Help repairing a dead TG-16

[jelloslug]

I have recently acquired a dead TG-16.  It will power on but only display a colored screen.  The previous owner made several attempts to repair including re-capping the system and reflowing the card slot.  I completely unsoldered the slot and re-solder it and cleaned the slot thoroughly.  I have also check all the connections from the card slot to the 6280 chip.  Any thoughts?

[crans]

Check every via and trace around the compositor for continuity I have repaired many mucked up diy cap jobs.   Look ar all component for solder splash.

[jelloslug]

From what I understand it was dead before the cap job.  I looked over the cap replacement, touched up a few things with no results...

[bust3dstr8]

Seems like the 6280 isn't booting. I would check the reset circuit (D101, R101, C101) and the clock circuit (R104, R107, C103 and OSC101) If you have a logic probe you can check the circuits directly on the 6280 inputs.

[jelloslug]

Seems like the 6280 isn't booting. I would check the reset circuit (D101, R101, C101) and the clock circuit (R104, R107, C103 and OSC101) If you have a logic probe you can check the circuits directly on the 6280 inputs.

I don't have a logic probe right now but I checked all the circuits and components that you listed and they are good.

[bust3dstr8]

I would invest in a logic probe...without it your just taking random stabs in the dark.

[thesteve]

also some games get sound if the 6280 boots
the 6260 and 6270 do connect to the data bus and i have seen some 6270 chips with shorted data pins prevent boot
for a tg16 taking it to the hoop should have sound without 60 or 70 chip running
if the screen color changes sometimes the 60 is likely working correctly
note a black screen is typical for 60 and 80 running code 70 dead so no boot is most likely

[jelloslug]

also some games get sound if the 6280 boots
the 6260 and 6270 do connect to the data bus and i have seen some 6270 chips with shorted data pins prevent boot
for a tg16 taking it to the hoop should have sound without 60 or 70 chip running
if the screen color changes sometimes the 60 is likely working correctly
note a black screen is typical for 60 and 80 running code 70 dead so no boot is most likely

Thanks, I'll give that game a shot and report back.  When I power it up I get a yellow-orange screen most of the time and occasion white or some other light color.

[thesteve]

Yes dishwasher,  no anonymous prayer

[jelloslug]

I check the oscillator on a scope and it's working perfectly.  I also check for sound with Takin' it to the Hoop and there was no sound at all.

[thesteve]

then id look for a problem on the data bus