Need help with FDS ram adapter.

[Custom 8-bit]

Hey guys, I recently joined this forum in hopes that someone can point me in a good direction. I recently got a disk system but, was sad to find the graphics were garbled on every game.  First I tried cleaning the contacts on the ram adapter and that didn't help.  Then I checked for broken solder joints on the board... and for good measure "touched up" the solder at every connection.  When this didn't work, I checked for continuity on every circuit I could see and everything seemed to check out fine.  I then remembered reading somewhere that the Sony SRAM chips were causing some CHR graphical issues.  I replaced it with a Hyundai HY6264P-10LL.  This helped a lot, as now the background and words were perfect but, the animated characters still had a light distortion.  This is happening on all games I own.  So I repeated all of my previous steps and still can't find anything wrong.  For the hell of it I replaced the SRAM chip again with a known good Hitachi HM6264P-10.  This gave me the same result as the Hyundai chip.  In a last ditch effort I de-soldered the main connector  as there seemed to be a lot of flux or something built up and dark around those contacts.  I cleaned it off as well as I could and re-soldered the connector.  Still no change.  Is there anything I am overlooking or should I start shopping for a new ram adapter?  Thanks in advance for any input.   I have one picture of the glitch in SMB2.

[80sFREAK]

And with carts your famicom working fine, right?

[Custom 8-bit]

Yes, all of my standard Famicom carts work perfectly.
Post Merge: April 04, 2013, 06:18:50 am
Does the ram adapter access additional information on the Famicom console itself, that standard cartridges don't? 

[80sFREAK]

RAM adaptor working as any other cart, which have CHR RAM, IRQ and sound extension(this is not an issue in your case).

[famifan]

dram issues?

your ram adapter comes with a couple of discrete 1bit dram chips? or custom single one?

[Custom 8-bit]

dram issues?

your ram adapter comes with a couple of discrete 1bit dram chips? or custom single one?

I was thinking this could be a possibility.  I want to say my board has four or five slots labeled DRAM.  I was going to play with it some more after work today and see if I could come up with something. 

[sconley666]

curious how this turned out

[Custom 8-bit]

curious how this turned out

This is still a work in progress.  I currently suspect a problem with DRAM.  The first ram adapter I got has the 4 smaller chips.  I have since purchased another one.  The second one I got still has a minor glitch in the same area of the sprites, it is just not as bad.  For giggles I replaced the SRAM on the 2nd adapter as well, with no change.  I also noticed my 2nd adapter has the single large DRAM chip.  I have tested both on my standard, unmodified, Famicom, as well as, my NES/Famicom hybrid.  They have the same result.  I have a 3rd ram adapter coming from Japan as we speak.  Hopefully the 3rd time is a charm.  If this next one has the same issue I either have: really bad luck, 2 faulty consoles or a bunch of crappy broken ram adapters.

[Custom 8-bit]

Well, I received my 3rd ram adapter today and finally, I have one that works perfectly.  Now that I know I have two duds I will play with them to see if I can figure out the problem.  I still suspect DRAM but we will see.

[Custom 8-bit]

Well... the never ending quest to have a working disk system continues.  After playing on the third unit for about 30 minutes it started gliching in a similar manner to the previous two.  However the title screen works perfectly there is only a glitch while playing the game.  I have tried all the disks that I own.  I even opened.  A factory sealed disk with the same results.  So I replaced SRAM chip with no change.  I then socketed all 4 slots for the small DRAM chips and was making head way checking one at a time and viewing graphics changes by doing so.  Anyways now everything works well but the games will not load.  No disk load errors it just goes to a black screen when the game title screen should load.  It may be the sockets not getting enough contact but it was working this way previously.  I don't know, I'm about fed up with this thing and have way too much time and money wrapped up in it.  If anyone has any other suggestions I'd greatly appreciate it.

[80sFREAK]

Be sure, that you didn't damaged vias while desoldering DRAM.
Be sure, that you didn't killed anything with overheating or ESD.
Check voltage on DRAM.
Check power supply include noise on power rails close to DRAM.

[ringl]

If you do fix the ram adapter to not be grey screen

I am interested to see if you could fix the glitch.

I have 2 ram adapaters both with the exact same graphics glitch as you have.

They both have 4 dram chips too.

what make are your dram chips? My faulty ram adapters use Fujitsu memory, my working ram adapter also has 4 chips but they are mitsubishi

[Darth Kun]

Hi
I'm newly join with this forum
I have same video glitch symptom with my twin famicom AN 505
Which Cart mode is perfectly works fine but at disk mode booting screen there are terrible glitch and flickering display.

Could someone advise...which capacitor represent Ram Adapter should i change?
Thank you...

[fredJ]

Well... the never ending quest to have a working disk system continues.  After playing on the third unit for about 30 minutes it started gliching in a similar manner to the previous two.  However the title screen works perfectly there is only a glitch while playing the game.  I have tried all the disks that I own.  I even opened.  A factory sealed disk with the same results.  So I replaced SRAM chip with no change.  I then socketed all 4 slots for the small DRAM chips and was making head way checking one at a time and viewing graphics changes by doing so.  Anyways now everything works well but the games will not load.  No disk load errors it just goes to a black screen when the game title screen should load.  It may be the sockets not getting enough contact but it was working this way previously.  I don't know, I'm about fed up with this thing and have way too much time and money wrapped up in it.  If anyone has any other suggestions I'd greatly appreciate it.

Strange how this seem to happen with all of your RAM adapters. I have not had this problem with any RAM adapter.
Maybe the problem is somehow caused by your famicom, or the AV mod of it.

[Darth Kun]

Hi
I'm newly join with this forum
I have same video glitch symptom with my twin famicom AN 505
Which Cart mode is perfectly works fine but at disk mode booting screen there are terrible glitch and flickering display.

Could someone advise...which capacitor represent Ram Adapter should i change?
Thank you...

Bump...someone please help...