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bytestorm

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No, they aren't needed because the pcb design is different (ceramic capacitors instead if electrolytic etc.)

For PCE console5 offers a suitable pcb: https://console5.com/store/assembled-ths7374-rgb-pcb-for-nec-turbo-grafx-turbo-duo-pc-engine.html
Yeah I see that the design is different, but the amp is the same. And there are no ceramic replacements on this board for 220uF electrolytic capacitors, they are just removed.
I was just curious to why and what reason there is to have them or not.

Thanks for the PCE site! Will check it out :)
 

SVM

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The big capacitors are not needed because of the 5.1MOhm pull-up resistors at the inputs (the voltage divider is 75/75 and the output signals are under 1V for black). ;)
 

ita123

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Originally the RGB PCB was the idea of member philenotfound of the German circuit-board.de forums but at the moment he is too busy to develop another revision of the PCB...

At the same time (the project was discussed in an open thread at circuit-board.de) I asked "RGB Bypass Master" borti4938 to help me out designing a PCB with proper impedance matching signals.

Meanwhile the PCB is ready and installed in my CMVS.

Neo Geo MVS RGB PCB.png



The picture looks awesome an I think no further revision is needed. :thumbup:

112339-Windjammers-png


If you want to try it out you can order the PCB from OSHPARK.com or AISLER.net. ;)

If you have some questions regarding the resistor values, capacitors etc. please ask borti4938. He is a real expert and I think his answers will be more specific than mine. ;)
Do u have this boards pre assembled, for sale?
 

bmp

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So glad to have found this thread! Just registered here to be able to reply.

Been searching here and there for months, for the ideal way to consolize my MVS board. Always find the same topics, many contradicting opinions, and the people who seem to know what they're talking about, well I usually don't understand most of what they're saying :)
I know how to solder though, so I'm really excited this to me unknown topic suddenly popped up in my monthly Google search.

At the same time (the project was discussed in an open thread at circuit-board.de) I asked "RGB Bypass Master" borti4938 to help me out designing a PCB with proper impedance matching signals.

Meanwhile the PCB is ready and installed in my CMVS.
Really interested to try this solution. Especially as it's made to do exactly what I need it for, instead of for example Tim Worthington's AV-Driver board, which seems more of an all round solution offering many options I don't need.

A few questions about your PCB:

* Can I just take R, G, B, and sync directly from the Jamma connector to the pcb, and the output straight to my SCART connector? Or do I still need to attenuate the signals in any way, use voltage dividers, before the signals go to the board?

* When using your PCB, does it result in correct brightness and color output, or do I still need to change any of that?

Thanks!
 

SVM

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Hi @bmp,

yes, you can take R, G, B, and sync directly from the JAMMA connector to the pcb, and the outputs straight to your SCART connector. There is no further attenuation etc. necessary.

Only the 5V line needs an additional 180 ohm resistor if you want to connect it to SCART pin 16.

To my opinion brightness and color output are correct and there is no need to change them (for reverence look at the photo of Windjammers - I think the color matching is fine there ^^ )
 

bmp

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@SVM

This is fantastic! Ordering the board and parts right away, very glad to have found this.
Will report back once I've tried it, could take a while though, too many projects going on. Some time 2019 :)

Thanks.
 
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Max_Power

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@SVM sorry for the noob question.

I got the board a few weeks ago from OSHPark but just got components yesterday. Built myself a board.

Does it matter the order the components are placed on the board ? as in Positive/Negative Ends. (Resisters and Capacitors) I know there is a marker for the THS7376 with PIN 1.

Also just to confirm,

the connections are: SYNC - R - G - B - GND - 5v
 

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SVM

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Hi @Max_Power :)
Does it matter the order the components are placed on the board ? as in Positive/Negative Ends. (Resisters and Capacitors)
No, the small resistors and capacitors have no polarity. Therefore you don't have to care about the mounting direction. Only the tantalum capacitor (the big one) has a polarity. Regarding to your photo it is mounted correctly.
the connections are: SYNC - R - G - B - GND - 5v
Yes, they are. :)
 

SVM

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Feel free to post some pictures and own impressions after you've installed your pcb. :)

THX in advance!
 

ita123

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I'm interesting in ordering the board from oshpark and solder the components myself.

I'm fairly ok in soldering , I managed to solder the 68k cpu socket on the neobios masta board, using a hotair station.

How hard is to solder the ths7374 in comparison to the 68k socket?

Can the board be used in a supergun build, using different jamma pcbs?

Thanks
 

SVM

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How hard is to solder the ths7374 in comparison to the 68k socket?
If you manged to solder the 68k socket than you won't have any problems regarding he THS7374. :)

Can the board be used in a supergun build, using different jamma pcbs?
I guess the pcb is not suitable to use in combination with superguns because they (mostly?) come with their own rgb(s) circuits.
 

ita123

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How hard is to solder the ths7374 in comparison to the 68k socket?
If you manged to solder the 68k socket than you won't have any problems regarding he THS7374. :)
Can the board be used in a supergun build, using different jamma pcbs?
I guess the pcb is not suitable to use in combination with superguns because they (mostly?) come with their own rgb(s) circuits.
I want to use it on diy supergun.
Thanks
 

Appley81

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I have made this pcb and used it on a mv 1c .. works fine but the brigthness level was much darker than other standard game consoles connected to my BVM. I presume the resistor vaslues are wrong
?
 

SVM

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Strange...

Other people responded to me that the picture looks fine on their CRTs or flat TVs...

Maybe a studio monitor handles the signals slightly different in comparison to consumer TVs?



Here are 2 photos of the pcb in combination with a PVM: https://www.instazu.com/media/2038492628158694641

I would say that the picture looks ok. On the 1st picture you can see that the brightness knob is centered...
 
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Appley81

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I think a version with adjustable RGB pots instead of the pull down resistors would be better. Catering to all the various mvs revisions and monitors
 
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