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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: bdoi on March 22, 2021, 02:03:45 AM

Title: LT not working
Post by: bdoi on March 22, 2021, 02:03:45 AM: Hi
I have a LT that do nothing when power on.
I mean really nothing, not even the green led.
I opened it and checked the fuse, but it was ok. The power switch seems to be good too.
I know that I have to change the capacitors but even with bad caps the green led should switch on, right?
Any advice of what to check before a whole changing caps ?
Title: Re: LT not working
Post by: MasterofBiscuits on March 22, 2021, 01:25:41 PM: Have you measured voltage anywhere on the board? A good start would be to trace the power from source through the board.

Honestly though, I would do a full recap and clean before anything else, otherwise you could just be wasting your time. With fresh caps you have a solid baseline to work from. I have not worked on an LT but on other systems bad caps can cause the machine to appear dead.
Title: Re: LT not working
Post by: bdoi on March 22, 2021, 05:24:14 PM: After another check, the component t500 (coil?) Is broken.
Is anyone knows a replacement part number please??
Title: Re: LT not working
Post by: Keith Courage on March 22, 2021, 10:35:42 PM: There still a chance of no power with bad caps. Especially if one is shorting out somewhere on the board.

Also, you might want to check with both power inputs. The left side input is for when it is in use by itself. Right side input is for when the system is docked for CD drive use.
Title: Re: LT not working
Post by: bdoi on March 23, 2021, 02:55:37 AM: any one knows reference or name of this broked part (T500)? ??
(https://i.postimg.cc/JGLtgwLq/20210323-071908.jpg) (https://postimg.cc/JGLtgwLq)

(https://i.postimg.cc/QHJVZ6Nr/20210323-073418.jpg) (https://postimg.cc/QHJVZ6Nr)
Title: Re: LT not working
Post by: xelement5x on May 28, 2021, 06:23:17 PM: I think on PCBs T normally denotes a Transformer IC, given it's next to the power jack it could be step down transformer or something?
Title: Re: LT not working
Post by: tam23 on February 11, 2022, 02:35:04 PM: Hi
i am new to the forum but not the pc engine.
i too have a faulty T500 transformer on my LT
This was discovered when it was recapped.
now the monitor does not work.
everything else does.
i have looked everywhere for a replacement T500 transformer but just hit dead ends.
was hoping the members on here could steer me in the right direction.
Any information would be gratefully received.
Title: Re: LT not working
Post by: TheShadowRunner on February 13, 2022, 06:23:28 AM: Quote from: tam23 on February 11, 2022, 02:35:04 PM
i have looked everywhere for a replacement T500 transformer but just hit dead ends.
was hoping the members on here could steer me in the right direction.
Any information would be gratefully received.
Hmm you can try to contact Console5 for availability, they sell such parts (https://console5.com/store/turbo-express-pc-engine-gt-backlight-transistors-q900-q901-turboexpress.html). Or another member here might know.
Title: Re: LT not working
Post by: tam23 on February 14, 2022, 02:34:40 AM: Tried console5,they suggested butchering a gt to get the part.
dont know if i am being naïve here but thought as its not working 100% would an lcd upgrade even be an option?
Title: Re: LT not working
Post by: Keith Courage on February 15, 2022, 08:27:06 PM: Does the LT play audio for any game in its current condition? Then yes, you could do a composite screen install for it. The screen to buy would be a 5" widescreen composite screen. They have the option to set 4:3 for the aspect ratio which ends up being the correct size for the LT screen opening.
Title: Re: LT not working
Post by: tam23 on February 17, 2022, 11:40:42 AM: Hi,yes audio is perfect on the unit coming out the internal speaker.
I am happy to post to you and pay what’s necessary to get this mod done.
dont want to scrap it.
it works fine on av out aswell to an external screen.