Author Topic: IFU-30 RGB mod horizontal noise?  (Read 299 times)

nam9

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IFU-30 RGB mod horizontal noise?
« on: June 09, 2017, 11:50:35 AM »
Hi.
RGB modded an IFU-30 unit a while ago.
Hooked up to my main TV and I notice horizontal bands of noise across the upper portion of the screen and general noise throughout the blacks in the picture (Picture, Video).
I am using a 9V 1.5A PSU from RetroGameSupply, but issue persists with different adapters as well.
Tested without CD-ROM drive installed and with diffreent Core Grafx unit, so problem down the the IFU itself...

Not sure if similar to this issue. The lines are persistent towards the top of the screen..

Any thoughts? Cheers!

gtsamour

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Re: IFU-30 RGB mod horizontal noise?
« Reply #1 on: June 09, 2017, 08:47:42 PM »
If I turn up the brightness on all my RGB modded PCEs there's always "something" lurking in the black parts. I think they are normal and are only seen in LCD tvs. These consoles were made to be played on CRTs and analog picture signals are never 100% clean.

Specially on the PCE TG16 CD systems and during loading I can see faint waves going up or down if the brightness is high enough, so your case (IFU-30) falls in this category too.

If you turn the brightness down you'll see that after a point these are not visible anymore and the picture is still very well lit.

So... after looking at your video and picture, I think this is normal.
The guy in the link you posted seems to be having an entirely different issue. I had his issue too when I used an insufficient psu (lower amps than needed on a pce duo).

Ps
A crappy or insufficient PSU can make these kind of distortions A LOT worse.
A Low quality RGB cable  can make these kind of distortions A LOT worse.
Don't expect these kind of distortions to go away completely even if you have good quality psu and cable.
« Last Edit: June 09, 2017, 08:58:26 PM by gtsamour »

nam9

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Re: IFU-30 RGB mod horizontal noise?
« Reply #2 on: June 09, 2017, 11:47:15 PM »
Thanks for the feedback.. I have a couple things I can still test...
I have a different PSU, but it is a 9.5v 2.5A one. Will 9.5v be too high?
I have also checked the scart cable and not all the Gnd connections are wired, so I'll fix that...

gtsamour

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Re: IFU-30 RGB mod horizontal noise?
« Reply #3 on: June 10, 2017, 01:41:36 AM »
Your PSU is fine specs wise.
Anything between 9-11V is OK assuming the polarity is correct and the PSU isn't defective or of bad circuit design quality. 1,5A is enough, more doesn't hurt.

As for grounding... no need to ground all the pins.

Use the cable's/pce jack shell ground for the scart sound ground, and the regular pce ground for the composite ground pin on the scart.

Here's my cable



« Last Edit: June 10, 2017, 01:43:52 AM by gtsamour »