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.
^ 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.
TT030 C302406-001 REV H
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Re: TT030 C302406-001 REV A
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
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 ?
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
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- Joined: Tue Aug 22, 2017 4:27 am
Re: TT030 C302406-001 REV H
I'm certain that there are two revisions of REV.H. Let me show ya:
Here is the earlier revision from this forum:
And another early H.
Here is proof that C302406-001 REV A boards can be REV.H Notice how the bottom left corner is green instead of metallic?
Let's look at another newer REV.H: 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.
Here is the earlier revision from this forum:
And another early H.
Here is proof that C302406-001 REV A boards can be REV.H Notice how the bottom left corner is green instead of metallic?
Let's look at another newer REV.H: 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
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.
Re: TT030 C302406-001 REV H
My eyes are pretty tired after I tried to figure out what is that quite big light green resistor located at near PSU connector and c120 capacitator Is that 10ohm resistor? I'll soon try to bring life to TT that has some components missing and that resistor is one of them.
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Re: TT030 C302406-001 REV H
Yeah, you happened to run into one of the mysteries. It's marked as LD01 on the silkscreen. However, it does not appear in the schematic. I should know as I've painstakingly re-created it in KiCad.tjam wrote: ↑Wed Dec 04, 2019 2:54 am My eyes are pretty tired after I tried to figure out what is that quite big light green resistor located at near PSU connector and c120 capacitator Is that 10ohm resistor? I'll soon try to bring life to TT that has some components missing and that resistor is one of them.
It appears to be part of the TT ECL Video Subsystem. Components here get a letter "D" added after the regular designator. C becomes CD, R becomes RD, U becomes UD, etc. By that convention, LD01 would be L, which typically is a designator for a coil, inductor, bead, ferrite bead. It sure doesn't look like one. Also, there are no other "L" components on the whole board.
Based solely on looks, it could be a resistor or a capacitor. There are several smaller green resistor-looking caps on the board.
So, TL;DR is, no clue...
Re: TT030 C302406-001 REV H
On my TT Rev.H it seems to be brown-black-black-gold.tjam wrote: ↑Wed Dec 04, 2019 2:54 am My eyes are pretty tired after I tried to figure out what is that quite big light green resistor located at near PSU connector and c120 capacitator Is that 10ohm resistor? I'll soon try to bring life to TT that has some components missing and that resistor is one of them.
But I can´t read what is written underneath.
Falcon, TT & some more
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Re: TT030 C302406-001 REV H
Mine (REV.C - PGA model, C301763-001 REV A):
Re: TT030 C302406-001 REV H
Ah I see.. It surely looks odd, because it's quite big to be 10ohm resistor, but because of color coding I assumed it has to be resistor. I just figured out that axial caps and inductors also has color coding As far I can tell from pictures (I'm really not sure) it looks to have brown, black and black bands and 10% tolerance Probably it's not resistor because it's marked to be "L" component, but axial inductorAtarian Computing wrote: ↑Wed Dec 04, 2019 4:20 pm Yeah, you happened to run into one of the mysteries. It's marked as LD01 on the silkscreen. However, it does not appear in the schematic. I should know as I've painstakingly re-created it in KiCad.
It appears to be part of the TT ECL Video Subsystem. Components here get a letter "D" added after the regular designator. C becomes CD, R becomes RD, U becomes UD, etc. By that convention, LD01 would be L, which typically is a designator for a coil, inductor, bead, ferrite bead. It sure doesn't look like one. Also, there are no other "L" components on the whole board.
Based solely on looks, it could be a resistor or a capacitor. There are several smaller green resistor-looking caps on the board.
So, TL;DR is, no clue...