Lynx Backlight mod progress.

[Genki]

I've reviewed the schematic. It seems slightly different than the Lynx I have. (Perhaps it's because the schems is for the original Lynx and I am using Lynx II? ) but it looks easy enough ti disable/remove the high voltage driver without affecting the LCD itself. Next would be to make sure the white LEDs can be bright enough to work with out without the milky white plate found behind the LCD module.

 

Also anyone want a pic of the striiped down Lynx 2? Playing a game while the bare LCD was held to a lamp was a bit strange.

[Genki]

Anyone want to wish me luck? The next time I post here the stock CCFT bulb would no longer be plugged in. And I would have a few holes drilled in. I'll have to pick up a new drill bits as I can find my @$#@# old one that are just right for standard T-3/4 LEDs.

 

It does seems just a few white LEDs would be needed but not a lot. I don't know if I should install brightness control.

 

*edited* damn computer had hiccups and send 4 identical posts before I was finished*

 

A word of warning, if you have anything using CCFT open (ie Game Gear and TurboExpress) do avoid touching the little transformer where the bulbs are connected to. I just found out what 60v AC jolt feels like. Not as bad as the 120v AC or even the anode from the flyback but enough to make you jump and/or drop the extremely fragil bulb tube.

 

[ 10-19-2001: Message edited by: wi1ykat ]

[slimy007]

Good Luck!!! This sounds cool If it works. Also is it dose you just made the best handheld better.

[Albert]

I look forward to hearing how you fare with this mod. It'd be great to have a Lynx that runs for more than a few hours on batteries. Is it possible to determine what percentage of the power is being used by the existing backlight? If so, that might be a good way to determine what kind of battery life increase to expect once you swap the backlight for LEDs.

 

If it works, I hope you can take some pictures of the mod and write up directions that others might follow.

 

..Al

[Genki]

I just checked with my handy meter and hooked it up through an external battery pack. With the backlight on, it was drawing a total of 287 mA. When the backlight is turned off (only on Lynx 2) the current drops to 75 mA. A difference of 200mA. Of course if I wind up using 10 white LEDs or more, it wouldn't do any good.

 

Still haven't drilled yet.

[Genki]

Ok I goofed and blew out the original bulb. Wouldn't matter as I had a spare, a 150mm by 3mm that I salvaged out of my dead Mac Duo 230.

 

I won'tr be able to get the current down to 75 in normal use because the LCD itself is also off. I didn't check that so, with the LCD on but without the CCFT I'm drawing only 120mA. Still more than 150mA less than with the bulb.

 

I have already removed the bulbs from the reflector plate. I had o desolder both end of the bulbs and the 2 themistor fuses just to remove it all. Those fuses didn't survive the heat of my soldering iron anyhow.

 

I can probably tie in the backlight switch of the Lynx 2 with the LEDs so the LEDs would be off. (not applicable to Lynx 1, will someone please send me a working Lynx 1 damnit! Doesn't need to have working backlight, just that it works otherwise.)

[Genki]

Another problem. I installed 4 white LEDs and tested the whole LCD assembly. I was able to see the screen but... there's also some really bright spots as well. I did make sure the white diffuser plate is behind the LCD but the LED are too bright. I shouldn't have aimed those LEDs directly at the LCD. I'll have to do about face and make those LEDs aim toward the reflector plate.

 

At least I know it can be done and at about 100ma less than original design, that'd add about 2 hours to a standard 6 "AA" batteries. Or another year or 2 on those huge "D" packs.

 

Still waiting for a [cough]free[cough] Lynx 1 system to try out.

[Albert]

Thanks for keeping us abreast of your developments, I'm really encouraged by the fact you were able to drop power usage by 100mA. Hope you're able to get uniform lighting across the screen. I didn't think about this until just now, but would it actually be possible to replace the LCD screen in the Lynx with another screen that has a higher refresh rate? It would be awesome to have a Lynx that used a modern, backlit display.

 

quote

Still waiting for a [cough]free[cough] Lynx 1 system to try out.

 

I have at least four non-working Lynx 1 systems, I could send you one or more of them if you'd like to take a shot at repairing them. I don't know what's wrong with them, I believe they were demo units in POP displays (I only recently acquired them and I haven't had a chance to look at them yet). I'm sure whatever is wrong with them would be relatively easy to fix for someone who knows what they're doing.

 

..Al

[Genki]

A quick update. I have uploaded my pictures and a summary of this to my web site at portable.0catch.com

 

And to answer about using different LCD, it might be difficult as the stock LCD are tied into Mikey chip. There is no specific video (composite, separate, or RGB) that I can find. The replacement LCD would have to have the same row and column lines and uses same or similiar resolution. If it was a Nomad, I could do it easily as Nomad has composite line and I could have easily plugged in a 6" LCD.

 

[ 10-22-2001: Message edited by: wi1ykat ]