May 2015 – Salty John : The Blog

I had this to say on the subject after a wearisome beat along the south coast of Puerto Rico:

“By the time we reached Culebra, off the east coast of Puerto Rico, I was ready to give it all up and go sheep farming in the Great Karoo. Life had become one long, head-banging, salt encrusted bash into the teeth of a perpetual gale, off a rocky lee-shore, at night”.

“We had made our way from Boquerón in a series of night time hops taking in Guánica, Ponce, Salinas, Puerto Patillas and Isla Pineros. The wind was on the nose all the way and we often took two, three or more attempts at departure only to be driven back by the steep chop. We would “go for it” on an imagined lull and then endure a night of hell to reach the next harbour, an hour or two’s car ride along the coast. Such are the joys of sailing to weather, that thing which, very sensibly, gentlemen don’t do”.

So, it isn’t all rosy on the thorny path to windward. But, as my favourite philosopher, Anonymous, once said: What is hard to endure is sweet to recall.

If you have a top class radio and a top class antenna you’ll want the right type of cable in between or you won’t get the maximum performance from them – simple as that. For a cruising boat, selecting the right coax is as important as selecting the right anchor chain, so let us begin:

Coaxial cable for VHF radio and AIS is 50 ohm – your TV cable is 75 ohm so you can’t just use some coax left over from your satellite dish installation.

Marine coax needs to work in a hostile and constantly moving environment so both outer braid and centre conductor should be tinned copper to resist corrosion and the centre conductor must be stranded so it can bend without breaking. A good PVC jacket will protect the working bits and keep sunlight degradation at bay.

Transmission loss in the cable between antenna and radio (or AIS engine) is a significant factor, and if the cable is undersized and of inferior quality this loss will be unacceptably high. I think a leisure boat should aim to lose no more than 50% of the transmission strength between radio and antenna. In fact, the ISAAF, who manage offshore racing events, specify that there should be no more than 40% loss in the radio antenna cable.

A loss of 3 decibels (dB) halves the signal so you’ll want to restrict the line loss to no more than that. Signal loss in the cable, known as attenuation and measured in dB loss per unit of length, is determined by the size and construction of the conductor, the quality of the shielding and the operating frequency.

Good quality RG213 will lose about 33% of the signal strength in a 20m run, about 45% in a 30m run, so for very big boats it’s the way to go. However, RG213 (and its slightly lower spec but similarly stiff cousin, RG8U) is around 9.5 mm diameter so it’s heavy and doesn’t like to go around tight corners. It’s difficult to work with.

RG8X is nominally 6.5mm diameter, although actually about 6.0mm diameter unless it has a particularly thick outer jacket. This cable is much lighter and easier to work with than 9.5mm cable. Good quality RG8X will lose a little less than 50% of the signal in a 20m run.

You may also encounter RG58 cable; it sometimes comes with cheap aerials. It’s a 5mm cable and it’s OK for runs up to 6m but certainly not for masthead installations. It loses a whopping 65% of the signal in a 20m run. That means 15 watts of your 25 watts maximum power is lost just in the cable run.

So, make sure your cable is of marine quality with good shielding. For a cable run of up to about 20m or so use RG8X, for much longer runs you’ll need to wrestle with RG213/ RG8U. Don’t use RG58 for runs over 6m.

A penny in the antenna system is worth a pound in the radio, so don’t skimp on your antenna, cable and connectors if you want to unlock the full potential of your radio or AIS unit.

What do you do all day? When we were cruising full time this was a common question from land lubbers. The simple answer is “Whatever I like”; a more truthful answer would be “Whatever needs doing, and then whatever I like”.

As a cruiser I was always aware of the two modes in which we operated – on passage and in harbour. On passage you’re working full time to get the vessel from point A to point B efficiently and safely – you’ll be navigating, watch keeping, trimming.

In harbour it’s, if not necessarily party time, then at least a more relaxed atmosphere.

So, what do we do all day? Well, I don’t know what they get up to in the Med or the South Pacific but speaking for Florida, The Bahamas and the Caribbean it would go something like this:

I’d get up quite early, make a cup of tea and go for a stroll around deck, drinking in the beauty of my surroundings. I’d check that my neighbours and I were all anchored where we were the night before, wave to any other deck strollers and then pop below for a spot of breakfast. Over breakfast we’d decide on the day’s activity. There would usually be a maintenance list to work through and that would be tackled in the morning. We might head for shore and do some shopping if the need and the opportunity were both present. We’d have a spot of lunch around midday, catch up with a bit of admin – updating the log, writing or, these days, blogging – and then off to shore for a walk or beach activity or maybe some sightseeing.

Then back to the boat for shower time, sundowners and dinner. Or, perhaps, off to the local jump-up or socializing on another boat. In the busier anchorages there might even be an organized beach party.

And, always, there was the call of adventure. Where to next? When should we go? Check the weather, the charts, and the cruising guides. We’d be off again soon and that meant getting back into passage making mode, getting shipshape again.

It’s a tough life but someone has to do it.

If you regularly anchor you need to handle chain and if you handle chain you need an efficient anchor winch. You can choose to crank it by hand or have it driven by an electric motor, it can be capable of handling just chain or both rope and chain and it can be a capstan or a windlass.

Technically, on a windlass the axis of the shaft around which the drum or gypsy turns is horizontal; on a capstan it’s vertical. This distinction is rarely recognised these days and the terms are used interchangeably, so anchor winches are simply referred to as ‘vertical’ or ‘horizontal’ – just remember that it’s the axle on which the gypsy turns that is horizontal or vertical.

Whether you drive your winch manually or by an electric motor is a matter of personal choice influenced by the availability on board of sufficient electrical power or willing muscle.

On Adriana I had a magnificent bronze vertical winch from the Ideal Windlass Company. It was powered by an electric motor and had both rope drum and chain gypsy. On other boats I’ve had a horizontal manual Goiot winch and a horizontal powered Muir – they all did their job well.

A vertical winch with its motor mounted under the deck takes up a little less space on the foredeck where space may be at a premium. On horizontal windlasses the motor and gearbox are usually mounted on deck, integral with the winch.

Another feature of a vertical winch is that the chain exits the gypsy horizontally and travels a short distance before entering the naval pipe. The naval pipe has its opening oriented horizontally and pointing away from the bow so it is an inherently more water resistant arrangement than the vertical opening into which the chain from a horizontal windlass must drop. But these are fine differences and I’ve used both configurations successfully.

Whatever the configuration of the winch you choose, it is vital that the chain gypsy is correctly mated to the chain. Calibrated short link chain is what’s used on an anchor winch but there are several sub-types, each with a slight difference in chain link dimensions, so make sure you have the right chain for your gypsy. Mismatched chain and gypsy is a formula for frustration, and possibly worse.

Happy anchoring!

There’s a new generation of fixed DSC/VHF radios incorporating an AIS receiver that are seriously worth considering.

The clever bit is that they combine excellent radio performance and AIS receiver functions in the same compact unit. An internal splitter shares the radio and AIS reception from a single VHF antenna.

The not quite so clever bit is that the display for the AIS information is really too small to be practical in areas of high ship traffic, which is when you want it. However, what you can do is connect the AIS output to an external plotter or dedicated AIS display.

Remember that you’re depending on a single antenna system, so it better be a good one – obviously that’s going to be a Metz Manta with top quality coaxial cable. And it’s always a good idea to carry a spare antenna with a means of deploying it in case you lose the main antenna through a dismasting or other emergency.

Over.