Help my Famiclone "Subor D21" (AV fix & overclock)

[Kangsteri]

Sorry in advance. I'm kind of a newbie and amateur with these. I also speak English and electronic language quite poorly. But I just started to study the anatomy of my Famiclone (Subor D21). I know that these "NOAC:s" are usually very bad. But this one is nearly good cause it supports the Famicom features well. So i would like to try mod this anyway. I just have two problems:

- Proplem one is that this has the AV outputs, but with jailbars... I suspect its partly caused by cheap parts. So can i make or buy better composite amplifier? Seems like there is some different ways to do the mod version. And according to GameTechUS on Youtube, it counts if i use same quality components as the old NES. I could just buy the AV chip from him but he does not do clones... So does this have the pins for original signal?

- Proplem two is that it runs too slow. But seems like this uses external crystal oscillator. So can i "overclock" this to normal speed somehow? I know that the videopicture might go wrong and that it can cause other problems too. But i want to try anyway. According to some old forum post it might work.

Here is some pictures of the console =
Mainboard:
The missing pinmarks between P2D1 and GND are on other side of the wire that goes to controllers. From right to left =
- P2D0, P1D0 and Reset.
The upper wires that go to outputs are also marked on other side. From right to left =
- GND, VO / VCC (video out?), A (audio?), VI / VCC (video in?) and VIDEO
Seems like that KSY thing is crystal oscillator?

Under the mainboard (Those long wires with hot glue are the "oscillators" legs. It looks like it was made after the board. They have not even used all parts and jumpers that are marked on circuits):

And the output / powerboard:

[famifan]

V-IN comes from 7805 output (5V)
between V-in and VCC it has a power switch (of/on)
VCC is a power supply (+5V respestive to GND)

you definitely have pal system and it's known to be slow. So you can try to replace crystal for NTSC counterpart and set some jumpers for NTSC. Shit there are no silk screen marks about it

for the jailbars try to shield the NOAC glob-top chip with some piece of adhesive foil to ground

[famifan]

i have the similar board and it has jumper settings exposed to silk screen. Just wait for the pic a day or two

[Kangsteri]

Thank you very much Famifan! All help, critic and information with this project is appreciated. My main goal is to make it small as possible. So maybe i could fit it in NES cart. I will take away the circuit for controllers and connect them to mainboard. But i was thinking if i can take the outputboard away too? If i take the video and audio from the mainboard and make separated power transformer from the parts.
And yes, i forgot to mention that it is indeed PAL-B. But I'm from PAL region and used to slow. This just sounds extra slow. So what oscillator should i use? 3.579545Mhz? And can i just replace it with the current one, or make switch for it? I could test to overclock it too if i figure out what crystals to use. Is it 4.433619Mhz for overclock? And would tunable capacitor maybe help for that?
I didn't realise that i could make the ground foil for NOAC too Is it possible use like slice of aluminiumtape, or would it be better to use peace of real aluminium or copper and hotglue it on the chip?

And sorry 80sFREAK for the hi-res, i assume you mean the pictures. I'm not that used to post on forums. I got this rubbish cheap with some multicarts and NES-adapter... And cause Japan is almost other side of the world, i haven't even seen real Famicom with my own eyes. Or top loader. Of course i would use one if possible. But even this rubbish is currently asked about 150€ in here (boxed with zapper and some games), if i can see one on auction. I was really supriced how good it is for a clone, cause at least it has the AV and external crystal.

[famifan]

i was thinking about doing the same. I'm joining to the project 
Post Merge: April 06, 2013, 09:23:47 am

[Kangsteri]

I'm still not sure about anything what i do but I'm going to try something with this info:

Plan A:


- Overclock =
=============
Traces for crystal:
NOAC > Crystal > Thing 47/C2 (32,2k or 0,246M?!) > GND
NOAC > Crystal > Thing 22/C3 (38,7k or 0,323M?!) > GND

Maybe i could replace other "Thing" with 9-50pF Variable Capacitor for tuning?

I'm gonna use these crystals and maybe World championsip style switches for them + goldcart
- PAL Clock = 26.6017 MHz (original)
- NTSC Clock = 21.47727 MHz
- Optimal Clock = 28.3220 MHz

- Power transformer =
=====================
Will this work?

7805:
Thing 203 + 16V100uF, from +9v to GND = 43,2k or 0,276M?!
Thing 203 + 16V100uF, from +5v to GND = 5,9k or 0,005M?!
(I try to add led for power too. From +9v)

- Controllers =
===============
Controllers need to be all rewired with more and longer wires. I'm still not sure what connector to use.
I need at least 9 wires for P1, so Playstation style would be option. But DR15 15 Pin Female would fit to style. Also many old joysticks are used by DR15 15 Pin Male (same as famicom exp), so it would help with other controller mods.
2 Player switch can be used to pass the controller. But if you put both on, you can play Contra with two synchronised guys at same time

- AV Mod =
==========
80sFREAK style:
Video + GND > PNP Transistor > 100ohm Resistor
+5v > 150ohm Resistor
100ohm + 150ohm Resistors > 6.3v 33uF = Video out

NINTENDO style:

Video + GND > 2SA937 PNP Transistor
+5V > 300ohm or 330ohm Resistor
PNP Transistor + 300ohm or 330ohm Resistor > 6,3v 220uF or 10v 100uF Capacitor > "ferrite core" > 75ohm, 110ohm or 120ohm Resistor
GND > 560pF Capacitor + 75ohm, 110ohm or 120ohm Resistor = Video out

Both say they are the best way.. This one originally has only 16v 10uF and its too little.
Jailbars mostly seem to be cause of bad power, long leads, bad insulation and external distraction, like RF unit etc. I think I'm gonna do it the Nintendo way cause it has been used to remove the jailbars. Seems like many people also underrate the value of good insulation, ferrite core and ground foil.
I found some "MULTICOMP - MCAB 035090-33 - FERRITE CORE, CYLINDRICAL, 105ohm".
http://uk.farnell.com/jsp/displayProduct.jsp?sku=9265252&CMP=e-8976-00001011
Maybe i could use it in the end with 105ohm resistor? I'm gonna use external ferrite core too, it could reduse the jailbars also.
For audio i will use only mono output. And split the sound with cable.

Here is similar mod that someone else have made: http://www.overclock.net/t/323057/ign-nes-console-on-a-chip-mod-the-console-is-in-the-cartridge
(with jailbars ) This shows good idea. That extra controller ports are not really even needed if i just use the expansion port.
But i remember that i read some game supports even 5 players. So maybe the controller ports need to be there, just in case..

[famifan]

NOAC > Crystal > Thing 47/C2 (32,2k or 0,246M?!) > GND
NOAC > Crystal > Thing 22/C3 (38,7k or 0,323M?!) > GND
Thing 203 + 16V100uF, from +9v to GND = 43,2k or 0,276M?!
Thing 203 + 16V100uF, from +5v to GND = 5,9k or 0,005M?!

what do these bold texts mean?

[80sFREAK]

NOAC > Crystal > Thing 47/C2 (32,2k or 0,246M?!) > GND
NOAC > Crystal > Thing 22/C3 (38,7k or 0,323M?!) > GND
Thing 203 + 16V100uF, from +9v to GND = 43,2k or 0,276M?!
Thing 203 + 16V100uF, from +5v to GND = 5,9k or 0,005M?!

what do these bold texts mean?

Measuring resistance

C2, C3 and XTAL is common "externals" for build-in oscillators. One of them could be variable for fine adjusting frequency.

Whats gonna happend with syncro, when you will change XTAL 

[Kangsteri]

Yes, those texts are the components, connections and resistance measuring. For example "Thing 47" is  the component and the number that's on the side of it. And C2 is written under it, on the board. And 32,2k is the resistance.
I really don't know much about electronics. Or component names, functions, or how to draw them properly. But i understand some basics. Sorry. I'm just quessing and assuming most of this based on what other people have written and done. And using it with the little i know.
I'm not even expecting this to work. But i think its better to try than just let it be. And i posted this just to get more information and tips if someone knows better, or has been testing some of this. I don't think i will brake the consol with this. And even if i do it doesn't matter. Just like to experiment with these kind of things. Most worrying thing for me at the moment is the power transformer.
Whole overclock assumption is based on that someone was saying it might be possible if the crystal is external. And even he doubted it right immediately after that, in his next comment. Cause of the issue with cpu and ppu. But i would like to test this. Maybe there is some Subor magic that could make it work at least with NTSC crystal. The variable capacitor idea just came from some Sega NTSC mod.

[80sFREAK]

You can replace XTAL with ceramic variable capacitor, but it's the last thing on the "to do" list.
Measuring resistance will give you no useful information.
6561 chip might have switchable(by grounding some pins) prescaler for CPU/PPU and colour coder(PAL/NTSC), but that's all. Once frequency out of TV's tolerance, you will have no syncro and wrong pitch of sound.

If you want overclock, go for Famicom/NES. You still loose proper pitch except, probably, using extra CPU in test mode(only curtain revision support this, when registers accessible from outside), clocked with regular frequency.

[famifan]

what you called a "thing" is capacitor. No need to measure resistance on it unless you know how do it properly.

just use any equals ceramic caps laying around 12-22p for crystal's low/high pass filters

[Kangsteri]

Thanks! I was looking at the board with some more attention and realiced that all parts are marked clearly CN* = Connection, C* = Capacitor, R* = Resistor, J* = Jumper...
This obviously is originally designed to be one board. All missing parts in right top corner seem to be original video output. They go like this:
Video > 6.3v 22uF
GND > 12k Resistor + 6.3v 22uF > -6K8 Resistor + PNP 2SC945-B
GND > 150 Resistor > PNP 2SC945-E = video out
VCC > +6K8 Resistor
VCC > PNP 2SC945-C > 104 Capacitor > GND

Only thing that seems to be different than it supposed to, is the Capacitor 6 middle of the board. Its marked as 47uF but this is only 50v 1uF. It connects to GND and Reset.

[famifan]

Only thing that seems to be different than it supposed to, is the Capacitor 6 middle of the board. Its marked as 47uF but this is only 50v 1uF. It connects to GND and Reset.

it should be marked as 0.47uF (or 474). 1uF is okay. The bigger the capacitance the longer reset on power-up occures
Post Merge: April 09, 2013, 08:04:24 am
a doc about C2,C3 values > http://ecee.colorado.edu/~mcclurel/iap155.pdf

[Kangsteri]

Thanks for all the information. This really goes way over my league. I'm more trial and error kind of guy
I just assumed that the Subor was so cheap that they used same board and parts for PAL and NTSC. And it reads so on the board too..
For what i have seen, most PAL to NTSC mods recommend the variable capacitor. Seems like usually other PAL consoles are made by using other crystal and adding capacitor or jumper to some point.
So I originally had only two ways for trying NTSC:
1 - Put in the NTSC Clock and try to remove some capacitor or jumper.

2 - PAL NES runs a 26.601712MHz crystal using a 16x divider (1.66MHz CPU speed)
NTSC NES runs a 21.47727MHz crystal using a 12x divider (1.79MHz CPU speed)
Perhaps the 28.64 MHz crystal trick method would work for NTSC.

But i will order and try the 21.47727 MHz crystal. Witch will take some weeks.. And replace the 47p capacitor from C2 to same as C3 (22p).
If i understand Famifan right?
And yes,didn't see that there was hidden 0. before the 47uF. Sorry again  Its always good to ask stupid questions before making stupid actions...

[80sFREAK]

Perhaps the 28.64 MHz crystal trick method would work for NTSC.

for CPU, how about PPU?