Super retro trio tear down - Taking apart the SR3.

[sean]

I got video on the nes side using the right side of the R90 connect to the left side or R83 but, sometimes on mario 3 the video glitches as in rolling over and the video is ultra crap on the snes and genesis when I connect .
Would, adding a 75 or 100 ohms resister fix that issue ?

[Ace]

A little research found me a post by Satoshi where he claims it is 750 on his console.

Sounds to me like someone at the Retro Trio factory made a typo when ordering parts -_-

750 is just the marking on the resistor, but as it's an SMD resistor, it's 75 + 0 zeroes, therefore the end result is 75 ohms. If it were a 750ohm resistor, the resistor's markings would read 751, 75 + 1 zero. To me, it seems he has his TV set too dark because, as I said, on all my TVs, the video looks perfectly fine with 75 ohms at R83.

[AlmostOriginal]

In the meantime here are some pics of my Ghetto Trio.

The wierd part about those "gray pass trough pcb cables" are that they creat wierd resistance over each other. Dont know why? :S But replace them with better/thicker cable or sheilded if you can find that.

[MaxWar]

750 is just the marking on the resistor, but as it's an SMD resistor, it's 75 + 0 zeroes, therefore the end result is 75 ohms. If it were a 750ohm resistor, the resistor's markings would read 751, 75 + 1 zero. To me, it seems he has his TV set too dark because, as I said, on all my TVs, the video looks perfectly fine with 75 ohms at R83.

Hah, you must be right. No reason to remove/bridge this resistor then. 75 ohm is pretty much a standard for video line termination.
There seems to be quite a bit of people who want to attempt it because of Satoshi's video though. Someone just Pmed me about it this morning.

The wierd part about those "gray pass trough pcb cables" are that they creat wierd resistance over each other. Dont know why? :S But replace them with better/thicker cable or sheilded if you can find that.

I do not really care enough about the SR3 being this perfect . I do not plan on replacing them unless they break.

I think tje SR3 will become my official on the field CRT tester. I gathered close to 30 CRT tvs in the last month from the massive moving period here in quebec, it is just insane they are everywhere. I will test them all and keep the best ones. The SR3 has both composite and sharp snes S-video out of the box. Composite is not stellar but I can take it outside in the yard and mess around with it with no fear of damaging a nice genuine retro console.

[Ace]

I'm assuming none of those CRTs are widescreen displays with HDMI inputs? If you have one of those TVs, KEEP IT! These things will put any LCD to shame.

[MaxWar]

I have 1 that is 4:3 HDCRT with hdmi, another HDCRT without HDMI but none that are widescreen.

Someone was giving a trinitron HD CRT 16:9 for free right next to where I live.
I saw the Add on Kijiji 4 hours after it was made. I called and the TV was already gone o_o

[Ace]

Holy shit! In Montreal, nobody wants CRTs no matter what they are. Listings for 16:9 HD CRTs with HDMI stay for quite a long time around here.

[MaxWar]

Even on the Free object categories?

Here, anything that is labeled "Free" is subjected to intense competition. There are people refreshing the pages every minute all day long.
I have listed some old beer bottles and a plastic artificial plant on the free categories and both were gone and carried away within 3 hours...

I know someone who listed a water bed for free. Phone rang 30 sec after she pressed the submit button...
Maybe that is only a quebec city thing...
Craiglist is not working in quebec city, I mean zero, there is no one using it. It is utterly dead. But kijiji is booming.

[Ace]

MaxWar, I need you to test something for me. It would seem light gun compatibility on the Genesis side of the Super Retro Trio is BROKEN; I can't get either the Konami Justifier or Sega Light Phaser working on the console. The Justifier is recognized, but unresponsive, and it seems to cause a HUGE electrical problem as with twin Justifiers and a controller plugged in, the VDP noise increases to insane levels (literally overpowering the audio!) and the video flickers like crazy. The Sega Light Phaser, though, simply does not work and I have no idea why. So I ask you, if you have either of those light guns, to test them on your Super Retro Trio so I can confirm whether Satoshi's Super Retro Trio has defective Genesis controller ports or all Super Retro Trios have broken Genesis and Master System light gun compatibility.

[MaxWar]

I have a SMS phaser but cannot get it to work on the SMS so that is not looking good so far :s
That might be my tv though, I could test it on a pvm maybe.

I also do not have Light gun games for the genesis, only the SMS. I could try using the Power base converter but that would add more variables in the testing.

Tell you what, I just finished my permanent diode install. I will clean up the install, take pictures and post it here so other people can do it.
Once that is done I will reassemble the SR3 and try using the power base converter and gun games with it. It is the best I can do, wish I could do more but cannot unless I buy more gear.

[MaxWar]

Ok so I tried finding the simplest way of putting a diode in series with the Genesis cart 5v rail on the SR3 and this is what I came up with. This will remove at least 80% of the VDP audio noise.

First I cut this trace here, This isolate the Cart 5v rail from the rest of the console.


Then By connecting a diode in this way you restore power to the cart slot and get rid of the noise.
Note that I am connected to the output of the power switch for the sega side and not the main 5v.
It is done in a way that the diode will only be powered when the genesis part of the retro trio is on. It will not be powered with SNES or NES are used.
If you connect the diode to the main 5v it is not good and the console will not work.
Also be careful to put the diode in the proper orientation. If you put it backward the game will not work.
Any diode of the 1N400X series should work, they are rated for 1 amp which is more than anough. I used a 1N4007.
Once again thanks to Ace for the idea of using a diode.

[Kasios]

Thanks for your tutorials are great!

[Ace]

I can confirm the Famicom Disk System runs fine on the Super Retro Trio, but as expansion audio is not mixed into the audio circuit, you will not hear the extra sound coming off the 2C33. I still need to run more tests with my NES and Famicom games and record them running on unmodified hardware, but once that's done, I will see how to add in expansion audio.

[Kasios]

For example the audio castlevania 3?

[Ace]

That's the VRC6 in Akumajou Densestu, but it's the same idea. Audio from the 2A03 gets passed into the cartridge, mixed, then output to the TV. The Super Retro Trio doesn't do this with any expansion audio hardware nor does it directly mix expansion audio like when you add a 47Kohm (should be 51Kohms, but, at least with a real VRC6, this needs to be 100Kohms) resistor to a Front-Loader NES to mix expansion audio with the 2A03's audio prior to the amp. The Famicom amplifies the sound from the 2A03 first, then sends it off to the cartridge slot to be mixed from inside the cartridge.

For the Super Retro Trio, direct mixing of expansion audio with the 2A03 is the ideal thing to do since the NES was never designed to have the 2A03's audio output fed into the cartridge and back out again, and the NES side of the Super Retro Trio has an NES cartridge slot, so it needs to follow this, otherwise if you try the Famicom method of expansion audio mixing, you would have to either short the audio input and output pins permanently or modify each individual NES game you have (and not all games can accept a mod like this, either, since later games are missing pins on the card edge). Neither option is a good idea, so the best of doing expansion audio mixing is to directly wire pin 46 (audio out) of a Famicom to NES converter to pins 54 and 55 (this is what the FC Twin and Gen-X use for expansion audio mixing, and they're the only two legal clones I've ever seen do this), then either directly mix the audio with that of the NOAC or add in a resistor to either the NOAC's output or the cartridge's output depending on which source is too loud on the Super Retro Trio's NES motherboard.