Turbo Express

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Chip Info


Bad Capacitors

Turbo Express / PC-Engine GT handhelds have exceptionally bad problems with surface-mount capacitors. All TE units should have their capacitors replaced as soon as possible. Without total capacitor replacement, a Turbo Express unit is guaranteed to fail.

In the past it was common to only replace the caps related to audio or to the display. Really all of the caps will be bad, so it is in your best interests to replace them all.

One more time: Do not replace only audio or display caps! Change them all!!


Common Problems

Everything listed here is contingent on 100% capacitor replacement. If you're repairing a Turbo Express with original caps, you need to change them before doing anything else. They cause a litany of unsolvable problems.

Using batteries, image is bright or brightness changes in time with sound 
Replace batteries or test with A/C adapter.
Display backlight does not turn on, fuse may or may not also blow 
Check for shorted transistor Q900 / Q901
Turn on/off randomly when using wall plug 
Damaged DC jack or DC plug - see the #A/C Adapter Connection note below


Capacitor List

Purchase these parts as a kit

When installing one of our leaded kits, with the exception of the 100uf 16v replacements, most caps should be installed laying flat.

Turbo-Express-Cap-Map.png
CC100	100uF	16v
CC101	33uF	6v
CC102	33uF	6v
CC103	100uF	6v
CC104	100uF	6v
CC500	100uF	16v
CC501	4.7uF	35v
CC502	4.7uF	50v
CC503	22uF	35v
CC504	100uF	6v
CC505	100uF	6v
CC700	100uF	6v
CC702	470uF	6.3v
CC703	100uF	6v
CC704	10uF	16v
CC900	100uF	16v
CC901	22uF	6v

Controller PCB Cap:
CC800	47uF	6.3v


Adjustments

  • VR500: Horizontal Sync / Horizontal Centering
    • This adjustment moves the screen image left & right. Adjusting too far will destabilize the picture.


  • VR501: Vcc adjust
    • TE units are not restricted to TTL voltages. The factory setting seems to be around 4.5V.


A/C Adapter Connection

Soldered center pin
Both the A/C Adapter jacks, and the A/C adapter connectors seem to flake out and become unreliable.

To help the power jack, I like to solder the center conductor pin. Its rivet-like connection seems to loosen up over time. New DC jacks and New DC plugs are also available.