N64 RGB amp help

[ebeb]

I've never soldered before, so forgive me if this is an obvious question.
I purchased an adapter board to use with my THS7314 amp, but I'm unsure which pads connect to which holes on the board, and which direction I should solder the amp (if it matters).

Here's my adapter board:


I'm using the side of the board on the right.
Thanks!

[darcagn]

There should be a notch on the THS7314 chip that indicates which side of the chip has pin 1.

Then make sure that when you solder the chip to the adapter board, that pin 1 is connected to the hole that is labeled '1'.



See the notch on pin one?

The three channel ins/outs are for the R, G, and B lines to be amplified. VS+ is your 5V power and GND is the ground.

[killradio]

of course it matters

maybe that should help you

[ebeb]

Thanks for the help, darcagn and killradio!

Another question, hopefully the last. I don't see a notch on the chip indicating the position of pin one. The only identifying mark I see on the chip is a bar on the left side. Does that tell me where pin 1 is?

[CkRtech]

Hey ebeb,

The bar also represents the side of the chip where the 1st pin is. If you hold the chip so that the bar is at the "top" of the chip, pin 1 will be in the top left corner.

[ebeb]

Alright, thanks for the info!

So I soldered the amp to the adapter board, and soldered wires to R8, R9, R10 and the multiout port. The result is I get very faint video with no color when using SCART, with no color. When using composite, the video is heavily tinted blue.

After desoldering the wires, composite video works fine again. So then, I soldered new wires onto C124, C125, and C126. Now, I get very clear greyscale video. Composite video has color, but it's darker.

I don't see any contacts or joints touching on the mainboard or the amp's board. I don't know if it matters, but the capacitor is touching the wires for the ground and power, as well as the holes. Any ideas?

(Blurry) photo of amp:

http://i.imgur.com/IaSUM0F.jpg?1

[ebeb]

I ended up just making another amp circuit using my backup amp.
The result this time is video on SCART that is missing blue. When I solder C126 directly to the multiout, however, it works.
I've checked the joints on the amp board with a multimeter. What's really odd is that there is a voltage carried from blue out on the amp to the multiout, but there's still no blue color. I'm at a loss.

[Bax]

I ended up just making another amp circuit using my backup amp.
The result this time is video on SCART that is missing blue. When I solder C126 directly to the multiout, however, it works.
I've checked the joints on the amp board with a multimeter. What's really odd is that there is a voltage carried from blue out on the amp to the multiout, but there's still no blue color. I'm at a loss.

I'd resolder the input & output legs on the THS7314 for blue channel just to be sure.

Also, I can't tell from the picture but unless you are using red colored wires only, then you have them mixed up on the outputs. The wires should go straight through.

[ebeb]

I ended up just making another amp circuit using my backup amp.
The result this time is video on SCART that is missing blue. When I solder C126 directly to the multiout, however, it works.
I've checked the joints on the amp board with a multimeter. What's really odd is that there is a voltage carried from blue out on the amp to the multiout, but there's still no blue color. I'm at a loss.

I'd resolder the input & output legs on the THS7314 for blue channel just to be sure.

Also, I can't tell from the picture but unless you are using red colored wires only, then you have them mixed up on the outputs. The wires should go straight through.

I don't have any blue wire, so I used red for both red and blue in/out.

When you say the wire should go straight through, do you mean all the way through the hole?

[eightbitminiboss]

He means like Red in to Red out. Like this:

Forgive the sloppy job, I was in a rush...

[ebeb]

Ok, that's what I did.
Well, I tested composite video, and now it also lacks blue. What could cause that?

[eightbitminiboss]

I'd start testing your points then with a multimeter. The lack of blue on your display could just be that it's not wired.

[ebeb]

I'd start testing your points then with a multimeter. The lack of blue on your display could just be that it's not wired.

I desoldered all the wires from the N64 mainboard; there's still no blue on composite.

[eightbitminiboss]

I'd start testing your points then with a multimeter. The lack of blue on your display could just be that it's not wired.

I desoldered all the wires from the N64 mainboard; there's still no blue on composite.

Then something got fried.

[CkRtech]

I desoldered all the wires from the N64 mainboard; there's still no blue on composite.

The only thing I can think of is that you have some sort of solder bridge or disconnect on the resistors under the board that you used for your solder points. I can't recall the chip setup of the N64 as far as video encoding (I soldered directly to the RGB output of the chip back when I did mine) but if those resistors are responsible for pushing R, G, and B to an encoder and you disconnected or grounded out the blue one...that would kill blue everywhere, basically.

[ebeb]

After removing all of the solder I put on the back of the video chips (C124, R8), composite works fine again.
What would be the easiest way to solder to the video chip? I'm afraid I'm close to burning some of the traces on the board, especially near the multiout.

[CkRtech]

My concern about you soldering directly to the video chip is the fact that you started this thread with "I have never soldered before." Soldering to actual points on the bottom of the board should be easier than soldering directly to the chip because you don't have to worry about a solder bridge crossing multiple legs of the chip.

What guide are you using for this?

[ebeb]

What guide are you using for this?

I'm using this: http://www.mmmonkey.co.uk/ntsc-nintendo-64-rgb/

[ebeb]

Finally got it working. RGB looks great; I never realized how blue Mario's eyes are.
Thanks so much for the help, everyone! Hopefully soldering won't be as arduous now.

[CkRtech]

Good job!

[eightbitminiboss]

Glad you worked it out.

[blizzz]

This thread is like a description of all my solder attempts

Good to hear that it worked out in the end!