7800 + UAV = no color?

[+x=usr(1536)]

3 hours ago, -^CrossBow^- said:

For some odd reason the footprint for that IC that Ti provides for PCB design programs, has that large square off pin 10. That is marking one of the first input gates to the IC and is NOT for pin 1. There is actually a Dot that I added on the PCB board for pin1, but it gets covered up once you install the IC.

That gives a possible explanation for the boards with the upside-down IC - the pin 10 square could be mistaken for the pin 1 dot, and if assembling by hand, could easily result in installing the IC in the wrong orientation.

 

Not blaming the board or anyone building it; it's just a possibility.

[+-^CrossBow^-]

11 minutes ago, x=usr(1536) said:

That gives a possible explanation for the boards with the upside-down IC - the pin 10 square could be mistaken for the pin 1 dot, and if assembling by hand, could easily result in installing the IC in the wrong orientation.

 

Not blaming the board or anyone building it; it's just a possibility.

Oh I know that was part of the issue as TBA told me that. Again, that is how the footprint from Ti came across. I have a different footprint in use on my designs now that doesn't include that square. But these last few mounts that are giving black and white output doesn't seem to be due to the IC orientation since the pics I've been sent, the IC is in the correct position. I've a suspicion that one of the traces near the ICs didn't get made or isn't connected right in a batch of the boards that wasn't discovered. One of these boards is headed my way so I can try and remove the UAV from it and check it out in more detail. 

 

I'd like to know what is going on so that the issue can be found and reported back in detail to TBA.

 

[Nick15]

On 3/1/2024 at 10:33 AM, -^CrossBow^- said:

@Nick15 & @Erzak any updates on this?

 

 

It's been a busy last couple weeks for me, but I still intend on getting this worked out. That said, no updates from last time.... but it's been gnawing at the back of my head! I'll try to get back to this soon!! Thanks for your patience and help

E: Looks like other people have similar issues, so that's good to know that I'm not the only one with a similar issue. Hmmmm....!

Edited March 5 by Nick15

[+-^CrossBow^-]

@Erzak sent me his TBA purchased mount board and UAV setup for me to look at it. I pretty quickly found what I'm pretty sure is the issue as soon as I removed his UAV board to check. @Nick15 As you have everything apart already, refer back to my post where I noted points to test for continuity please.

 

I'm going to test the one I received now that I've 'corrected' it and verify it is good. If it is then I will update this post with what I found. But I'm suspecting that Nick's might be a similar issue.

 

*UPDATE* I've confirmed the issue with the one that was sent to me. Some of the pins on the IC chip on the mount board weren't soldered down making proper contact. I removed the IC, cleaned up the area, and resoldered it into place on this one and then tested it to confirm it is indeed working properly. Not sure if @Nick15's is the same issue but checking the continuity as I stated in an earlier post will confirm if that is a possible issue or not. I will relay this information to TBA so they can check for it on any others they might have and going forward on the ones they have made that they are selling.

 

Here is the IC after I got it soldered back down into place. It was quite a few of the pins on this side that weren't making contact.

 

Here is @Erzak's mount board wired up off a UAV I have installed in an older test 7800 here. The Maria Color wire is actually coming off the main board directly in this case to test the mount boards chroma fix is working properly.

 

And here is @RevEng's utility cart color test through s-video output on the same mount and UAV showing correct colors now.

[Nick15]

OH THANK HEAVEN IT'S WORKING NOW

I ended up moving the Maria line from the board (R16) directly to the UAV's Co.In line, and it's working now. Specifically, both Composite and S-Video are nice, clean and colorful. How frustratingly annoying.

 

22 hours ago, -^CrossBow^- said:

As you have everything apart already, refer back to my post where I noted points to test for continuity please.

Sure thing, I'll take a look at your suggestions and give you some results. I'll work on them now.

 

[+-^CrossBow^-]

18 minutes ago, Nick15 said:

OH THANK HEAVEN IT'S WORKING NOW

I ended up moving the Maria line from the board (R16) directly to the UAV's Co.In line, and it's working now. Specifically, both Composite and S-Video are nice, clean and colorful. How frustratingly annoying.

 

Sure thing, I'll take a look at your suggestions and give you some results. I'll work on them now.

 

Yes that is what @Erzak did before he sent his board to me to confirm the UAV was working properly. On @Erzak's board the issue was that the IC wasn't soldered down all the way from pins 9 - 16. So as a result the chroma timing wasn't active and thus no color signal was getting through. I just had to remove the IC and soldered it back into place to correct this. I've reached out to @MacRorie giving him more details along with what I use to check and make sure all of the connections on the IC are good so this can hopefully avoided in the future. 

[Nick15]

On 2/26/2024 at 6:17 AM, -^CrossBow^- said:

Another question and if this was answered already i apologize, but what about composite output? Is it black and white on composite output only for 7800 games also? 

 

The issue I was having was I was getting black-and-white for both Composite and S-video for 7800 games only. 2600 games were still in full color. Actually, exactly the same as @Erzak's chart. This was the case for both UAV + Mounting boards I bought.

 

On 2/26/2024 at 6:17 AM, -^CrossBow^- said:

Below is a quick diagram I just did to check if you have continuity between the points shown

For the board currently in my 7800: I got continuity between the yellow pins 3&4, the red Co.In pins, and.... well, I got continuity between the orange MC input and the PAD for Pin 9, but not Pin 9 on the CM0508 IC itself. Initially I was getting inconsistent continuity until I realized what parts I was touching. So I think that explains that one.

 

As for my other mounting board that started this mess for me: all three requested connections had proper continuity, so I'm unsure of why that one didn't work. Maybe there's a bad connection elsewhere that I'm missing, but at this point I'm just glad one of them is working. That's enough for me for now.

 

....

 

> -^CROSSBOW^-: "I've confirmed the issue with the one that was sent to me. Some of the pins on the IC chip on the mount board weren't soldered down making proper contact."

 

OK, yeah, that explains the overall issue then. I'll stick with the bypass for now, but at least I know what I'll need to do to fix it later on, or if I plan on using the now-spare UAV in another 7800.

 

Thanks a lot for your help and suggestions! Hopefully all this helps others out in the future as well. 😄😊

[Erzak]

On 3/9/2024 at 4:31 PM, Nick15 said:

 

OK, yeah, that explains the overall issue then. I'll stick with the bypass for now, but at least I know what I'll need to do to fix it later on, or if I plan on using the now-spare UAV in another 7800.

 

I'd recommend getting the IC hooked up properly, it seems to look better with the full mount board circuit hooked up.  

 

And the S-video output looks amazing!

Edited March 15 by Erzak