Several of us at Heybridge Basin had a chap from S.I.R.S come down and check us over. Swing only to produce a deviation card each, no corrections needed. He was very good, not expensive.
Good day for risking a lynching. Does swinging the compass matter? With GPS you know your course accurately and course for where you want to get to. If the course in wrong the GPS tells you again accurately.
My Plastimo Conest is very difficult to read to better than 10 degrees at the best of times and far worse in a seaway. In any case you can use the GPS to help calibrate the compass if you are in current free water.
I am actually with you all the way 'cos I'm not one of the if you can't navigate by stars and bits of string you're not a real sailor brigade but....
Going on a 3,000nm trip in May and fancy reading compass as well as GPS...
Something I would just 'like to have sorted'...
Boat's 15 years old now and seen lots of new electrical kit so want to be sure I'm not waaaaaaaay out!!!
Do have quad redundancy for GPS curently (2 fixed 2 portable) so not unduly worried about power failure.....and anyway it's a motor boat so no power means no movement anyway!!!!