March 2 , 2002
Choices in Electronics

THETA VOLANTIS has a fairly high electronics spec. And, as with most things, once you've got used to having something, it is hard to imagine being without it. When we started cruising in 1994, we had everything we currently have except for a satellite phone, which gives us the ability to send e-mails from the boat. We have had that facility since 1999 and can hardly remember the time when we could not do so.

We have divided our electronics into three categories and the inventory is as follows:
*indicates items that were installed when the boat was new in 1994 and are still functioning and in use.

SAILING
Autopilot
*Autohelm 7000 Instruments
*B&G Hydra II Echo Sounder
*B&G Radar
*Raytheon R41XX GPS
*Phillips Navigator,
Magellan 315 Weatherfax
*Furuno Fax 207 Laptop (for electronic charts)

As for priorities, we cannot pick three. It has to be four and they are: an autopilot, instruments system (including at least a log and echo sounder), GPS, and radar.

COMMUNICATIONS
SSB Icom IC-M710
VHF Horizon Intrepid
Satellite Phone Iridium
Laptop (for sending e-mails)

The priorities have to be the two radios: SSB and VHF.

Note that none of the communications equipment has lasted the course. It has all been replaced at some stage.

COMPUTERS
PC and two laptops (see above)
Printer
Scanner

All of this type of equipment is extra to basic requirements. It enhances the quality of our cruising, however, and personally we would not like to be without them. In particular we would miss the laptops for sending e-mails at sea and electronic charts. We use the computers for publishing, producing 3 diving guides in the Caribbean, so it is possible to work from a boat.

Our computers survive quite well on the boat except for floppy disk drives (and the disks). CDs and CD writers have made floppies redundant so we no longer suffer from corrupted disk problems.

We also have experimented with a Pocket PC (HP Jornada) which Brian has interfaced with the instrument's network. This sits in a cradle in the deckhouse, and as well as displaying all the sailing and navigation information, provides trend analysis of the data, so we can determine wind shifts, increasing wind speed and so on. It also uses alarms for wind strength, depth, weatherfax receiving times, SSB nets, etc. We have only used this on one ocean trip so far but it has proved really useful in picking up wind shifts (we always used to argue over what the wind was blowing an hour ago).

Brian is still working on the program but if anyone is interested in trying out a copy (it will run on any Pocket PC, but not Palm), then contact us through SetSail.

SAILING ELECTRONICS
Autopilot

Sailing shorthanded makes an autopilot an essential in our view. However, by preference, we use our Monitor windvane--it's much quieter, uses no power and steers a better course under sail. Our autopilot is used for steering under power and in very light winds under sail. We have a back up tiller autopilot that is rigged to drive the Monitor windvane if the main autopilot fails.

With all fingers crossed and clutching a large piece of wood, we are pleased to say that the Autohelm has been 100 percent reliable.

We have a control point at the helm and one in the deckhouse along with a joystick. This enables us to steer the boat from inside the deckhouse. We rarely use the joystick, it is handy sometimes but we wouldn't bother again.

Sailing Instruments

We like to surround ourselves with information so we have lots of instrument displays around the boat (6 digital: 4 in the cockpit, 1 in the deckhouse and 1 on the chart table, plus 4 analogue displays in the cockpit)

The instruments are interfaced to the GPS, so from the helm we can see:

Wind direction and speed
Course over the ground, heading, and bearing to the waypoint
Boat speed and speed over the ground
Distance to waypoint
Depth

Our aim is to have all the sailing and navigation information available whether we are in the cockpit, the deckhouse or at the chart table. This we see as a safety issue as well as enhancing the pleasure of sailing a well trimmed boat, as it is then possible to make navigation and sail trim decisions from the helm.

Generally we have been happy with our B&G instruments except that we have had persistent problems with the displays fogging up. B&G have honored their obligations to date and have replaced the units twice but the problem has recurred and we now keep the displays covered whenever they are in sunlight--not an ideal solution.

Echo Sounder

Of course every boat needs an echo sounder. Ours is a B&G unit that is part of our instrument package. We also have a portable hand held depth sounder which we use from our dinghy to identify good diving sites, which also serves as a back up in the event of our main depth sounder failing (and when we are going stern to a shallow dock).

We have considered fitting forward looking sonar. When cruising in areas of coral reefs or uncharted regions a standard depth sounder is of minimal value. In clear water eyeball navigation works well enough, but in turbid water a forward looking sonar would be useful. (Don't assume that if there is coral the water will be clear. Inner lagoons often have turbid water masking old reef structures.)

Radar

One of the reasons for choosing the Raytheon R41 was that it had a MARPA function--allowing us to track the course and speed of shipping. Although we use this occasionally, it is not the radar's most useful function.

A function that we do use is the sleep mode. At night on passage the radar is set to standby and we choose an appropriate interval--generally 10 or 15 minutes--for the radar to switch to scanning mode and then return to standby.

We also use a guard alarm so that an audio signal indicates any objects within the range that we have set.

The other main use we make of the radar, and arguably its most important function, is when we are approaching land. It is an accurate measure of distance off, which is invaluable when cruising in areas where the charts are unreliable.

If we were fitting out a boat and had budget restrictions, we would make radar a high priority but a basic model would suffice.

A key aspect of the radar is the display location. Ours sits at the front of the deckhouse, where we sit for most of our watches. If the radar cannot be easily used and seen its usefulness drops significantly.

GPS

These days most cruisers would consider a GPS an essential item. Most people also carry a back up. Our main GPS has many functions and is interfaced to both our radar and instruments. Again though if budgetary constraints meant we could carry one hi-spec GPS or two basic models, we'd opt for the latter.

Weatherfax

We found that we could get a better signal using our SSB receiver for weatherfaxes so we simply use the weatherfax as a printer, taking the signal from the SSB radio and printing out the chart on the weatherfax.

You can of course down load the signal to a computer and view the chart on the screen making the weatherfax surplus to requirements. However we like to have a paper chart to look at and argue over, and the weatherfax gives us that option.

Laptop (for electronic charts)

We have an old laptop from when we upgraded to a new model that we use exclusively for our electronic charts. It sits permanently in the deckhouse so we can see it from the inside steering position.

We cruised for five years without electronic charts and for the last two with them. Whereas we would never do without paper charts we do find the electronic charts very convenient. Once they have been corrected for the local area they can be relied upon, but when approaching a new area you need to exercise caution as the errors can be significant. We have been at anchor with the chart showing us half way up a mountain and in Samoa it was a mile out on the entrance to a harbor.

COMMUNICATIONS
SSB

We use our SSB to receive weatherfaxes, to contact shore stations that monitor yacht movements (e.g. Russell Radio in New Zealand), and to speak to our friends.

We do not use it to make telephone calls or for e-mails. We have an Iridium phone for these functions.

The most valuable role for the SSB is probably receiving weather information although we will shortly be testing some of the newer e-mail weather services. Although weather is the most grown up use we make of the radio, the most fun we have with it is talking to our friends. We arrange times and frequencies to chat and it allows us to make arrangements to meet with friends.

VHF, handheld VHF

We recently bought a new VHF which incorporates an external hand set allowing us to talk and receive from the helm (the main set is in the deckhouse). It has proved its worth over the last 6 months of cruising. When entering a harbor the helmsman can talk to the harbor master while the other crew member is working on the deck.

Our handheld VHF is both a back up radio and is also our means of communicating when one of us is ashore.

Iridium

This is a recent acquisition. See our comments in August 2, 2001 log.