PC Engine GT/Turbografx video troubleshooting help

[Skykid]

I've been searching google for some info on this and found some information regarding the video capacitor causing issues with the LCD display over time. However, as I've just got this, I wanted to run the symptoms by you guys to find out whether or not the activity is normal, or if the capacitor is dying:


- I played the GT consistently and fine for around 30 minutes and suddenly the image flickered off and back on again. It did this a couple of times and then went off completely. The backlight was still on and the game was still running fine (I was still able to hear myself playing it.)
I just wanted to know, what usually happens when the batteries die on your GT - do you lose the entire thing, or just the image? When I put in a fresh set of batteries, it seems ok again, but swapping between the sets (one used, one new) the used set of batteries might give me a picture for around ten seconds before the image goes progressively dark and then disappears. But the batteries are still powering the machine, since it's still running just with no picture. -

Hazarding a guess, I thought that the video cap is on its way out, and the fresh batteries are just boosting it for a short while. If anyone can elaborate on this or point me in the right direction by letting me know what usually happens when the batteries die, that would be great.

Also, which AC adaptor can I use with the GT for soak testing? Will my normal PCE briefcase one work?

Thanks all

[ApolloBoy]

If your PCE GT hasn't the caps replaced it needs to have them replaced now. All of the caps in the TE/PCE GT go bad and they could potentially cause the problems you're having. When your batteries die, the screen contrast goes up before it dies completely.

As for the AC adapter, the one from the CD-ROM2 setup won't work as the tip is too large and doesn't supply the correct voltage.

[Skykid]

If your PCE GT hasn't the caps replaced it needs to have them replaced now. All of the caps in the TE/PCE GT go bad and they could potentially cause the problems you're having. When your batteries die, the screen contrast goes up before it dies completely.

As for the AC adapter, the one from the CD-ROM2 setup won't work as the tip is too large and doesn't supply the correct voltage.

I have plenty of retro consoles about, do you know any with AC adaptors that might be compatible?

Regarding battery failure, does the entire system cut off when the batteries die (after the screen brightness) as in, sound, game and picture all at once?

I tested with those new batteries and got to stage 5 of Tiger Heli unhindered, and then the screen went out again.

[PC Engine Fan X!]

It's generally recommended to get/peruse the official NEC Turbo Express A/C adapter or NEC GT A/C adapter for testing purposes. The USA region TE A/C adapter has these specs listed on the sticker label:

----------------------------
Product Code: HES-ACA-04
Input: AC120V 60Hz 13W
Output: DC7V 700mA

For Use with Video Game Machine Class 2

KR NEC Technologies, Inc. Made In Taiwan
---------------------------

Both the NEC TE / NEC GT and both variants of the Atari Lynx I & II are known to be notorius battery guzzlers/hogs. They seldomly last around three to four hours tops -- this is using alkaline batteries, of course. Considering that both the GT & TE use an Epson produced TFT active matrix LCD screen, it likes to suck up as much power/juice possible with them alkaline batteries.

Now if you use the better rechargeable batteries say like the Sanyo Eneloop (or the Duracell rechargable double "AA" ones -- they're Eneloop batteries but with the Duracell brand slapped on), your duration/playing time will be increased a bit longer, especially if you use the higher rated (2000 mAH and up) capacity rechargeable AA batteries. Any fine hobby shop will carry/sell the higher rated hobby grade rechargeable AA batteries for your gaming needs. Might as well pick up a good battery charger when buying them AA batteries.

There was a time when NEC did sell an official TE rechargeable battery pack that was sold Stateside during the early 1990s but I never picked one up when TTI was "going under the bridge" in late 1994-early 1995.

PC Engine Fan X! ^_~

[Ed Oscuro]

My own GT (which I'm certain needs a cap replacement) had the video progressively dimming, until it appeared unusable. It wasn't flickering, but just a constant dimming. This was without a battery pack; instead I had a wall wart supplying DC to a car power adaptor (hey, it works).

[Skykid]

Yep, basically that capacitor isn't pulling its weight anymore. It comes to life if you leave it for an extended period or feed it siz fresh ones, but it eventually craps out after a short while of play, leaving the game running without an image.

I've returned it to the seller with a new capacitor and hopefully It'll come back a worker!

Thanks for the info, good to know it's just standard practice to replace caps on GT's.