220uF capacitor or uF capacitor?

mrkotfw · Post by **mrkotfw** » Sat Sep 27, 2008 1:32 am

Hello.

I've purchased a XM29 from a person within my city limits and so far I've been extremely happy. One particular problem that I've been having is:

1) The image on the bottom right is slewed in a way. It's rounded. It happens for RGB, composite, and S-video. Though, it varies for consoles and such.

2) When I reset the video options in the XM29 monitor to normal, the contrast percentage is set to normal. There is a lot red bleeding on the screen. I think if I set the 75Ω to HIGH, the image is much, much brighter. But the colors bleed when the contrast is set to normal levels. If I set it too high, the image will start to bleed. This happens to both the PlayStation 1, PlayStation 2, and Sega Saturn.

How can I fix the first problem? Is it the connection that I made (RGB cable) or is it my monitor?

How about the second problem? Do I need 220μF (220. e-6 F) or (0.1 e-6 F) capacitors on each line (R, G, and B)?

How exactly does the 75Ω come into play? I would like to know if it is even safe to use 220μF capacitors? There are also some that advertise 220μF 6.3V ceramic capacitors. The voltage seems correct.

mrkotfw · Post by **mrkotfw** » Sat Sep 27, 2008 7:57 pm

It turns out that if I set the 75Ω to HIGH, the image is darker.

ED-057 · Post by **ED-057** » Sun Sep 28, 2008 5:27 am

1) Sounds like a monitor problem. If the area is also discolored then it's probably magnetization. If it's only the geometry there may be an adjustment to correct.

2) You can try sticking the caps in there, there's no harm in experimenting with different values. Is the bleeding only a problem when using the RGB input?

75Ω is the characteristic impedance of the cable. (I was taught what this meant. I'm not sure if I understood at the time, but I'm sure that I don't now...)

mrkotfw · Post by **mrkotfw** » Sun Sep 28, 2008 8:36 am

Thanks for replying!

ED-057 wrote:1) Sounds like a monitor problem. If the area is also discolored then it's probably magnetization. If it's only the geometry there may be an adjustment to correct.

The geometry is a bit weird. If I play my SNES (composite) or any other system and scroll down on, say a 2-D game, it begins to warp. Will the XM29 manual tell me how to fix geometry issues?

ED-057 wrote: 2) You can try sticking the caps in there, there's no harm in experimenting with different values. Is the bleeding only a problem when using the RGB input?

75Ω is the characteristic impedance of the cable. (I was taught what this meant. I'm not sure if I understood at the time, but I'm sure that I don't now...)

Bleeding is only an issue with RGB inputs, not composite or S-video. As for just sticking any 'ol capacitor. What is the recommended capacitance? 220μF that outputs 6.3V?

Capacitors are dangerous if I don't know what I'm doing! Has anyone here used capacitors on their RGB cables?

thchardcore · Post by **thchardcore** » Sun Sep 28, 2008 10:08 am

I owned one of these a bit ago, plus version if I remember my set had the exact same problem plus there was horrible issues with white black contrast, there is a word that eludes me for that type of behavior.

mrkotfw · Post by **mrkotfw** » Sun Sep 28, 2008 7:30 pm

thchardcore wrote:I owned one of these a bit ago, plus version if I remember my set had the exact same problem plus there was horrible issues with white black contrast, there is a word that eludes me for that type of behavior.

Did you ever find a solution to the problem?

ED-057 · Post by **ED-057** » Mon Sep 29, 2008 5:51 am

Piratero wrote:Will the XM29 manual tell me how to fix geometry issues?

Couldn't tell you. It sounds like this is a monitor with on-screen controls and stuff, yes? There might be something in there. But I was thinking potentiometers inside the unit.

Bleeding is only an issue with RGB inputs, not composite or S-video. As for just sticking any 'ol capacitor. What is the recommended capacitance? 220μF that outputs 6.3V?

Capacitors are dangerous if I don't know what I'm doing! Has anyone here used capacitors on their RGB cables?

If the plan here is to connect the capacitors in series with the signals to remove a DC offset then 220uF should do the job, and anything more than that would be equally suitable. Something as small as .1uF would bugger up the picture though. Voltage ratings on capacitors are just an upper limit, and the RGB signals are normally no more than 2V.

mrkotfw · Post by **mrkotfw** » Mon Sep 29, 2008 8:07 pm

Then 220μF 6.3V it is then!

Connect them in a series?

Code: Select all

R ---||--- SATURN R
G ---||--- SATURN G
B ---||--- SATURN B

ED-057 · Post by **ED-057** » Tue Sep 30, 2008 4:19 am

that's right