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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: xinsizionx on February 14, 2015, 12:53:10 PM

Title: Pc engine white, No Video.
Post by: xinsizionx on February 14, 2015, 12:53:10 PM

hello, i just picked up a white pc engine rf with no video. the unit gets power and the fuse checks out fine. when hooked up with rf, i just get a flicker on the static screen. i ran a fast video and ground from the composite out on the back, the unit gets a black screen and if you mess with the jack the screen will flicker. any ideas? thanks

Title: Re: Pc engine white, No Video.
Post by: Keith Courage on February 14, 2015, 04:07:08 PM

to use a PC Engine on a US television via the RF Jack you have to set your television to channel number 96.

give that a try.

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 14, 2015, 04:49:00 PM

i can't even get composite video. i get a blank screen.

Title: Re: Pc engine white, No Video.
Post by: Keith Courage on February 14, 2015, 07:01:22 PM

hmmm, maybe the internal fuse is blown?

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 15, 2015, 12:04:07 AM

do you mean the 1 amp fuse by the 7805? i get continuity off of it.

Title: Re: Pc engine white, No Video.
Post by: SignOfZeta on February 15, 2015, 08:55:12 AM

Does it make sound? I ask because so far we don't know for sure that the cart is connecting well.

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 15, 2015, 10:17:29 AM

Thanks for the reply, but no sound either.

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 16, 2015, 07:06:32 AM

so i checked all the caps and they seem fine, i check the 7805 and thats working, the fuse is fine, i cleaned and reflowed chips. no matter what i just get a black screen. with or without a hucard. i cleaned the pins too. i looked for bad traces and the board seems to be in good shape.

Title: Re: Pc engine white, No Video.
Post by: SignOfZeta on February 16, 2015, 07:47:14 AM

Is the screen ever any color other than black? Like, is it sometimes either green or white?

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 16, 2015, 08:00:47 AM

no, solid black all the time. can it be the video chip?

Title: Re: Pc engine white, No Video.
Post by: pnauts on February 16, 2015, 09:30:46 AM

If possible check the Hucard slot if there is no misalignement or damaged pins.
Did you test with a verified Hucard ?

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 16, 2015, 10:56:38 AM

I check and cleaned every pin and I used 2 working hucards that work on my duo.

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 16, 2015, 11:03:23 AM

Do you know where I can find a replacement huc6260?

Title: Re: Pc engine white, No Video.
Post by: thesteve on February 16, 2015, 02:01:47 PM

from another machine only
wouldnt go there yet
any sync (does the TV recognize that its connected)

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 16, 2015, 07:21:01 PM

Not even a flicker when I hit the power.

Title: Re: Pc engine white, No Video.
Post by: thesteve on February 16, 2015, 07:34:29 PM

that doesnt sound like a chip failure
sounds more like something isnt connected
try to get video from pin40 HUC6260
if not even a flicker you not getting power/ground

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 17, 2015, 12:35:03 AM

its a pretty rough setup, but i have a wire to ground on the ext port and a wire to pin 40 on the c6270 hooked up to a rca jack. most of the time i can get a flicker, but sometime i still get a solid black screen.

Title: Re: Pc engine white, No Video.
Post by: thesteve on February 17, 2015, 06:07:40 AM

try a meter on pin40

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 17, 2015, 08:04:36 AM

It reads 4.3v

Title: Re: Pc engine white, No Video.
Post by: thesteve on February 17, 2015, 08:24:46 AM

that sounds like a white screen
got a different TV to try?

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 17, 2015, 08:45:21 AM

i tried another tv, one that will not allow you to change input unless it detects a source. it allowed me to change and then displayed no signal.

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 17, 2015, 10:46:17 AM

while checking the soldering for pin 40, i lifted the leg and the pad. i ran a jumper wire from the leg to the via and I'm getting 2.083v now. i know i probably killed this. i couldn't be more upset at myself.

Title: Re: Pc engine white, No Video.
Post by: thesteve on February 17, 2015, 11:51:15 AM

2.083V is a good voltage at pin40 with it running correctly
sounds like you may just have a TV compatibility issue
whats your TV?

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 17, 2015, 12:08:51 PM

so before i had 4.3v, now i messed up the leg and in getting the right voltage? lol ill try this again. the tv i first used is the one i have numerous retro console on, plus the pc engine duo you helped me fix.

Title: Re: Pc engine white, No Video.
Post by: thesteve on February 17, 2015, 12:16:16 PM

ok if the duyo works, the tv should be fine
the 4.3 was a no boot (possible dirty hu slot)

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 17, 2015, 12:25:00 PM

the 4.3v was with no card, just checking with a multimeter. the 2.083v was with no card as well, but after i lifted the pad and ran a jumper. i tried 3 tv's and all the same thing.

Title: Re: Pc engine white, No Video.
Post by: xinsizionx on February 17, 2015, 12:31:31 PM

i tried it on a sony trinitron tube tv(my retro setup), an LG lcd, and an insignia lcd.