game gear repair

Started by jetblue, December 06, 2008, 04:55:44 PM

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jetblue

howdy,i just finished doing a cap replacement for my game gear:
http://img.photobucket.com/albums/v238/jetbue7/gg1.jpg




but i get sound and picture but no backlite. After searching the web i found a thread over at segaxtreme:     http://forums.segaxtreme.net/showthread.php?t=30032&highlight=game+gear+back
thats says its a fuse/resistor on either side of the backlite. i checked the resistor thats labeled on the board as FU1 and FU2 with a multimeter and only FU2 seems broken.
I cant replace it cause its directly under the bulb and the bulb is soldered to the board.
Have any of you fixed that before? i thought of bridging it with a piece of wire or piggybacking another resistor over the broken one but i cant see the type of fuse or resistor all the way cause of the bulb and the black covering. Does anyone know what kind i should use?


Thanks for any info.

viletim

Unscrew the silver plastic reflector then heat up the solder joints on the fluoro tube and pull the wires out. The reflector and fluoro come out as one piece. Replace/jumper your fuse and put everything back.

BTW, you missed C4. Replace it with a 47µ if you can't find a 68µ.

jetblue

yeah i want to avoid touching the bulb all together if possible. even just moving the black rubber thingy i could hear it make strange noises. another forum suggested i cut the two ends of the fuse then slide it out from under the bulb but i need more info.


couldn't find a 68uf cap in none of my junk boards so i thought id leave it if it was still functioning. shows no sign of leakage or corrosion yet and looks good on the meter. But cool i can put a 47uf one in there. ill do that immediately.
Those smaller caps were harder to find but found out old telephones were a good source especially those with mini cassette answering machines in them.
thanks  :)

viletim

Quote from: jetblue on December 07, 2008, 03:00:08 AM
yeah i want to avoid touching the bulb all together if possible. even just moving the black rubber thingy i could hear it make strange noises. another forum suggested i cut the two ends of the fuse then slide it out from under the bulb but i need more info.

Strange noises? Maybe it's physicaly broken.

jetblue

nah its just wire creaking and im paranoid with it  :D

jetblue

#5
another techy at neo geo forums convinced me to bridge it:



it worked and i had backlite restored but after a few minutes of gameplay my right hand started to get warm. Turned it off immediately and opened it up,the area of the bridge was very hot and so was the tiny transformer near it. the other side of the bulb was cool. Im sure it would of heated up to point of fire. the bridge was a failure.

So i took this opportunity to de-solder the resistor/fuse:

came out successful without damage to the rest of the unit.
has the words written around it:

SEFUSE
SM095B0
(upside down triangle symbol)321
100 °C
1A 250v~

none of my junk boards have one. can anyone point me in the right direction where to get one? or a suitable alternative replacement? and cheap too,dont want to fork over $10 for 20 fuses  ;D


update:
after some research on the web found out is not a reistor/ fuse just a thermal fuse. so my problem has to be something else. i think it has to do with the power board of the game gear. a cap on it must of blown or something so il begin to change all the caps on it. any thoughts?

brettlee

This sounds very similar to the problem I'm currently facing with my GG! Except that mine's heating excessively on the left leg. Looks like yours heated up till the fuse gave up and forces it to disconnect the Flouro circuit.. Have you been able to fix this yet?

jetblue

hey brettlee,im kinda stalled at the moment trying to get a replacememnt GG to do some part swaps to narrow down the problem. Also im trying to get a better multimeter and some other stuff before i continue. if it takes me a month or a year i will have it fixed! or found out why it died.

brettlee

It probly is a dying tube. Just replace it and everything works back in order.. :) Please report your progress here as I'm interested in anything Game Gear related.. ;)

jetblue

#9
here is the tube,came off very easy and clean:




as you can see the end that blew the fuse is darker than the other and has melted remains of the rubber housing,more melted rubber on the other side.
Proof positive of a bad bulb. Sadly no makers mark or product number so finding a replacement will be almost impossible but i will try  ;D



and no thats not a meth pipe!  ;)

viletim

Part number BF8109-TA-1P4 from JKL Lamps (USA) looks like a close fit.

brettlee

Gosh.. that tube looks real nasty! Viletim found a possible replacement so you might wanna give that a try. Pls Let us know if it does work.. :D

jetblue

thanks,but the specs sheet on that model says its a bit too big. the game gear tube measures 97 mm by 7.5 mm.

jetblue

been doing some searching. very difficult to find a tube close to the GG size and look. The one you posted about brettlee seems the closest but something i noticed on the specs.

bf8109-ta
109mm by 8.2mm
Its a hot cathode fluorescent lamp or HCFL with specs of lamp current(mArms) IL 33,lamp volatge (vrms)50,watts 1.66,filament current IF (mArms) 250,brightness 18000 (cd/m2)

everywhere i looked for backlite for lcd's say to use cold cathode fluorescent lamps or CCFL. Can i use a HCFL in the GG?

Or should i look for one smaller like this one:

BF2698-20b
98mm by 2mm
Cold cathode CCFL,operating lamp current marms 5 some plus looking symbol and a 1,starting circuit volatge vrms 690,operating lamp volatge vrms 275,brightness 30,000 typ

Theres also this one on ebay used for cars:
http://cgi.ebay.com/Vastech-Dual-White-4-Cold-Cathode-CCFL-Light-Kit-US_W0QQitemZ330323136645QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item330323136645&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A15|39%3A1|240%3A1318|301%3A0|293%3A1|294%3A50#ebayphotohosting

CCFL 4 inches and smaller in diameter,says 2 in one. i figure i can remove them from it and splice them into my game gear.

what do you guys suggest?

jetblue

have abandoned my bulb search for this white led replacement:



http://pipe-organ-wolf.livejournal.com/5865.html


*throws all tube research in the trash*  ;D
will preform this mod soon.

djlooka

Hi, I've successfully performed the mod you quoted (the one by Tibia).
I've also slightly upgraded it, to increase the backlight uniformity.
If you can wait, I'm going to post it to my blog next week.
Cheers,
Luca

djlooka

http://desperatenerd.wordpress.com/gamegear-led-mod-photogallery/

Sorry, no time for the howto.
Have a look at the gallery, it covers the whole process, might be enough self-explanatory...

bigsanta

Excellent,though i would have used a few butt splices for picture 41.