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RocknRollMcDonalds
July 27th, 2009, 02:25 PM
I have recently received a Sega Cd model 1 without the power adapter. I used a model 1 Genesis adapter for it with my model 2 Genesis on top but the Sega Cd won't power on. I opened the Sega Cd and tested the green fuse that has been a problem with most people but I still get a current from it. I also cleaned the port that connects to the Sega but that still does not solve the problem. I am using wrong adapter or need to look into root of the problem?

NathanAllan
July 27th, 2009, 07:38 PM
Hi, and welcome to the boards, you'll like it here. No onto the subject...

Both the Sega CD and the genesis on top need to have power supplies, you did know right? One does not bypass the other. After that, see what you get.

Also, make sure that the Genesis power jack does not wiggle around, the solder points are very prone to fail, there are only four little points holding it on (iirc) and they break easily.

Does the Genesis power up independently of the CD?? Do you have the right power supply for it?

cosam
July 28th, 2009, 12:49 AM
I'm pretty sure the original Genesis adapter should work on the original Sega CD. Have a look on the bottom of the unit for a sticker with the power requirements and check what your adapter is putting out. It's probably 10V 1.2A, but there are similar-looking adapters that are only rated 850mA.

Raven
July 28th, 2009, 11:33 AM
I am able to confirm 100% that the Genesis adapter will work on the Sega CD unit. I have a setup of my own with a Model 1 Genesis, Model 1 CD, and a 32x (I actually had the Genesis and CD since the 90s when they were much newer xD). I haven't used the CD unit in a long time, but it definitely works with ordinary Genesis power adapters.

My Genesis model 2 was rescued from a year-round outdoor flea market, where it likely got pwnt by quite a bit of rain and stagnant water. It looks like I got to it in time, but I still haven't powered it on, so I can't say whether it should work with the model 1 CD unit.

Last I checked my CD didn't want to turn on either though - I've got to troubleshoot that some time.

RocknRollMcDonalds
July 28th, 2009, 12:25 PM
Hi, and welcome to the boards, you'll like it here. No onto the subject...

Both the Sega CD and the genesis on top need to have power supplies, you did know right? One does not bypass the other. After that, see what you get.

Also, make sure that the Genesis power jack does not wiggle around, the solder points are very prone to fail, there are only four little points holding it on (iirc) and they break easily.

Does the Genesis power up independently of the CD?? Do you have the right power supply for it?

I know that you need power supplies for both Segas. I know the Genesis power adapter works since I use it for my Sega Genesis model 1, I am just using the model 2 Genesis on top since I have only one model 1 adapter. (I rather use the first model Genesis to play it since it does not glitch when I play games like Mortal Kombat as my model 2.

RocknRollMcDonalds
August 3rd, 2009, 03:58 PM
How about the little black fuse thing behind the power jack port? I haven't been able to get a read out of it, if this is the problem, can I replace it?

NathanAllan
August 3rd, 2009, 04:58 PM
If it's marked F1 on the board and it does NOT let current through, that's the next thing to check. Just for continuity with a multimeter, nothing fancy. It's a fuse.

RocknRollMcDonalds
August 5th, 2009, 05:11 PM
is it possible if the fuse is letting a current through but not enough to power the Sega CD? I know this question seem dumb but I am not that familiar with electronic repair and now what I thought to be a simple repair is becoming more confusing.

Another dumb question, I there also a way to test the current without having the Sega Genesis plugged in? Sorry I been putting up all these questions, I am that desperate to play Snatcher before I head to college.

NathanAllan
August 5th, 2009, 06:46 PM
When a fuse goes, it goes all the way as far as I know. It doesn't let anything through after that.

If you replace the fuse with original equipment, then if it goes again it will have to be replaced the same way again. While having a die-hard attitude having OEM is good sometimes (the world needs purists), a fuse in a holder is easier to replace when it has to be replaced again.

You can TEST it with just a wire and a known good power supply.

About testing current when it's not plugged in, not that I know of. It's late for me, been a long day so I might be missing something totally. Someone will correct me (Please!)

Nathan

cosam
August 6th, 2009, 12:23 AM
is it possible if the fuse is letting a current through but not enough to power the Sega CD?
Nope. Try looking at it the other way: the Sega CD is drawing current from the power supply, through the fuse. If it draws more than the fuse will allow, the fuse blows and nothing passes. If the fuse had somehow "partially" blown, it would be able to pass even less current than before and would blow completely the very next time the thing was switched on.


You can TEST it with just a wire and a known good power supply.
I'd avoid doing that in this case. If the fuse has actually blown, it probably blew for a reason, i.e. due to a fault further down the line. A bit of wire will generally allow a lot more current through than a fuse so, if there is something wrong, you could end up frying the thing with this excess current.

What you could use is proper fuse wire, rated the same as the original fuse. If you replace the fuse and it just blows again, you need to find out why it's blowing.


About testing current when it's not plugged in, not that I know of. It's late for me, been a long day so I might be missing something totally. Someone will correct me (Please!)
It'd certainly be difficult to measure current when there's no current present ;-) You can measure the resistance and, if you know the voltage, use Ohm's law (http://en.wikipedia.org/wiki/Ohm%27s_law) to calculate what current would be flowing if power was applied. For a fuse, however, you just need to test for continuity: it's either blown or it's not.

RocknRollMcDonalds
August 14th, 2009, 03:58 PM
Sorry I haven't replied recently, I have been preoccupied with others stuff. I think now I have found was is wrong. Under the metal shield of the side lighted panels, I have not received a read of a black tube that says "TB 17". Could that be the blown fuse? If so, what type is need to replace it?

NathanAllan
August 14th, 2009, 04:26 PM
I don't recall what that thing is, but that's not the fuse. It's marked F1 very near the power jack. Were you able to see my picture?

RocknRollMcDonalds
August 14th, 2009, 05:08 PM
I know where the F1 fuse is but when I test it I get a reading. I just don't know where the problems lies.

There could be another problem that I refused to believe. When I got the Sega CD, there was a sticker from a video rental place (I hope it was only for store use only). From what I read from this website http://www.digitpress.com/forum/archive/index.php/t-6080.html,
the connector pins could been worn down, but when I power the attached Genesis, power flowed from the fuse. I clean the pins very well but I am going to give it another shot, then I may have to rip into the Sega CD deeper to figure out the problem.