Join Date: Aug 2006
Location: Arlington, VA
Thanked 13 Times in 11 Posts
Rep Power: 11
Both transmission and reception are usually adversely affected when operating in a marina. This is due to several factors, including all the other boats and structures which can deflect and/or absorb signals, and to the profusion of radio frequency interference (RFI) sources nearby.
The structures nearby (mainly other boats, particularly sailboats with metal masts and standing rigging, but also bridges, gangplanks, docks, pilings, shoreline features, etc.) will affect both the transmission of signals from your boat and the reception of incoming signals.
However, by far the worst problem in regard to reception of HF signals in a marina are the hundreds of RFI sources nearby, including those on your own boat, on the docks, and on other nearby boats. From a HF radio's point of view, marinas are very noisy locations!
Biggest offenders are digital devices (digital voltmeters, inverters, chargers) but also refrigerators, alternators, leakages from poor electrical connections, electric motors, computers, etc., etc. Tracking these down can be a real bear. And, often as not, the interference from other boats and from the docks...which you can't do much if anything about...is the real problem.
Nevertheless, if you track down the worst offenders on your own boat AND if you have a good installation AND if you are a competent radio operator you most certainly CAN make good radio contacts from your marina. This is true regardless of your location in the water or hauled out.
Hams like to pride themselves on being able to make successful contacts using low power under adverse conditions. Some low-power fanciers, "QRP enthusiasts", regularly make transAtlantic contacts using only 5 watts or less and wire antennas. I have done so for many years both from my boat and from land-based locations. This takes a bit more skill, but is something worth practicing against the time when you really might need to make a SSB contact under less than ideal conditions.