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Re: Can I use a US motherboard in my European Apple IIe?

Michael J. Mahon wrote:

Knut replied:



I did some testing on that. This particular monitor (IBM CGA 5153)
accepts composite sync on pin 8 (hsync). I used the LM1881 to make a
vertical sync but applying this doesn't make any difference. The LM1881
also creates a cleaned composite sync and as well, applying this also
doesn't make any difference. It is so that it can almost hold the
picture so I think it is the 50Hz 60Hz difference that is the matter.



In that case, I agree.

There is almost certainly a control inside the monitor to adjust
the vertical frequency (vertical hold), and, with the control, I'm
sure that 50Hz is within lock range.

But it is not too surprising that 50Hz is outside the unadjusted
lock range.
There are two controls on the back of this CGA monitor. One is vertical hold and the other is vertical size. If I turn it to one end it can sometimes hold for a moment. Do you think that it might be further adjustment inside (I don't have any docs for this monitor, yet). I had actually assumed without looking inside that this would be all the controls for vertical there is. 

Knut