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NEC TG-16/TE/TurboDuo => TG/PCE Repair/Mod Discussion => Topic started by: dougal on June 25, 2013, 04:24:09 AM

Title: White PC Engine sound problem
Post by: dougal on June 25, 2013, 04:24:09 AM

The sound from my white PC Engine is only working on the RIGHT channel. From the left it is very very low and with a light hiss.

I've tried it using the "french" RGB box from ebay and also with a home made composite av cable which attaches to the expansion port.

So seeing as I used 2 different options it is established that the problem is with the console itself. I've tried 3 different TV's too.

When I got the console about 3 weeks ago the sound was fine from both left and right.

Is it possible that I damaged something while attaching the home made cable ? Maybe a short or something ? The pins look fine.

Is it also possible that a capacitor for that audio channel blew ?

Please help me as although it is not a huge issue it is really frustrating me. Thanks  8)

Title: Re: White PC Engine sound problem
Post by: Fidde_se on June 28, 2013, 06:28:57 AM

You could easily have shorted the output, if you'r lucky you haven't burned a chip but just some OP amp.

usually when in mono only left channel is used, so I guess thats whats used for the RF but cant say for certain.

get any audio when used in RF?

Title: Re: White PC Engine sound problem
Post by: dougal on June 28, 2013, 06:57:50 AM

I cannot get audio in RF because my TV does not support the Japanese NTSC system.

Title: Re: White PC Engine sound problem
Post by: Keith Courage on June 29, 2013, 08:47:30 AM

You can check if there is any audio by tapping the sound directly on the Hu6280 chip inside the system. Pin 17 and 18 are the two audio channels. Best way to do this is get an old crappy RCA cable. Cut one end off. Touch the ground to any grounding point on the system and then try touching the positive center end to either audio pin 17 or 18. This will tell you if the main chip is still supplying audio or not.

http://www.gamesx.com/wiki/doku.php?id=hu6280_netlist

Title: Re: White PC Engine sound problem
Post by: ApolloBoy on June 29, 2013, 11:22:25 AM

Quote from: Keith Courage on June 29, 2013, 08:47:30 AM

You can check if there is any audio by tapping the sound directly on the Hu6280 chip inside the system. Pin 17 and 18 are the two audio channels. Best way to do this is get an old crappy RCA cable. Cut one end off. Touch the ground to any grounding point on the system and then try touching the positive center end to either audio pin 17 or 18. This will tell you if the main chip is still supplying audio or not.

http://www.gamesx.com/wiki/doku.php?id=hu6280_netlist

I think there's resistors that are connected to those two pins, tapping from those would be a lot safer than the small pins of the HuC6280.