Discontinued products still get documentation and support updates when relevant. SeaLITHIUM VRC-100 Advanced Alternator Controller This product was discontinued in 2018 and superseded by the new VRC-200 Charge Reference Controller. Download Product Manual Download Installation Drawings

In July, I wrote about my experience with a homebrew twin-transducer ultrasonic antifouling system over 3 1/2 years on the aluminium sloop Nordkyn. It didn’t keep the hull clean once the antifouling reached past its prime, but the results were nevertheless very valuable as the system eradicated hard growth like barnacles on the hull, even in the […]

Starting Point I had hauled out the sloop Nordkyn for its less-than-annual bottom paint job. It was November, that year had been long, and so was getting the thin stringy weed clinging to the hull. In this condition, the boat is unusable. I was determined to make the effort last and so I generously sprayed […]

This article is part of a series dealing with building best-in-class lithium battery systems from bare cells, primarily for marine use, but a lot of this material finds relevance for low-voltage off-grid systems as well. This article discusses the protection of lithium battery banks in the context of marine installations. A previous article detailed the design […]

AIS, for Automated Identification System, is probably the most remarkable safety improvement in decades for small craft offshore. The little project presented here involved designing and building a simple, very low power alarm system to keep an AIS watch at sea. Collision Avoidance at Sea Avoiding undesirable encounters with ships in mid-ocean has always been a […]