Page 1 of 2
TT030 C302406-001 REV H
Posted: Sat Jul 21, 2018 5:15 am
by Steve
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
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.
Re: TT030 C302406-001 REV H
Posted: Wed Dec 04, 2019 2:54 am
by tjam
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.
Re: TT030 C302406-001 REV H
Posted: Wed Dec 04, 2019 4:20 pm
by Atarian Computing
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.
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...
Re: TT030 C302406-001 REV H
Posted: Wed Dec 04, 2019 6:37 pm
by ari.tao
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.
On my TT Rev.H it seems to be brown-black-black-gold.
But I can´t read what is written underneath.
Re: TT030 C302406-001 REV H
Posted: Wed Dec 04, 2019 6:55 pm
by Atarian Computing
Mine (REV.C - PGA model, C301763-001 REV A):
- LD01.png (671.48 KiB) Viewed 6361 times
Re: TT030 C302406-001 REV H
Posted: Wed Dec 04, 2019 7:08 pm
by tjam
Atarian 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...
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 inductor