Sega Nomad internal rechargeable battery mod

[Elder]

Thanks Elder, glad to hear you're enjoying the gamegear.

I'll be doing a video of it in the coming weeks, so don't be surprised if a few people hit up your site and ask for additional info   It deserves to be seen by the world!!! haha.  Seriously though, I want to show people just how awesome this thing is.

[pdiggitydogg]

I'm getting about 3hr 40mins run time.  Charging time is a lot longer, i can you tell it's over 4 hours (went to bed before it finished charging).

pdiggitydogg, yes, I separated ground and positive of the ac jack from main mother board and wired them to step down convertor.  The low battery led on the nomad doesn't blink on low battery with this mod.  It stays lid.

Also, I had wired my setup (since I was basically using just the batteries and all of my safeties were external) directly to the factory battery prong locations (removed the prongs).  The battery light still worked correctly when done this way.  However, there was not a ton of warning.  I think I would only get maybe 60-90 seconds more usage after the light would come on.  Just enough to hopefully save your game if you were playing Beyond Oasis or something like that.

By connecting the lipo set to the oe battery points, internally, does it still charge with the original jack/adapter? Can you use the AC for power when the batteries are flat?

[Desh]

I'm getting about 3hr 40mins run time.  Charging time is a lot longer, i can you tell it's over 4 hours (went to bed before it finished charging).

pdiggitydogg, yes, I separated ground and positive of the ac jack from main mother board and wired them to step down convertor.  The low battery led on the nomad doesn't blink on low battery with this mod.  It stays lid.

Also, I had wired my setup (since I was basically using just the batteries and all of my safeties were external) directly to the factory battery prong locations (removed the prongs).  The battery light still worked correctly when done this way.  However, there was not a ton of warning.  I think I would only get maybe 60-90 seconds more usage after the light would come on.  Just enough to hopefully save your game if you were playing Beyond Oasis or something like that.

By connecting the lipo set to the oe battery points, internally, does it still charge with the original jack/adapter? Can you use the AC for power when the batteries are flat?

That was the major drawback to my setup.  The A/C port became the charging port (the A/C port was no longer connected in it's original location but rather wired directly to the battery packs).  Since, all of my charging protection occurred in the extern charging unit you could not play while the batteries were charging.  You also did not have a way to use a wall adapter if the batteries were dead.

This was one of the major issues I hoped I could change in the future.  I think turbokon is on the right path with his setup.  I think I should use his ideas but change the charging circuit up a bit

[pdiggitydogg]

I'm getting about 3hr 40mins run time.  Charging time is a lot longer, i can you tell it's over 4 hours (went to bed before it finished charging).

pdiggitydogg, yes, I separated ground and positive of the ac jack from main mother board and wired them to step down convertor.  The low battery led on the nomad doesn't blink on low battery with this mod.  It stays lid.

Also, I had wired my setup (since I was basically using just the batteries and all of my safeties were external) directly to the factory battery prong locations (removed the prongs).  The battery light still worked correctly when done this way.  However, there was not a ton of warning.  I think I would only get maybe 60-90 seconds more usage after the light would come on.  Just enough to hopefully save your game if you were playing Beyond Oasis or something like that.

By connecting the lipo set to the oe battery points, internally, does it still charge with the original jack/adapter? Can you use the AC for power when the batteries are flat?

That was the major drawback to my setup.  The A/C port became the charging port (the A/C port was no longer connected in it's original location but rather wired directly to the battery packs).  Since, all of my charging protection occurred in the extern charging unit you could not play while the batteries were charging.  You also did not have a way to use a wall adapter if the batteries were dead.

This was one of the major issues I hoped I could change in the future.  I think turbokon is on the right path with his setup.  I think I should use his ideas but change the charging circuit up a bit

This is my hangup.
I want the jack to still power the unit if/when I want it to, in addition to changing the batteries. Is this a relay issue?
It's probably something I am just not understanding as a real modding novice.

[turbokon]

You can add a switch to toggle between charging and powering up the nomad.

[pdiggitydogg]

That would be the simplest thing to do, yeah. I am over complicating it trying to shoehorn in ideas of 5v relays and whatnot...