Page 1 of 1

TT030 C302406-001 REV H

Posted: Sat Jul 21, 2018 5:15 am
by Steve
It has a very strange multi-layered modification on the sound chip people haven't seen before. Does anyone know what that was for? Thx.

edit: updated the title to rev H as suggested by Atarian Computing.
20170304_112017.jpg (6.08 MiB) Viewed 1414 times
20170304_112025.jpg (6.04 MiB) Viewed 1414 times
20170304_112030.jpg (5.83 MiB) Viewed 1414 times
20170304_112044.jpg (4.48 MiB) Viewed 1414 times
20170304_112053.jpg (5.63 MiB) Viewed 1414 times
20170304_112904.jpg (4.78 MiB) Viewed 1414 times
IMG_20180718_212130.jpg (1.39 MiB) Viewed 1414 times
^ Oddly on the top of the motherboard in the bottom right hand corner where it says REV_____ it has a very faint hand stamped 'B'. I don't know why that doesn't correspond with the PCB revision on the underside pictured above.

Re: TT030 C302406-001 REV A

Posted: Sat Jul 21, 2018 5:56 am
by Atarian Computing
Nice pictures! TT revisions are a mess. Your's probably is a REV.H. I've seen many C302406-001 REV A boards with REV.H topside.

Re: TT030 C302406-001 REV H

Posted: Sat Jul 21, 2018 9:03 am
by exxos
Interesting.. Pins all bent on the IO ports on the YM chip.. Wire goes to "DD enable" to the 1772 by the looks of it. I will take a guess its a factory fix ? Maybe you could take out the YM chip and see if there is any tracks visible ?

Re: TT030 C302406-001 REV H

Posted: Sat Jul 21, 2018 10:35 am
by Atarian Computing
I'm certain that there are two revisions of REV.H. Let me show ya:

Here is the earlier revision from this forum:
20180121_104548.jpg (3.24 MiB) Viewed 1385 times
InkedTTha_LI.jpg (726.05 KiB) Viewed 1385 times
InkedTThb_LI.jpg (860.32 KiB) Viewed 1385 times
InkedTThc_LI.jpg (1 MiB) Viewed 1385 times

And another early H.
IMG_0030.JPG (231.8 KiB) Viewed 1385 times

Here is proof that C302406-001 REV A boards can be REV.H
Atari_TT_Rev____unten_rechts.jpg (47.11 KiB) Viewed 1385 times
Atari_TT_Rev_H_R├╝ckseite_oben_rechts.jpg (22.59 KiB) Viewed 1385 times
Atari_TT_Rev_H_unten_links.jpg (43.35 KiB) Viewed 1385 times
Notice how the bottom left corner is green instead of metallic?

Let's look at another newer REV.H:
DSCF1294_s.jpg (360.62 KiB) Viewed 1385 times
InkedTThf_LI.jpg (823.73 KiB) Viewed 1385 times
InkedTThe_LI.jpg (822.99 KiB) Viewed 1385 times
InkedTThd_LI.jpg (834.79 KiB) Viewed 1385 times
Now compare these pictures to yours.

So my conclusion so far is that if you were to turn the earlier REV.H around it would probably read C301763-001 REV D. I've never even seen a picture of a TT board with REV.D on the topside.

Re: TT030 C302406-001 REV H

Posted: Sat Jul 21, 2018 11:35 am
by Steve
Very interesting. And yet none of them have that Yamaha chip mod. I would take it apart but it's kind of complicated, as it has got a PCB layer underneath it with an IC or two underneath.