CXA1145 Encoder brightness issue

[channelmaniac]

Hey p33pz!

Have any of you messed with the Sony CXA1145 video encoder? I'm using the bone stock circuit from the Sega Genesis, in fact I cut that section of PCB out and am using that.

It's connected to a Leningrad Spectrum clone and right now I have B&W composite output as I'm waiting on the 3.579545MHz color burst oscillator but it's very dim. Any thoughts on brightening up the output of that encode?

 

[daskrabs]

Does your circuit look like this per here?

 

[channelmaniac]

It's the Sega Genesis video circuit. I cut out that section of PCB and wired it in.

Unfortunately, this whole project has been scrapped. The Leningrad Spectrum clone puts out the proper horizontal sync when used with a 14.31818 crystal (4x color burst) but still outputs 50Hz vertical sync instead of 60. My Sony PVM and my Ikegami broadcast monitors pick that up as PAL video and none of the color comes through. In forced NTSC mode the picture just rolls.

Dang bast*rdized Russian knock-off clone design...

Not the first problem I've had with this computer. Timing of the chips is critical and I had to swap out different families of chips in different locations to get the 32nd column of text to appear and then more to get the 32nd column of color to work. It was odd seeing 31 columns of text and color... then 32 columns of text with only 31 columns of color. Now everything looks OK except some of the vertical segments of teeth are missing on the robot on the loading screen of PETSCII Robots and the video out on composite is stuck in B&W mode. To do color I have to use RGB, but don't have that in my 9" Ikegami monitors.

If any of y'all are in Houston for the Arcade Expo this weekend, my Spectrum clones and my COMIX-25 will be in the VCF Southwest booth connected to those Ikegami monitors. I won't be there though. I'm suffering through the afteraffects of 4x vaccine shots I got Monday evening. Still under the weather from those.