Hey Kez a hunk of string with a weight on the bottom will work with all those limitations...
Kez, I have an older Sitex that I do not use. I think it is the Neptune model. Not a large unit and it is black & white. I don't want to sell it cause it is not totally user friendly in putting in waypoints (that's why I took it off the boat), but it will show you what you need to know. The last I used it it worked just fine. It's your's for the asking. Comes with the c-map charting (older map). Don't think I have the book for it anymore but can show you the general use or maybe you can get the documentation on line. I plugged it in earlier this year to check something out on it and it worked fine then. Let me know if you want it.
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