[Rhodes22-list] Compass

[Steve Alm]

The previous owner of my boat had a removable six inch high board that sat
across the companionway.  On it he mounted a compass AND an auxiliary
speaker for the radio.  An ill-fated feat of engineering since the compass's
proximity to the speaker (magnet) rendered the compass useless right from
the get go. Needless to say, I've never used the thing and it's been stored
in my garage all these years.  But I pulled it out the other day and removed
the speaker.  The compass now seems to point north OK but I'm wondering if
it's damaged or compromised by sitting next to the magnet all this time.
It's a Ritchie B-80.  It has what I assume to be a calibration screw on the
front, but I don't know how to calibrate or test a compass.  Any advice?

Thanks,

Slim