Welcome, Guest. Please login or register.
Did you miss your activation email?
August 24, 2019, 03:30:25 AM
Home Famicom World Search Calendar Login Register

+  Famicom World
|-+  Family Computer
| |-+  Technical & Repair Assistance (Moderators: manuel, L___E___T)
| | |-+  Capacitor question
0 Members and 1 Guest are viewing this topic. « previous next »
Pages: [1] Print
Author Topic: Capacitor question  (Read 4299 times)
Raverrevolution
Disk System
***
Posts: 222


« on: December 06, 2016, 05:07:27 PM »

So recently I installed a Hi Def NES mod into my Famicom AV and all is good. 

I noticed that however that cap C5 which is rated at 220uf 6.3V really got in the way of one of the ribbon cables.  So I figured I'd just replace it and lay the next cap down flat and bend the legs.

I stopped over at Radio Shack and the closest cap I could find was 220uf 35V.  Despite it being a tad bigger in size I was able to solder it in the way I wanted to perfectly and at last it didn't get in the way of any components.

I then tested everything out and all seems to work well on both HDMI and AV

So my question is that if this was okay to do.  I am under the impression that the voltage rating is more so how much the cap can handle and that the uf rating is the more important number to match up hence I grabbed this one.

Secondly what component is cap C5 for?  On Gametech's youtube video on the Famicom AV install I seem to hear him say that the cap can be replaced for AV.  Is that specific to just the AV of the console?
Logged
famifan
Twin Famicom
*****
Russian Federation Russian Federation
Posts: 934



« Reply #1 on: December 06, 2016, 07:02:42 PM »

yes, it's absolutely fine.

moreover, you haven't had to find the exact 200uF cap for a replacement. as you may know, those electrolytic capacitors has a relatively big tolerance of capacitance. For the most of the caps it's in 10-20% ballpark. it's even drifting around under different operating conditions about 10% at the very least. just deal with it, it's not a precise piece of capacitance.

actually, in real world, nobody cares about the capacitance that much, especially when it's time to use electrolytic caps. so, any scheme with the use of electrolytic caps is designed to overcome the inaccuracy in capacitance. A rule of thumb is that the capacitance shouldn't be bigger or lesser than 2 times of the required value.

if the scheme requires 220uF electrolytic cap, it literally means that anything within 100uF and 400uF will work just perfectly fine. The scheme is ready to deal with that.

higher voltage rating won't be harmful anyway. It's just bigger in size and more expensive than 6.3V. Sometimes, 6.3V is quite enough and there's no much room to fit anything bigger.

regarding your second question it's quite hard to answer without pic/scheme.
Logged
Raverrevolution
Disk System
***
Posts: 222


« Reply #2 on: December 06, 2016, 07:26:01 PM »

Ah awesome!!    Grin  Thanks for the help!  Much appreciated.

Taking out the CPU and PPU on this thing was like performing heart surgery.

I'm attaching a general pic of the motherboard with the cap in question circled.  It's the same one I mentioned above that I replaced.  I was just curious what specifically it's for inside the whole thing.  I'd look through schematics, but I have no clue what I'm reading.

I figured if the cap was specific to the AV function of the motherboard then regardless of what's soldered in, keeping to the specs, it shouldn't be too bad, because when the HD takes over the AV is disabled.
« Last Edit: December 08, 2016, 11:35:54 PM by Raverrevolution » Logged
Pages: [1] Print 
« previous next »
Jump to:  


Powered by MySQL Powered by PHP Powered by SMF 1.1.21 | SMF © 2015, Simple Machines Valid XHTML 1.0! Valid CSS!