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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: ApolloBoy on February 21, 2013, 05:55:26 AM

Title: Trying to locate short on TG-16 board
Post by: ApolloBoy on February 21, 2013, 05:55:26 AM
So I got a region modded TG-16 recently and I decided to remove the RF modulator in favor of a mini-DIN jack so I could mod it for RGB and composite. When I first tested it, it worked fine but it turned out I had the video and audio mixed up so it didn't work first try. So then I wired it up correctly and now for whatever reason the 5V and ground are shorted. I've looked at the region switch, caps, voltage regulator and everything else I can think of, and everything looks fine. I can't for the life of me figure out where the hell it's shorted, anyone have any ideas?
Title: Re: Trying to locate short on TG-16 board
Post by: Keith Courage on February 23, 2013, 04:06:48 PM
You are not the only person to have had this happen to them. Around 3 years ago I took an RF jack out of a TG16 and it killed it. Meaning the system would no longer turn on and probably had the same short you mentioned. Fuse was still good but no picture or audio. I checked all over where the RF used to be but could not find any problem areas. Luckily the system was just a spare of mine so I gave up and used it for parts. Still a bummer nevertheless. I hope you get it figured out.
Title: Re: Trying to locate short on TG-16 board
Post by: ApolloBoy on February 24, 2013, 11:42:38 AM
You are not the only person to have had this happen to them. Around 3 years ago I took an RF jack out of a TG16 and it killed it. Meaning the system would no longer turn on and probably had the same short you mentioned. Fuse was still good but no picture or audio. I checked all over where the RF used to be but could not find any problem areas. Luckily the system was just a spare of mine so I gave up and used it for parts. Still a bummer nevertheless. I hope you get it figured out.
I don't think removing the RF did it as it actually turned on the first try. On that first try I had the video and audio accidentally swapped on the mini-DIN connector I was using so I'm thinking that must've shorted a cap or resistor somewhere down the line. I'm really hoping it's not one of the major chips as that would be a royal PITA to replace.
Title: Re: Trying to locate short on TG-16 board
Post by: Keith Courage on February 24, 2013, 01:28:10 PM
Did you already check for video or audio at the HU6260 chip itself?
Title: Re: Trying to locate short on TG-16 board
Post by: ApolloBoy on February 24, 2013, 02:14:44 PM
Did you already check for video or audio at the HU6260 chip itself?
It worked through RF before, plus I can't check now since 5V and ground are shorted.
Title: Re: Trying to locate short on TG-16 board
Post by: ProfessorProfessorson on February 24, 2013, 02:36:00 PM
If all you did was accidentally swap audio and video wires with each other, that is being outputted to the tv, so I don't see that as shorting anything to the point of causing real damage or anything. If you have a bright LED flashlight or something I would check over the thing thoroughly, both the top and bottom of the pcb, and see if maybe a stray solder spec or something has managed to cause your short. If you cant spot anything right away, and I know this will come off as kind of stupid, but try washing the pcb off in your dishwasher or spray nozzle at your kitchen sink or do a heavy alcohol scrub with a toothbrush. If its a stray solder blob you cant seem to spot, maybe the force of the water or whatever can knock it loose.
Title: Re: Trying to locate short on TG-16 board
Post by: ApolloBoy on March 01, 2013, 10:38:14 AM
Gave the whole board a nice scrub with some rubbing alcohol and still nothing.

EDIT: Replaced a few caps and all seems to be well now!