How "small" can I get them? I am gonna' give another go at hacking together a SNES RGB cable and I want to get some axial style caps with as low voltage as I can get (so they will be physically accommodating to my tiny DIN-6 connector) What caps do you all use, and where can I get them?
Also: Last time I tried to put a cable together I wasn't able to get a stable picture. Someone on these forums suggested I actually use a resistor between the o.2uf cap and the LM1881 sync-separator chip. I don't know if this is true because when I tested out my hacked-up cable, the DIN-6 connector wasn't fully assembled, it was just the pins that I plugged into my Commodore 1084 monitor without the housing. Could that be the reason I couldn't get a stable image and not the resistor?
Thanks for your time...and wish me luck.
Tantalum capacitors are as small as you get. Potentially, 220 uF units could be only three millimeters wide and tall. Problem is, Tantalum is really expensive now that they're using them in mobile phones. For lack of a better source, Radio Shack might still have older stock lying around in forgotten corners.
Probably a little difficult to work with, but you can certainly use SMD ceramics.
You should be able to solder to each end carefully with patience.
Well I guess I don't need them SUPER small, but just something I can work with that will fit into a smaller connector.
What do you guys personally use? Perhaps you could link me up?
I was thinking 220pF, don't know if you can even get 220uF ceramic caps, why the need for a 220uF cap for this?
Digi-Key carries 220uF Tantalums, but they're anywhere from $8-$13 a piece.
They are not exactly 'tiny' but the smallest 220uF electrolytic capacitors I have found are 'Sanyo 220uF 6.3V capacitors' which also happen to be the same as the ones used in official Nintendo scart cables. Theres some on eBay here:-
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=110287806133
According to the listing the dimensions are:-
* 6 mm diam X 7 mm length
* 20 mm & 22 mm lead lengths
Hope that helps :)
Thanks, Link83. Those would be the sorts of caps that would really work well for me. Although I would like to find those caps in axial style leads.
Here are some axial tantalum caps for less than $5 each.
http://www.alliedelec.com/Search/ProductDetail.aspx?SKU=5410410&MPN=T322E227K006AT&R=5410410&SEARCH=5410410&DESC=T322E227K006AT
If you need to jam three caps plus resistors into a 9-pin hood, you should try to get small caps. I just made a Genesis 1 RGB cable, and I can't get all of the junk to fit into the hood, so now I am going to have to figure something out. If I had smaller caps, this would be a non-issue.
Chris
I generally put all required things in the system itself...
Thanks Chris, but DAMN, those caps are expensive!! And I'd rather not open up the SNES itself to add more electrical components.
Thanks guys for all of your help, though.
Quote from: zedrein on April 12, 2009, 02:55:21 PM
Thanks, Link83. Those would be the sorts of caps that would really work well for me. Although I would like to find those caps in axial style leads.
Sorry, didnt notice you said axial.
Well they are not the same brand or type but I found these:-
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330319933890
Doesnt mention what size they are though, perhaps a quick email would confirm if they are small enough?
Quote from: Link83 on April 14, 2009, 12:14:35 AM
Quote from: zedrein on April 12, 2009, 02:55:21 PM
Thanks, Link83. Those would be the sorts of caps that would really work well for me. Although I would like to find those caps in axial style leads.
Sorry, didnt notice you said axial.
Well they are not the same brand or type but I found these:-
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330319933890
Doesnt mention what size they are though, perhaps a quick email would confirm if they are small enough?
I ordered these and they are are humongous. Oh well. I'm only out about $3.
Chris
I just got done reading some documents about RGB on the SNES/Super Famicom, and they said that you get blurriness while using caps. Is this just the sad truth of RGB on games consoles with using caps? Is there a way to eliminate the "blurriness' described?
don't use 220µF caps, use 100µF, or build your own RGB amp...
Quote from: Jibbajaba on April 21, 2009, 09:42:21 AM
Quote from: Link83 on April 14, 2009, 12:14:35 AM
Quote from: zedrein on April 12, 2009, 02:55:21 PM
Thanks, Link83. Those would be the sorts of caps that would really work well for me. Although I would like to find those caps in axial style leads.
Sorry, didnt notice you said axial.
Well they are not the same brand or type but I found these:-
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330319933890
Doesnt mention what size they are though, perhaps a quick email would confirm if they are small enough?
I ordered these and they are are humongous. Oh well. I'm only out about $3.
Chris
Sorry, was just trying to help :(
(I did suggest emailing first though to check the size)
Quote from: Tiido Priimägi on April 21, 2009, 08:43:14 PM
don't use 220µF caps, use 100µF, or build your own RGB amp...
100µF? Got it. I wonder why this site doesn't suggest using those instead knowing that 220µF caps can contribute to blurriness?
I'm actually using 47µF caps in my SNES... the blurring is quite unnoticable.
Quote from: Tiido Priimägi on April 23, 2009, 07:41:44 AM
I'm actually using 47µF caps in my SNES... the blurring is quite unnoticable.
That's what I'm talking about! I wonder why there is blurriness from caps in the first place?
Lawrence, can you explain why you recommend using 220µF capacitors when other alternatives can be better suited?
Quote from: zedrein on April 23, 2009, 08:26:51 AM
Quote from: Tiido Priimägi on April 23, 2009, 07:41:44 AM
I'm actually using 47µF caps in my SNES... the blurring is quite unnoticable.
That's what I'm talking about! I wonder why there is blurriness from caps in the first place?
Can you explain exactly what you mean by blurry?
Quote
Lawrence, can you explain why you recommend using 220µF capacitors when other alternatives can be better suited?
This capacitor is series with the video signal only serves to remove the DC offset. Anything less than 470u will distort the low frequency parts of the video signal. 220u is used most often because it's good enough... Sometimes I see 100u used in cheap SCART cables.
Try to experement with different sized caps.... you should start to notice the distortion from 47u and below. It would be most obvious picture with very little detail.
If you use really poor quality caps then they may be attenuating the higher frequencies... that's the only way I could think they might cause the picture to be blurry. Try putting a ceramic cap, something like 0.1u in parallel with the big electrolytic.
http://www.disgruntleddesigner.com/chrisc/gotRGB/screenshots.html
This gentleman, who conducted experiments with RGB vs. Composite video in several gaming consoles, says that, "A small amount of blurring is evident...this is probably unavoidable because the Super Famicom's RGB output requires caps inside of the connector which adds horizontal blurring to any image"
I am just trying to get the best information out there, and if I can get the least amount of signal degradation possible, I will be a happy camper.
Quote from: zedrein on April 23, 2009, 08:26:51 AMLawrence, can you explain why you recommend using 220µF capacitors when other alternatives can be better suited?
Because that's what Nintendo used in their first-party cables. If it's good enough for the people who made the SuperNES, it's good enough for me. =)
Interesting. Lawrence, would you care to comment on this "blurring" effect that's been described in the linked-article?
Quote from: zedrein on April 24, 2009, 03:07:15 AMInteresting. Lawrence, would you care to comment on this "blurring" effect that's been described in the linked-article?
Not much, really.
My own experience using 220uf caps suggests that there's no reason to use a different value - they work perfectly well. No noticable blurring was detected.
Interesting. The guy who wrote that post up must've been using cheap caps then.
Thanks for your input!
Horizontal blurring is more likely caused by capacitance in parallel with the line. This could be introduced by using excessively long, thin cable.
Quote from: viletim on April 25, 2009, 12:05:12 PM
Horizontal blurring is more likely caused by capacitance in parallel with the line. This could be introduced by using excessively long, thin cable.
*delivers a huge kiss to viletim* Thanks for clearing that up for me!