Apple IIc displays B&W on monitor but color on TV but monitor displays color when connected to other devices.

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Apple IIc displays B&W on monitor but color on TV but monitor displays color when connected to other devices.

Hello so I have an Apple IIc, Model No. A2S4000 & a Color Monitor IIC, Model No. A2M4043

For some reason when I connect the computer to the monitor it only displays Black & White. I connected the computer to several TV sets & they all display in color just fine. I then tried connecting the monitor to a Sega Genesis & the monitor & it displayed color just fine. The TV & Genesis I used were NTSC, the Apple IIc & monitor I assume are NTSC as well but I do not know for sure.

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Check if your apple 2c

Check if your apple 2c motherboard is not from the European PAL version of 2c which also outputs 50Hz instead of 60Hz framerate.  

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Check that the color intensity control ...

Check that the color intensity control isn't set to minimum (all the way counter-clockwise) on the monitor.

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The previous replies don't fit your symptoms

The previous replies don't fit your symptoms since both the //c and monitor have been shown to be "mostly" working. 

That leaves just some incompatibiity between the two. And since they're both Apple products meant to work together I presume something must be out of spec.

 

Things to check:

1. Try a different composite RCA cable. Duh.

2. Check the video level coming out of the //c. (Might be low)

3. Check the color killer circuit. (Might be putting out a weak color burst)

 

The last two will require a good scope.

 

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Jeff, sorry but my reply

Jeff, sorry but my reply exactly fits the symptoms!

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Casablanca wrote:Jeff, sorry

Casablanca wrote:

Jeff, sorry but my reply exactly fits the symptoms!

 

So a PAL //c would display perfect color on an NTSC TV?

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It would display in

It would display in monochrome. As is the case of the topic starter.

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Except that the original post

Except that the original post reads. "I connected the computer to several TV sets & they all display in color just fine. "

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How would I go about checking

How would I go about checking if the motherboard is PAL?
https://imgur.com/a/Hl2L5zP
 

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Motherboard is NTSC for sure.

Motherboard is NTSC for sure. 14.3 MHz crystal is a dead giveaway.

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So what could it be? The

So what could it be? The monitor displays color not matter what I hook up to it & the IIc displays on color on old CRTs, new flat screens but just not ont he monitor.

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Long shot... but try

Long shot... but try pushing the "white only" button a bunch of times.

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