Pioneer Laseractive LD/Mega LD display issues

I scored a Pioneer Laseractive yesterday with a Sega PAC. The Genesis/SegaCD side of things works great but when I popped in Pyramid Patrol I got audio but no video. When the menu came up to start the game it was in black and white and the graphics looked like they were being pulled apart but coherent enough to see what I was looking at.

Game starts and there is absolutely nothing in the background and all sprites were in black and white with the same horizontal tearing going on. Audio is great though!

Silpheed plays fine. Laserdiscs themselves only play the audio leading me to believe there might be some sort of partial laser failure if that is even possible. Maybe something to decode the analog video is shot?

 

It is quite possible, laserdisc assemblies usually have more discreet and/or complex optics, that is to compensate for the looser tolerances, every LD I have ever seen had noticeable mild warping. Additionally since the mass of the LD is far larger than a CD the spindle motor is stronger too. I'd look at the Spindle motor, tracking circuit and the laser in that order.

 

Play normal videodiscs and see if they play properly...

 

Nope. You get audio but absolutely no video. I can understand why the background video won't play on Pyramid Patrol and why the audio works because of this but I don't understand why the sprites are distorted. Then again I have no idea what handles the sprite overlay for Mega LD titles.


^what all of the graphics basically look like.

 

Replace the electrolytic capacitors.

 

That is my first and only thought so far but it seems too obvious and too easy but I've got nowhere else to start. If I want this thing to see another 20 years I'll have to recap it anyway.

Service manual for anyone interested:
http://cyberroach.com/new_laseractive_pics/misc/clda100_repair/servicemanual.htm

 

One board completely recapped short of 2. 79 capacitors replaced over 3 hours. No change.

Got at least four other boards with capacitors left.

 

While recapping, make sure you inspect for corrosion damage or chips with cracked joints. Generic common sense repair hint.

 

I didn't see any thankfully. The electrolytics hadn't gotten a chance to do any real damage and there are no surface mounted capacitors anywhere inside the Laseractive that I could find - mainly ICs.

The Sega PAC will be recapped as soon as the parts come in as that sucker is almost pure surface mounted horror.

 

I meant recap the PAC

 

Bump !

It's not the PAC, the issue come from video assy board. There is a problem with LD video decoding signal.

 

Problem with the ADC, Video controller or DAC? Would that explain the missing backgrounds, tearing and b/w picture. From the schematics it looks like it only outputs CVBS.

 

Video game graphics are superimposed atop the output from the large top board (Laser Disc video board) at the tiny board at the back with the BA7230 chip. The tiny board takes RGB from the PACs and CVBS from the Laser Disc video board, mixing them and otputting to the RCA jacks.

 

I think it's the video controler or some active componment around it. b/w picture appear only when a LD is played with PAC playing controls displayed on screen. Without PAC, and with no playing controls there is a black screen with sound. Plus, with PAC's playing controls, image is out of syncro (PAC's controls in black and white and no LD image).

When the Laseractive is powered up without pac, OSD is displayed correctly. During play, OSD is out of sync.

I must check references signals around video encoding part with an oscilloscope. But It's certainly not the video boards at the back of Laseractive.