Technical and Repair Assistance

[UglyJoe]

Either buy a driver/bit with a skinnier shaft or give the pen method a try.

[malthusian]

I've a question I'd like to pose to all you accomplished Famicom nerds. I recently bought an AV Famicom. It arrived promptly (for having come from Osaka, anyway) and it worked fine. However, at the end of the first day, I was in the middle of a game of Dragon Quest II when it locked up. I now can't get it to read cartridges. Some maybe pertinent details:

I noticed that I had to apply a lot of pressure to the eject switch, particularly with the game that shipped with the console, the Bandai-released Saint Seiya tie-in Ougon Densetsu. Having never used a Famicom before, I'm not qualified to say is this normal or not. My other Famicom carts ejected with comparatively little effort. Compared to Ougon Densetsu, that is.

And also probably worth mentioning is that the adapter included in the package was not an offical adapter, in fact on the bottom of the box it lists it as being usable with both the SFC and the PCE. Although not official, it does seem to match up to all the relevant specs for an official adapter: AC100V 50/60Hz DC9v~10v850mA; quoting directly from the box.

I don't by any means understand what all of that signifies, but I do know it matches up more or less exactly to similar instances of electrospeak I've seen with regards to official Famicom adapters. I don't however believe that the issue is with the adapter although that may not be the case, and in fact I'm leaning towards discounting voltage issues in general because I think if I had 'fried' my console it would have A.) been more dramatic and B.) have precluded me getting a gray screen, which is what now happens when I insert a cartridge. Some sort of brief but dramatic summary of the process of 'frying' would probably be helpful to me. I should probably add that I live in the US and was not using a step-down converter, although I've read numerous reports of this being really not much of an issue juxtaposed with conflicting reports claiming it to be the central issue. So but I'm not sure what to believe there.

One last maybe important detail is that although the Famicom in question is equipped with A/V cables and therefore an AV Famicom, it is at the same time definitively not the gray-colored Famicom HVC-101 model. We're referring here to an original Famicom with the white-red-gold chromatic scheme and the irrevocably-attached controllers, much more compact than the bulky NES and more visually interesting than the HVC-101. The A/V cables share a port on the back of the device with the cord for the 2P controller. I don't know was it modified in this way at some point in it's life or what exactly the full extent of the deal is there, but I assume this could be important.

I was considering trying to clean the bit that reads the game cards (pins are they called?) with a toothbrush dipped in rubbing alcohol, which I've seen suggested for similar problems, but any other suggestions or advice any of you could provide would be most welcome.

[jpx72]

Accomplished Famicom nerds?

[malthusian]

It was a compliment.

[ericj]

My guess, if cleaning the cart connector doesn't help, is that a connection came loose in the AV mod. Any chance you'd be willing to open it up after cleaning & re-testing if it still doesn't work?

[jpx72]

What voltage do you have in the US electrical outlets? Because inserting a 100V adapter in 220V socket is really a bad idea..

[ericj]

110-120V for standard outlets, 240V for larger appliances like stoves, clothes dryers, etc. But, the outlets are shaped differently.  Even so, if you plugged a 110V appliance in 240V it'd blow right away, there'd be no playing it first. Also, you definitely wouldn't get a gray screen if the cap, ac adapter, and/or voltage regulator popped.

[jpx72]

then it's most likely that something from the AV mod is loose
Cartridge lever hardness is normal...

[malthusian]

I should also note that I plugged it into a power strip rather than directly into an outlet, which I think in itself dilutes the voltage somehow. I would be more than willing to open up the console although I've never really done it to anything I didn't want to break before. Would I be getting a gray screen if the cables had come loose? I'll try cleaning and report on results.

[jpx72]

If you won't be lucky by cleaning it, open it and post some photos. Our company of Accomplished Famicom nerds will take a look at it

[ericj]

The power strip makes no difference and doesn't change the voltage. The Famicom works on 5V via an internal 7805 voltage regulator anyways. As long as you're within the specs of the 7805, voltage should be fine.

Does the gray screen flash as you turn it on/off? If so, check your AV cables, clean the cart connector, and then open it up if it's still not working.

[jpx72]

Like ericj is writing, most likely it's just a bad connection between famicom and cartridge (if you see the gray screen after powering on). Clean also your cartridges.

[malthusian]

One Isopropyl rub-down later...

No change. Checked and cleaned housing and all cartridges. I'm gonna have to go inside. I'll do it carefully and post some photos. Plus and I'm getting a proper HVC-101 AV Famicom pretty soon, so that'll obviate the problem. Although I do like the original color scheme much better. I will return.

[Xious]

Alright...  A dirty cart slot wouldn't have caused the game to crash like this during operation: it would have caused the game to be unable to load initially, or caused graphical glitches, but this would've been readily apparent with DQ2. If you use rubbing alcohol be sure to use 91% concentration, not 70%. You can use a toothbrush, then use something like thin, sturdy cardboard around the thickness of the PCB edge of a cart to insert into the pins on your FC. The abrasiveness is helpful to clean the corrosion.

--{Is there still a good source for real cart cleaning kits; maybe genesis/MegaDrive, NOS or newly made?}--

When using a toothbrush, be aggressive, but gentile. Don't force it into the slot or bend the pins! Apply only a drop of rubbing alcohol to the brush; more than that will just leak into the system and spread moisture all over the place; be sure that after cleaning, you let it dry thoroughly. Don't blow it dry with either your moth, or a hair-drier! The vapours from your lungs will help to re-corrode the pins, and a hair-drier may damage the system. --{Yes, I've heard of people using the latter.}-- Let it sit out at least overnight, or pick up a mini-bellows (hand-bellows) from your local auto-repair or tools shoppe. They cost very little and are quite effective.

Honestly, I suspect this to be a power problem or a damaged modification. I have to ask, did you jar, or drop the system; maybe tug the controller too hard during use when this happened, or did it just occur out of the blue?

Depending on if the mod was done free-floating (bad) or on a PCB (good), there are a lot of things that could've happened. If the mod was done properly, then it's possible that the GND connection fell off. That would instantly kill both audio and video though. If +5V came loose, you'd get a bit of luminosity, (possibly a de-synced image) and sound.

Are you still getting sound, but with a grey screen? Did you buy it from a dealer in Osaka? if so, it may be guaranteed in some way...and if it is, then they may cover cost of repairs.

When taking photos, please be sure to locate the part number on the transistor that was used. If you need help with this, PM me or post here.  --{It's good to know if it's NPN or PNP and which poles are which (CBE, ECB, EBC, etc.) when looking at how the mod was done to be sure of where everything should connect.}--  I'll see if I can walk you through repairing it, should that be the case.

Is the original RF box still intact and functional? You can verify the system's operation via RF as well if it is, and this will tell you if the mod is to blame, but could take some doing, as Famicom units can be problematic to use on US TVs without some extra work.

It can be a power issue as well. I recall several instances that cause light grey screens: A blown fuse may have been one of them: I don't recall, but I can test for that later to see. Lastly, using the original PSU on 110-120VAC (North America) is a bad idea. That's as much as 20% beyond what the adapter is designed to convert, and this may and probably will cause heat issues, and will damage at least the power supply in the end. FYI, the PSU is the same for the Famicom and the Super-Famicom--all the way down to the part number. In fact, heat can cause the fuse to go, and if I'm right in my remembering, that may be the cause of this.

If you want to 'dilute' the voltage, you need a step-down transformer (110VAC-->100VAC) to do so; these are easily purchased and cost about US$60 and up, depending on the desired maximum load. You can also get a USA-spec'd PSU (110VAC->10VDC) that'll work perfectly.

[malthusian]

A further question: I'm looking for a voltage converter, but do I need a step-down converter or step-down transformer? I'm slightly confused with the whole thing. I live in the US, where I believe outlets output at 120v, and my impression is that I need to step down to 100v, so could somebody please tell me exactly what I should be getting?