About the interface unit...

[SegaCD]

Hey guys, I have an IFU and CD-ROM-ROM unit, but no PCE yet... I don't have the original AC adapter, but I took a recommendation for a 9V Radioshack one (with an adaptaplug "Q"). I'd like to see if this at least works before I move on to purchasing a PCE.

So my question is this: should the IFU's power light light up when I move the "power-lock" lever to the on position even when there is no PCE plugged in? Because on my unit its not lighting up and that is worrying me... The plug is pretty snug so I'm worried that the generic adaptaplug is not making complete contact either (even though the person in the other thread said it should work). I matched the polarity of the plug to the diagram on the bottom of the unit too...

[Samurai Ghost]

I don't have one on hand to check but you might need a PCE in there to complete the circuit.

[SignOfZeta]

It won't do jack unless there is a PCE installed.

[incrediblehark]

The IFU power led will light up when in the lock position, even without a pce or cdrom unit attached. My guess is either the polarity is wrong on the ac adapter, or the adapter isn't strong enough (uses 9v 1450mA) or something is blown in the IFU (fuse most likely)

[Frank_fjs]

+1 to the above. The power LED should still light up on the IFU even with no consoles connected.

[SegaCD]

Just what I was afraid of.

@incrediblehark Its a Radioshack 273-1771 AC adapter which is rated at 1.5A so it should work fine. I also tried flipping polarity on the plug but it did nothing.

Since I made that first post, I've opened the unit up and poked around inside with a voltmeter. I'm getting some weird 14v difference across the positive and negative wires leaving the AV-out/AC-in combo board when the switch is in the "lock/on" position and nothing when its off... Well at least the switch works! But is that potential difference normal? Lol... My voltmeter said that AC adapter itself is putting out a solid ~9v at the tip though.

Anyway, Is there a fuse on the IFU? If not, does anyone know of any resistors or caps I should check on the board that might be blown? I'm guessing someone plugged an incorrect AC adapter into this or something. Thanks Ebay!

[Samurai Ghost]

Well if it makes you feel any better loose IFUs can be had for a few bucks so if it's not something easy like a loose wire or fuse you could always keep an eye out for a cheap one. I might have a few spares. Had 10 or 12 of the things at one point...

[SegaCD]

Yeah I know...but this unit has the same serial as the CD-ROM unit so I'd like to keep them together if possible!
And also resurrecting a dead unit is just plain satisfying!

[Samurai Ghost]

Yeah I know...but this unit has the same serial as the CD-ROM unit so I'd like to keep them together if possible!
And also resurrecting a dead unit is just plain satisfying!

Agreed! Check the fuse as it might have been blown if someone plugged in the AC adapter with the wrong polarity.

[SegaCD]

Where is the fuse...?
I see a gigantor diode which seems to check out okay... Could that be it? If it is, then thats not the problem...  

EDIT: That 14V difference I'm talking to is now down to 5V. Makes more sense, but I don't know whats going on. haha

[Samurai Ghost]

Not sure where the fuse is as I've never had to replace one. If you are planning to get a PCE anyway I'd just try testing it with that one before tearing it apart.

[SegaCD]

*cough* *ahem* A little late now. Hahaha!
Well I'm trying to find a boxed PCE in decent shape for a decent price which is why I've been holding out... :/

@incrediblehark and Frank_fjs: Did you guys actually try this without a PCE even inserted into the IFU? I know the IFU is supposed to light when a PCE is plugged in but not turned on... But I'm following the traces on the main board from the incoming power and the negative seems to go directly to the PCE console connector in two different places and thats it. No other visible place. Maybe one of these just is a pass-thru for the power that goes through the console even when its not on. Before I delve deeper, can someone confirm that without a PCE in the IFU, the indicator on the IFU still lights? I know the question is sort of redundant, but I'm hitting a wall and I just need a complete confirmation.

[Samurai Ghost]

I wish I had my PCE stuff on hand so I can tell you, but I know the thing won't light up just because it's plugged in. At the very least you have to turn it on by lifting of that little bar/lever in the front and sliding it all the way to the right. I know it's obvious but just to rule that out. Can someone on here with an IFU handy pop their PCE out and see if it lights up with nothing plugged into it?

[SignOfZeta]

I just checked and the CDROM2 is fully operational with the PCE removed. I could have *sworn* it wasn't like that before...hmm...

FWIW; I have the later version that says "PC Engine" on the cover rather than "IFU-30".

[Samurai Ghost]

Well the CDROM2 should work if it gets power, so yeah that makes sense. You can plug the AC adapter into it directly and it will play audio CDs just fine. But obviously it won't play games without a PCE in there.