Magnvox Odyssey 2 White and Grey Screen Problem

[thegamezmaster]

Whenever I try to get mine to work, it only shows a white screen with squares and line grey colored like a maze. Anyone ever have this happen to theirs? Tried to search the web but no help. Can someone please offer some help? Thanks.

[thegamezmaster]

Can someone at least get me started in the right direction to fix, please!

[thegamezmaster]

Has anyone ever fixed one? What was wrong? Thanks!

[thegamezmaster]

Please can someone offer some advice or help? Need to get working as it's CIB with all the paperwork. Thanks!

[FABombjoy]

Have you cleaned the cartridge port and verified that no pins are bent / broken?

If so, the next thing I'd do is check for clean, ripple-free power at the CPU's (IC7) pin 40.

[Guy767]

I don't want to be Captain Obvious but like FABombjoy said; have you tried thoroughly cleaning the cartridge port?

If you want to do it gently then liberally spray a cart's contacts with CRC Contact Cleaner and insert the cart over and over again to clean the cartridge port. If you want to get fancy and expensive use Deoxit Contact Cleaner instead. However if using Deoxit then I would repeat the procedure with 91% Isopropyl alcohol to remove any lubricating residue that Deoxit might leave behind; it actually can prevent cartridges from reading properly.

If that doesn't work then you can try using fine grit sandpaper wrapped around a plastic card to remove corrosion. It's somewhat risky though as you can damage the contacts if you are not careful; only do so as a last resort.

I think the Odyssey 2 uses the same power adapter as a Sega Master System and Genesis. Try using a different power supply with a 9v DC + @ - (positive outer, negative inside) Don't use a NES Power Supply though as it is AC; it will fry most consoles. I learned this the hard way :beaten:

[FABombjoy]

Before considering sandpaper, try a stack of business cards or piece of thick posterboard cut to fit. Use these things dry, and run them in and out until the paper is no longer turning dark. Business cards are the trick used to clean solid-state pinball switch contacts and it works really well.

I avoid sandpaper whenever possible as you can cut through the platings that are either non-oxidizing (gold) or self-passivating (like tin). If you end up exposing more reactive metals, it's not a deal breaker, but it ends up being more maintenance down the road.

Odyssey2 is actually one of the rare AC-input systems, so an NES power supply would be fine. It's the same physical size as the Genesis / SMS so those power supplies are safe to use as well. It'll take just about anything from 9-12v as long as the connector fits.

[Guy767]

That's a great tip about using business cards/posterboard to clean contacts; thanks. I actually used a similar technique to clean the contact points on my Colecovision controllers. I just wedged some thin cardboard between the contact points, applied some pressure and slowly pulled out the cardboard a few times; it worked great.

Avoiding sandpaper is a good tip as well and I only use it as a last resort. It might work if you are really desperate and out of ideas though. Heck, I've even used steel wool to get a stubborn NES cart to function in the past and amazingly it worked. The contacts are not going to win any beauty contests any time soon though...

I didn’t know about the Odyssey 2 accepting AC either. The dastardly NES power supply has ruined more than one console for me in my youth so I've learned to fear and despise it! LOL

[FABombjoy]

I didn’t know about the Odyssey 2 accepting AC either. The dastardly NES power supply has ruined more than one console for me in my youth so I've learned to fear and despise it! LOL
Haha, that fear is 100% founded. I understand completely.. I almost killed a TG16 with a NES power supply years ago.

The Intellivision 2 also uses AC but the plug is a different size. There are probably a couple of others but the NES might be the last console to use AC.

[ApolloBoy]

There are probably a couple of others but the NES might be the last console to use AC.
The PAL SNES also uses an AC PSU, which it uses to make 5V DC and 12V DC, the latter of which is used for SCART autoswitching.

[thegamezmaster]

Have you cleaned the cartridge port and verified that no pins are bent / broken?

If so, the next thing I'd do is check for clean, ripple-free power at the CPU's (IC7) pin 40.

Cleaned the cartridge port and carts several times. No bent pins. Don't have an oscilloscope to check pin 40 of CPU for ripples. What should voltage be? Thanks everyone who has offered help, much appreciated!

[FABombjoy]

Don't have an oscilloscope to check pin 40 of CPU for ripples. What should voltage be?
Connect your VOM to CPU pin 40 and ground. DC mode should show +5v, AC mode should show a very small number.

[thegamezmaster]

Thanks, I'll try that. What if there's no 5 volts?

[FABombjoy]

If you have a picture on your TV, you probably have 5-ish volts. Likewise, if there isn't a buzz from the audio and/or a rolling bar in the picture then you probably don't have rectifier problems. If you have way less than 5v then you may have a regulator problem. I'd still suspect something physical like a damaged cart connector solder joint, but these are easy checks to make sure the power is good.

[thegamezmaster]

If you have a picture on your TV, you probably have 5-ish volts. Likewise, if there isn't a buzz from the audio and/or a rolling bar in the picture then you probably don't have rectifier problems. If you have way less than 5v then you may have a regulator problem. I'd still suspect something physical like a damaged cart connector solder joint, but these are easy checks to make sure the power is good.

Thanks for the help. I'll check it out and post results.

[thegamezmaster]

If you have a picture on your TV, you probably have 5-ish volts. Likewise, if there isn't a buzz from the audio and/or a rolling bar in the picture then you probably don't have rectifier problems. If you have way less than 5v then you may have a regulator problem. I'd still suspect something physical like a damaged cart connector solder joint, but these are easy checks to make sure the power is good.

Measured the power supply and output is 12.7 VAC. Measured pin 40 of IC7 and it read 4.80 VDC. So I measured the output of the regulator and it read 4.85 VDC. So I'm not sure if it's the power supply not putting out enough or the regulator. Do have another ps rated at 11.5 VAC 400mh and measured it and it's output is a little over 13 VAC. Not sure if the 4.8 VDC is the problem or not.

[FABombjoy]

Are you using an Odyssey2 power adapter? If you have an NES power supply, try it.

4.8v is getting low. What does the regulator input measure? Do any of the chips get hot after running for a minute or two?

[thegamezmaster]

I am using a Magnavox ps. Input to the regulator is 11.5 V. What rating ps should I use? Have to check the chips. Thanks.

[thegamezmaster]

Tried different power supplies, same results. Pin 40 and regulator still putting out 4.8VDC. Bad regulator? What regulator do I need if that's it? Can't read off part. Thanks.

[FABombjoy]

It's a standard 7805 regulator. 4.8v is still pretty close to spec. I doubt it's a regulator issue.

At this point I'd reflow the cartridge port solder and see if that does it.

For some reason the CPU isn't starting or operating correctly. This can be due to a variety of factors, including problems with:

-Damaged trace / connection to cartridge ROM
-Defective TTL chip
-System clock
-RESET line
-Bad RAM / CPU

[thegamezmaster]

It's a standard 7805 regulator. 4.8v is still pretty close to spec. I doubt it's a regulator issue.

At this point I'd reflow the cartridge port solder and see if that does it.

For some reason the CPU isn't starting or operating correctly. This can be due to a variety of factors, including problems with:

-Damaged trace / connection to cartridge ROM
-Defective TTL chip
-System clock
-RESET line
-Bad RAM / CPU


Thanks for the reply and suggestions. None of the IC's were getting warm or hot. Just the heat sink on the regulator. Not sure about the regulator as couldn't reach down enough. I'll reflow the cartridge port and post results. Again thanks.

[thegamezmaster]

Resoldered the cart connector and no difference. At this point I'm stumped. :roll:

[Niku-Sama]

you happen to have a flat bed scanner to scan the bottom side of the PCB?

kind of an odd but effective way to check traces and solder joints because the scanners see what ever it scans as being HUGE and so its pretty distortion free.
also you can post the pics and see if any one else sees any thing

[gustavotpd]

you happen to have a flat bed scanner to scan the bottom side of the PCB?

kind of an odd but effective way to check traces and solder joints because the scanners see what ever it scans as being HUGE and so its pretty distortion free.
also you can post the pics and see if any one else sees any thing

I have the same problem with my odyssey 2, any update?

I clean the port and cartridge, but have no success.