After repairing the PSU and the shorts on the mainboard, everything works fine except some strange misbehaving of the composite video output. First I've had it connected to an 9 inch IIc monochrome monitor, the color killer switch on the PAL mainboard was switched to MONO. The picture quality wasn't great at all out of the IIe compared to the output of my IIc connected to the same monitor - but was getting better after a few minutes of warming up. So I can rule out the monitor itself.
Next I've hooked up the IIe to an LCD TV over composite-in. With the color killer switch set to MONO, it looks like this:
As you can see, the signal seems to pulse vertical, but not horizontal. If I set the the switch to "COLOUR", the picture on the LCD TV gets more stable (in Text-Mode), it also displays the correct colors.
This is the Board in question:
Reading one of speedG's threads troubleshooting a familiar problem on the same board, I made sure that all correct PAL Roms are beeing used.
The pulsing and the "warming up" is strange, don't think it's an IC. The schematic 8.6 in "Understanding the Apple IIe" is showing the C124 and the VR63/VR64 responsible for the luma (Y-RY+BY) signal for color? But if the switch is on MONO, it is bypassed? Is this correct?
If I set the switch to MONO and run a screen diagnostic with color patterns, it shows some colors but the whole picture is getting totally out of whack.
Has someone encountered something similiar?
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