5200 dark screen

[ulao]

So I have bought 4 Atari console recently.

 

2600, video was dark but I thought maybe this was how it was. I modded it to composite and it was the same.

7800, very nice video and bright. Modded and was the same

7800 (another)  left as rf nice and bright

5200, modded (never tested rf) dark video.

 

So, I sold the 2600 since I have a 7800, and now I'm hoping to fix my 5200 so I can actually see it.  I read this.

 

 

but there were no details given. Most often times ( not always) the silk print remains the same, but no one offered the resister number. So I'm not sure what resister to remove (if that is even the issue) on the 5200. I could have compared schematics...  Does anyone have a clue what really makes the image so dark? I would have suspected a leaking cap but it does not look like there are many caps on these boards. Should I use an op-amp and try to boost the voltage closer to 1 volt? Should I put a scope on it and see what the single says?

 

 

 

 

 

 

 

[+-^CrossBow^-]

The resistor in question on that thread I believe was in talking about a 75Ω resistor that I've seen bridged on the RCA jack for composite or on the video out side of the mod board bridged between the video out and ground. I believe this is done to try and better match the impedance or to prevent the image from being too bright and washed out on CRTs but ends up looking too dark in many cases. I was able to remove the added in resistor on one install but in most cases, the consoles sent to me with this issue with one of the cheaper composite mod boards...end up getting a UAV to replace it all out.

 

And yes the RF output can look quite dark especially on modern displays. I see this will almost all of my Atari consoles through RF on my modern displays although they look find on a CRT.