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

[quote=Casablanca]

Jeff, sorry but my reply exactly fits the symptoms!

[/quote]

 

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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Sorry to bump an old thread,

Sorry to bump an old thread, but another long shot: assuming the IIc Color Monitor is like the IIe Platinum Color Monitor (I think it is?) it can be modified to display standard NTSC devices in color, which then would make a IIe Plat/IIc display in black and white.

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Joudan wrote:Sorry to bump an
Joudan wrote:

Sorry to bump an old thread, but another long shot: assuming the IIc Color Monitor is like the IIe Platinum Color Monitor (I think it is?) it can be modified to display standard NTSC devices in color, which then would make a IIe Plat/IIc display in black and white.

Indeed there is a button to press for BW monocrome on the Colour Monitor //c just as with the //e veriom.

 

IDK if this was a question or a statement. I you need help, LMK.

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Same with Euroepan Apple IIc

I have the same problem than the one explained by the OP. At the moment I connected  my Apple IIc (612-0128-A motherboard and 4X ROM) only to a TV. This TV properly shows colour using my Apple IIe and a couple or retrocomputers, but when I connect the Apple IIc I only get a B&W image. I'll try to find another monitor/TV where to connect the Apple IIc.

 

Meanwhile, I guess that my motherboard is a PAL version, not an NTSC one. but I did'nt find how to check this. Motherboard reference do not helps. The Apple IIc Technical Reference manual only refers to the NTSC board, not the PAL. Where can I found this information?

 

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Well, finally I catched the

Well, finally I catched the picture:

 

In the Apple IIc european version (PAL) the composite video output delivers only B&W signal and you need to connect an adapator to the monitor output to get RGB signal (colour).

There are several adpaters (Apple PAL modulator, Le Chat Mauve) but is almost impossible to find one. A2heaven has also a modern adapter but is expensive ans also out of stock so, there are not many options.. .

 

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