Please Help: 2600 Junior PAL + UAV Rev.D

[0078265317]

On 2/12/2021 at 4:51 AM, TheMontezuma said:

 

@tf_hh @Bryan

Do you know if cd4050 wiring in NTSC and PAL 2600jr consoles is the same?

If the UAV is only designed to work with the NTSC 2600jr, it would explain the wrong colors...

 

Any luck gettin g the right colors yet?

[radventure]

3 hours ago, alex_79 said:

I had some pictures of one of my Jr board on my PC (PAL-B, board CO21503, rev. F1). I've highlighted the traces going  from the luma and Sync TIA pins to the CD4050, and they match J.Sobola's schematic:

 

board (top)

 

bord (bottom)

 

 

You might be able to fix the mod with minor modifications, by removing all the jumper plugs and soldering short pieces of wire to connect the pins as in this picture.

 

 

There's still the problem that with the CD4050 removed, the gate in the CPU reset circuit (circled in blue in the schematic) is missing. Since your console is still working without it, I guess it's not strictly necessary, but if it was me I'd follow @DrVenkman suggestion and I would remove the mod board, reinstall the CD4050, and then simply connect the mod using wires to the needed signals (those pullup resistors connected to the TIA pins are perfect for this).

 

Verify that your board matches the one shown here by checking continuity between pins marked with the same colors. If it differs trace it to find the right spots where to pick the signals.

Note that I'm not familiar with the UAV board as I never installed one myself, so use these info at your own risk!

 

This is great information and very helpful - thank you @alex_79 .

 

I'll definitely reinstall the CD4050 as @DrVenkman has recommended. 

 

My board is the plug in style, but i'll see what i can do to desolder the headers from it as there's no a lot of spare room in a Jr case. All going well it might be a v1 upgrade. Bare board(s) will be ordered on proving this successful, for swapping in (i have other Jr's that could use svideo). Hopefully i'll get a chance this weekend (early Friday morning here right now) - I'll post updates back when i do.

[radventure]

....CD4050 reinstalled, continuity from TIA checked - everything as expected, per your info @alex_79 (thank you again!).

 

I've tried some removal of header / jumper pins from my existing UAV (Plug in) with no decent progress for the effort (i only have braid, i'm also concerned with the heat i'm pouring into a tiny board). I'm going to order a basic UAV and continue work with that i think.

[Wizzard]

On 2/12/2021 at 4:35 PM, tf_hh said:

Speaking about the 2600 consoles I´ve been radical and remove all non-necessary parts in the video and audio circuit, especially the transformatio-to-HF circuit for audio carrier (RF usage). This results in massively less noise at the whole system. To make the correct connections, I test from TIA to the resistors etc. they might be correct the continuity and use then the pads for grabbing the signals - to prevent soldering directly at the chip´s pins. It´s only five signals, this will take a minute or two.

I also wanted to remove all the unused components from my AV modded Ataris, but could not find the answer which are safe to remove.

 

I would like to ask also about the PAL/NTSC issues on this mod or other RGB mods. Does it turn Atari to be both PAL and NTSC compatible? I read that RGB output does not know PAL or NTSC. Is it true?

[+tf_hh]

On 3/8/2021 at 7:23 PM, Wizzard said:

I also wanted to remove all the unused components from my AV modded Ataris, but could not find the answer which are safe to remove.

 

I can sent some pictures at the weekend which parts can be easily removed (2600 junior).

 

Quote

I would like to ask also about the PAL/NTSC issues on this mod or other RGB mods. Does it turn Atari to be both PAL and NTSC compatible? I read that RGB output does not know PAL or NTSC. Is it true?

 

I didn´t follow all posts, sorry - not possible. But UAV works with NTSC and PAL - 100% sure. But there are differences due to different TIA pinouts. The NTSC TIA uses some other pins for Color, Luminance and Synchronisation signals like the PAL TIA. The PAL TIA needs an additional frequency of 4,43 MHz for the PAL-burst color carrier. NTSC circuits use the system clock of 3,58 MHz simply. So you can´t easily change a 2600 in NTSC to PAL and vice versa without some modding.

 

[TheMontezuma]

On 2/11/2021 at 12:52 PM, radventure said:

@TheMontezuma Did this ever get a resolution? I’ve just finished fitting a rev d UAV + IAB into a PAL 2600 jr (well, I still have to work out top case refitting, but it’s useable)

 

It is exhibiting the same colour issues.... while the picture is sharp, colour is pretty much on par with the screenshots in this thread. Colour pot adjustment has been performed.

 

My UAV board isn’t getting hot or anything though. I’m using svideo output to a retrotink mini, connected to a Samsung Syncmaster LCD. 

Today I finally found time for my 2600 and followed new instructions in this thread.

I removed configuration jumpers from UAV and directly soldered the signals.

Unfortunately my UAV is directly soldered in place of CD4050, but I decided to keep it here.

Thanks to everybody, especially to @alex_79

 

 

Edited March 13, 2021 by TheMontezuma

[radventure]

Finally got to ordering a Basic board..... shipping is killing me ?

[+tf_hh]

On 3/10/2021 at 9:37 AM, tf_hh said:

I can sent some pictures at the weekend which parts can be easily removed (2600 junior).

 

Here are two pictures, where is easily to see which parts can be removed to cut the video and audio amplification from the signals to feed UAV:

 

 

 

The single wire is for the "COLOR IN" input from UAV.

 

[Wizzard]

1 hour ago, tf_hh said:

Here are two pictures, where is easily to see which parts can be removed to cut the video and audio amplification from the signals to feed UAV:

 

The single wire is for the "COLOR IN" input from UAV.

Thank you very much. I do not have UAV yet, so by the chance do you know which parts are safe to remove just for ordinary AV mod?

[radventure]

thank you @tf_hh - this additional info is excellent. Gotta keep these Jr's alive and performing well.