Neil
Well-Known Member
My Astra 111B is 2004 vintage & has the certificate "free of errors" . It is unused & yesterday at Marchwood YC Astro Nav lecture, it was found to be free of all errors !
My astra IIIb is of 2008 vintage and has a numbered certificate which, across all angles on the correction table, says "This instrument is free of errors for practical use"