I always admired KVH Datascope as the best handheld compass
in theory, but in practice, I have never seen one yet that did not have at least one segment of the LED display missing.
This is usually due to a defective zebra strip, which is normally easy to replace, but they are too expensive, even when defective and second hand, to justify pulling appart in the hope it can be made functional.
is still one of the most useful bits of gear
I have. It's a pity that a gimballed flux gate comass with some magnification (which was the design principal behind the KVH) and should have been a a much better product, failed, due to quality control/design issues.