Depending on the model you could also use the composite out (A600/1200) or the composite out of an A520 modulator.
As the previous poster said, SCART would be the ideal way if it were available on your TV (unlikely though).
Alternatively, there was a Amiga RGB > S-Video adapter project going on over at
EAB - you may want to check in there on the status of the project (ask Zetro).
In my experience even dblpal modes are often out of range on most monitors - just under 31kHz iirc.
Regards
Rich