original/official PlayStation 1 game. Just load it up and let the game run as normal.

Now, find the test point labeled "CL701". This is the RF eye pattern test point.
It is usually near the servo circuitry.
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This is the test point on a SCPH-7000 board.
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What you're looking for it a voltage ranged from 0.90mV to 1.35V.
Mind you that if you have a modchip and you load a copied CD-R, the voltage will appear lower than when you tested with an official PlayStation format CD-ROM.

You can see here, it is a little low.
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After turning the pot on the ribbon cable house on the CD-ROM mechanism itself, it started to increase in power.
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Development Console: SCPH-5502 with 8MB RAM, MM3 Modchip, PAL 60 Colour Modification (for NTSC), DB-9 breakout headers for both RGB and Serial output and an Xplorer with CAETLA 0.34.

Development Computer: Windows 98, Pentium 3 [400MHz], 128MB SDRAM, DTL-H2000, DTL-H201A, 21" Sony Trinitron CRT, CD-ROM burner, 3.25" and 5.25" Floppy Diskette Drives and a ZIP 100 Diskette Drive.

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