2 issues with Genesis VA7. please help.

[infidelity]

1. I have the Mega Everdrive X7, and on my VA2 Genesis I've had no problem playing titles.

However, my VA7, which had the TMSS at boot up, some games will boot, some will freeze or crash? Sonic 1, I can't get past the SEGA logo. Aladdin, I can't get past the SEGA logo where Genie shoots up, it'll just freeze. And certain games will randomly lock up during game play.

Is this an issue with my everdrive, or the system? (Yes, connectors are clean, and I'm using the original power supply)

2. I use scart for video, which means I need the headphone jack for stereo audio. The headphone jack does not output any audio at all. I've looked all over the internet, but couldn't find anything exactly like my issue. Does anyone know how to fix no audio coming from the headphone jack on a VA7?

Thanks!

[FinalBaton]

Since you have audio issues with your VA7 anyway, you should take the opportunity to install a MegaAmp in it

It's gonna sound sooooooo much nicer. so worth it IMO

[infidelity]

Ok, but will that device resolve the fact that currently there is no output of audio from he headphone jack?

[FinalBaton]

can't say. I dunno if it replaces the headphone pre-amp or not...

[ApolloBoy]

can't say. I dunno if it replaces the headphone pre-amp or not...

The Mega Amp 2.0 includes a headphone amp so yes, that should fix the problem.

[infidelity]

Where can I purchase the Mega Amp 2.0?

[infidelity]

Bump

[FinalBaton]

You gotta contact forum member Ace over at sega-16.com.
There's a link under his avatar to contact him via Skype.

Here's the thread about the Mega-Amp 2.0 started by Ace himself :
http://www.sega-16.com/forum/showthread ... -0-is-here!

[mvsfan]

Or you could just get A VA6.8 or earlier Genesis that doesnt have audio issues.

All of the model 1s except the Va7 and to some extent, Va2 dont have them.

[Syntax]

http://www.sega-16.com/forum/showthread ... p-2-0-Mini

Helder is selling some at the moment.
Not sure if they fixed the mono circuit or not, ace stuffed up with how it mixes into the second amp, needs 4 resistors added

[infidelity]

I swapped the issued va7, with another va7, and graphically it's an improvement over my broken va2, plus the headphone jack on this other va7 is working correctly.

But the VA7 sound is so atrocious. It's confusing for me on what kind of mega amp to purchase, because I see pro, and mini. I want to be able to still have my sound coming from the headphone jack, and I want my 32x & Sega cd (if I get one) to sound correctly.

What should I do?

[zeruel85]

I swapped the issued va7, with another va7, and graphically it's an improvement over my broken va2, plus the headphone jack on this other va7 is working correctly.

But the VA7 sound is so atrocious. It's confusing for me on what kind of mega amp to purchase, because I see pro, and mini. I want to be able to still have my sound coming from the headphone jack, and I want my 32x & Sega cd (if I get one) to sound correctly.

What should I do?

The difference between Pro and Mini are explained in the official topic, written by Ace:
http://www.sega-16.com/forum/showthread ... -0-is-here!

Maybe in the future I will reorder some Mega Amp Pro v2.0, if you are interested.
You can see a pic of my PCB here:

Spoiler

Or if you prefer the Mini version, I released the PCB projects for free, on OSH Park:
https://oshpark.com/shared_projects/cLhLtWV3

[Syntax]

I'll buy a pro 2.0 if you make another run.

[infidelity]

I purchased the 2.0 mini from Helder. But I'm very confused on part of the installation.

SN76489, on the 2.0 mini has 1 spot to solder to. But, on the diagram for my VA7, it shows 4 spots to solder to? Am I supposed to have 4 wires coming from the 2.0 mini, or am I simply able to just choose any of the 4 spots on my VA7 to solder to?

[zeruel85]

I purchased the 2.0 mini from Helder. But I'm very confused on part of the installation.

SN76489, on the 2.0 mini has 1 spot to solder to. But, on the diagram for my VA7, it shows 4 spots to solder to? Am I supposed to have 4 wires coming from the 2.0 mini, or am I simply able to just choose any of the 4 spots on my VA7 to solder to?

Any of your choice (only 1 wire is needed).

[infidelity]

OK great, thanks.

Also, for headphone jack usage. The mini has solder pads called "Left" "Right" so are those for the headphone jack?

And the diagram doesn't show exactly where to solder the wires to the pins on the VA7, just gives numbers of the pins. Could anyone elaborate further on that specific installation?

[zeruel85]

OK great, thanks.

Also, for headphone jack usage. The mini has solder pads called "Left" "Right" so are those for the headphone jack?

And the diagram doesn't show exactly where to solder the wires to the pins on the VA7, just gives numbers of the pins. Could anyone elaborate further on that specific installation?

Doesn't the reseller provide any instructions? I don't know how it's built his PCB, it's better if you ask to him, IMHO.

[infidelity]

Haven't heard from, been trying to contact him that I made a purchase to his PayPal. I guess I'll just wait till he replys. Sorry for asking here, I assumed others may have used his product.

[mvsfan]

Yeah the left and right are for the headphone jack.

If you do use the headphone jack, you might want to cut the traces going into the volume slider, and solder your output from the mega amp, to the left and right on the volume slider, that way it will still work with your headphone jack.

I did that on my va7. my mega amp Is OLD though. ive had it a long time i just might re do it with the pro version.

[infidelity]

I'm not sure if I'd want to solder right onto the volume slider. Is there anyone that could possibly shed some light, on where these pins are for headphone jack output?

I've tried to contact Helder, but I've gotten no response. But what's odd, is that he mailed out the board, I got it today.

[Syntax]

Can you post a pic of the board, interested to see what they did to fix mono mixing clipping.

[infidelity]

http://www.sega-16.com/forum/showthread ... p-2-0-Mini

[zeruel85]

Ceramic caps for AC coupling... I'm not a big fan of that.

[Syntax]

http://www.sega-16.com/forum/showthread ... p-2-0-Mini

That's an old picture, did your board look different/modified?

[infidelity]

I haven't examined it, but I do have it set aside, I won't be able to get to it till after work tonight.

I have 2 things to mention. 1 is a realization, the 2nd is a question.

1: I think I figured out the heaphone jack wiring issue. I'll upload 2 pics of my VA7 board, which will show the factory markings, as well as my doodling describing the locations.

Top
https://imgur.com/a/ceyFC
Bottom
https://imgur.com/a/6dTpb

Am I safe to assume, that the left/right wires from the mega amp, are to go to those 2 spots, which I can simply solder the wires to the bottom of the motherboard?

2: I'm a little confused with the GND & 5V installation for the VA7. The diagram shows the lettering GND & 5v next to 2 spots. So I'm assuming the 2 wires go to those spots. However, the other ends of the 2 spots, he says to create a solder bridge.

His diagram
https://imgur.com/a/0zRhK
My markings
https://imgur.com/a/cfQAF

Are my markings correctly understanding his directions?

[Syntax]

Dear god no. If you put a wire there you are bridging 5v and ground.

The top is clearly labelled ground and the bottom 5v.

you have to remove the resistors, put solder where the resistors were and 5v and ground wires to the correct spot.

An easy way to do both at once is remove the resistors and bridge the gap with the wire.

[infidelity]

Thank you for that explanation! It confused me alot, and especially since he took the time to draw red boxes over items that need to be removed. So the GND/5V really threw me for a loop.

With that resolved, is my idea on the headphone jack correct?

[zeruel85]

You have some friendly test points near the connector.

[infidelity]

Well, after everyone's guidance with this thread, I went ahead and installed the 2.0 mini into my VA7, and wow, that really cleaned the audio up on this machine!

I kept the motherboard accessible during my tests, so I could have access to the 2 filtered/unfiltered switches. The unfiltered sounded amazing, never heard a Genesis sound that crisp and clean, but sometimes it seemed a bit to sharp for certain tones, so I went back to filtered.

What I've also noticed, and idk if it's from my choices of where I soldered the 2 wires, or if this is just the way it's supposed to be, but I lost the ability to adjust the volume with the headphone jack. It's just full blast. Again that's my main audio output, since I'm using a scart cable with a combined 3.5mm stereo jack. So idk if I was supposed to solder the wires elsewhere? Either way, I can live with it.

[Syntax]

How does mono sound?