Master System C2 (ceramic capacitor) value

Hello and thank you for checking this thread.

So a few days ago I bought a broken SEGA Master System (Motherboard Revision M4 PAL) off of eBay, and knowing that the System wasn't outputting any video or audio, and the power LED was lighting, I thought it would just be a simple voltage regulator replacement. so when it arrived, the first thing I did was check if it was outputting anything through RF to make sure the clock circuitry wasn't damaged, and sure enough, it was outputting a solid black screen. so I bought some new 7805 voltage regulators.

I had struggled removing the original voltage regulator and I believe I have damaged the capacitor C2 through applying too much heat, I also damaged most of the motherboard in the area while trying to remove the solder from the through holes on the PCB, as I had to solder a wire from the underside of the motherboard to the topside of the board just to get it the power LED to light up again, but now the console isn't outputting anything at all.

I've checked C1 with the continuity setting on my multi-meter and it still seems to work, but there was nothing coming from C2. I did attempt to replace C2 with a 104 (0.1uF) capacitor but that hasn't made any difference. I've also checked the new voltage regulator and it's outputting exactly 5V.

The original C2 capacitor has .IZ 25V printed on it.

So basically I'm asking if anyone knows the value of C2, and if anyone doesn't think that C2 is the problem, then could you please tell me the solution.

Thank you in advance

Here are some images of the system:

 

Oh my gosh it's ASSEMbler *Attempts to act calm and collected*

Thank you so much for replying.

So the rating of C2 is actually 0.1uF 16V, I checked the Master System service manual and it said the same. So I wonder why mine contains 25V caps.

Thank you so much again

 

C2 will have no bearing whatsoever on whether the console works or not, it can be completely removed and not effect its functionality, its simply across the input voltage to the regulator.

Why would you assume the regulator was bad if the consoles power light worked, and the RF was outputting a black screen?

 

Thank you for commenting

I reason being I've read on other forums that a damaged regulator (probably through using an NES power supply) can still output a voltage but it's only around 3V or so, that would only be enough to power the LED and the video controller, but not anything else.

So basically the console is beyond repair (although I would do anything within reason and my power to repair it), and I've just made it worse. I regret not testing the original voltage regulator now.

 

Because they're compatible. Voltage doesn't matter too much if you go over but under is bad. I could speculate on why there is a difference but likely it was something like the service manual was wrong, the schematics were wrong, someone needed to keep production going and these are compatible, etc.

 

Thank you everyone for your help.

I do actually have a working Master System II but as everyone knows, the video quality is terrible.

Is there a Capacitor I can salvage from another part of the motherboard as a test? and how do I wire up video out directly to the Video chip?

Thank you again.

 

here you go

 

Okay, thank you/

Unfortunately I don't have the parts for this mod at the moment (well at least I don't think so). would an RGB Megadrive cable work on a Master System to test it?

 

An RGB SCART MD model 1 cable will work as it uses the same 8-pin DIN connector. The model 2 cables will need a custom adapter.

 

Just a note, you cant test a capacitor with a continuity tester. Capacitors block dc signals

 

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Higher voltage only becomes a problem if physical size is a restriction. It's a maximum the component can handle, so more is better to an extent.

 

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Hello, Sorry I've been away for so long, I get easily detracted (damn Steam sales).

I've checked C1 with my continuity meter and there is a connection, could that be the problem?

I've also checked the Master system with two different RGB/AV cables and it still isn't outputting anything at all (the TV even says "No Video" just to prove it), and one of the cables (composite) definitely work as I've tested it on both my modded (region/language switches) and un-modded Model 1 Megadrives and it worked fine with both of them, I was also going to try a Megadrive Model 2 RF modulator, but I can only get bursts of static from that even with my Model 2 Megadrive (the thing doesn't work most of the time anyway).

My other cable which is a Megadrive model 2 RGB scart cable with a Model one converter with a Stereo 3.5mm Jack for audio, and with all both of my Megadrives, it only outputted audio and no video.

Thank you to everyone for your help.


Here's some images of the cables (in-case anyone wants to know):

The RGB cable I normally use (that now doesn't work for some reason:


A DIN composite cable I found laying around that worked:


The connectors of both cables:

 

*Sigh* I don't know what's happened, but I think the system is completely dead now.

I decided to take another look at the solder joints to check if everything was okay, and when I continuity tested the topside of the motherboard conncted to the output pin on the voltage regulator, there was quite a lot of resistance (sorry I can't remember what setting I had my mutimeter set to but the reading was 1.38), so I bridged thae top of the board to the bottom of the board, after that I was getting no resistance, so I checked for shortages and there weren't any, so I plugged the system in, and straight away I could smell something burning and the chips (especially the VDP) started getting really hot, so I unplugged it as fast as I could, gave it a minute or so, and plugged it in to test the regulator, and the regulator was outputting 9V. so something has happened to the voltage regulator and it's just sent 9V to all the chips. so I'm pretty sure the system is dead now.