So I decided to do some experimenting with one of my SNESs to get rid of the vertical line. I had a 470uf capacitor on the 7805 output and replaced the 7805 with a 2A 78S05, but the vertical line, while extremely faint, was still there.
Basically what I did was put an inductor in series with the output of the 7805 and a 470uf cap on the output of the inductor to ground, and I cannot see any vertical line whatsoever. If anyone tries this and wants to add even more filtering, you could add another capacitor on the output of the 7805 before the inductor to ground, creating a pi filter, but I haven't tried that myself since this seems to be sufficient, and since the input of the 7805 already has a 1000uf filter cap.
Getting rid of the SNES vertical line once and for all.
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syboxez
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Xaranar
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Re: Getting rid of the SNES vertical line once and for all.
What inductor did you use? And which model of SNES?
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syboxez
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Re: Getting rid of the SNES vertical line once and for all.
I used an old inductor from a dead power supply, so I don't know the rating, and the SNES is an SHVC-CPU-01, although it should apply to all SNESs.Xaranar wrote:What inductor did you use? And which model of SNES?
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Xaranar
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Re: Getting rid of the SNES vertical line once and for all.
Interesting. I have a SNES Mini, and although the vertical line is invisible in 99% of situations, it is there, but it isn't white, the screen is completely uniform over the left side of the screen, but just past the centre there is a darkening of the pixels. I'll get hold of an inductor and give it a go, I already have a ton of caps lying around.
Also, can we see pictures?
Also, can we see pictures?
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syboxez
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Re: Getting rid of the SNES vertical line once and for all.
http://i.imgur.com/HcS7X2A.jpgXaranar wrote:Interesting. I have a SNES Mini, and although the vertical line is invisible in 99% of situations, it is there, but it isn't white, the screen is completely uniform over the left side of the screen, but just past the centre there is a darkening of the pixels. I'll get hold of an inductor and give it a go, I already have a ton of caps lying around.
Also, can we see pictures?
No pic of the lack of vertical bar because I'm using a CRT.
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rama
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Re: Getting rid of the SNES vertical line once and for all.
I wonder how this works, ie: how the effects of an inductor play out in this setup.
There's the 7805 trying to regulate to 5V, then several big capacitors that store energy and then there's the consumer, which is probably the DRAM when it refreshes once per scanline.
Well, I've had good success decoupling the DRAM locally with some 1uF SMD ceramics.
This was just what I had in the parts bin though. It's not calculated or anything :p
There's the 7805 trying to regulate to 5V, then several big capacitors that store energy and then there's the consumer, which is probably the DRAM when it refreshes once per scanline.
Well, I've had good success decoupling the DRAM locally with some 1uF SMD ceramics.
This was just what I had in the parts bin though. It's not calculated or anything :p