VHFs a quick guide
VHF radios work on line of sight communication. Roughly a fixed VHF set will work over 10-40 miles depending on the height of the antenna, a portable VHF has less power and with the antenna on the set you can expect between roughly 3-12 miles range.All operators do require a licience to use them.We do not need to see the licience for you to purchase, we do reccomend you do the test and obey the regulations with regard to the use of the emergency proceedures and channels.There is imformation available on the website radio.gov.uk
Fixed VHF radios are mostly 25 watts in power and run on a 12 volts battery. They can be disconnected and taken home for security.They need to be fitted with a VHF antenna which should be mounted as high as possible.Most options we sell are water resistant and splash proof and some are waterproof on the front when flush mountedHand held VHF are portable with their own antenna fitted and have their own power from a detachable battery pack. Therefore completly self contained if your boat power went down or you had to get in a dinghy or liferaft in an emergency.
The batterys can usually be charged on your mains at home and trickle charged from your 12volt boat supply. You can get spare battery packs to enable you to swap over and have a radio consistantly in operation. We supply all h/h VHF with a charger, please refer to the specification.
It is advisable to use a waterproof bag for most sets.You can get a little bit better range by connecting the set to a fixed antenna mounted as high as possible.Currently fixed VHF sets are still being sold and used by majority of people for approximatley the next five years. You can buy a DSC VHF or an upgrade for your current VHF to fit DSC, only with compatible sets. This has the ability to send a signal to the rescue services with you position and boats detail.
Hand held VHF are still being sold and used. Some DSC compatible hand held radios are now coming on the market. DSCAs regulations stand no one is under any legal obligation to fit or change to DSC equipment unless they are a classed vessel with a specific maritime organisation governing the standards and levels of equipment to operate eg ships over 300GT (IMO regulated). In the UK the coast-guard will no longer be obliged to maintain a normal CH16 watch except to facilitate emergency functions after 2005. So making a routine call on voice will have to be established using DSC. It would be wrong of me to say that someone in distress with regular VHF using Channel 16 will not be heard. But out of range of UK communications DSC is your only guarantee of help from a station within range. IMO regulations have relieved classed ocean going vessels of their responsibility to monitor Channel 16 at all. This is current and not planned. Therefore someone in the middle of the English channel in a yacht in trouble has no guarantee of help from a ship. However a DSC alert on VHF triggers alarms etc on the bridge of the ship and a response is compulsory under maritime regulations. A ship cannot also claim the distress was not received because their equipment records it electronically. Also some European coastal agencies are not responding to 16 anymore so DSC from a foreign cruising point of view is almost essential.
Sounders a quick guide
Most of the sounder options will be powered by a 12volt battery [ie the boats supply] except the portable versions which are supplied with a portable battery pack[batteries not included]
Most of the sounders we sell will be sold with a transom mounted transducer which can also be glued in hull and the signal will shoot through a single skin of fibreglass.
The portable sets have a suction mount transducer for tempory fitting. Most of the sets will have the option of being able to fit different transducers except the economy models .Most of these sets are used on small powercraft with outboards and sterndrives.
The forward looking sounders come complete with an through hull transducer which envolves making a hole in the hull.
If you have a woodern boat/concrete boat/steel boat/double skin grp boat/sailing boats or a boat powered by a inboard motor with propellor drives under the boat[ie not a outboard or sterndrive] you will need to fit the transducer thru the hull, ie drilling a hole in the hull.
The transducer gets a signal by bouncing an echo off the bottom of the sea of river bed and measures the distance when the echo returns.You can buy a in-hull [shoot thru a single skin of grp] transducer if you can not get a good signal with the transom version. The instuctions supplied with the sets give you good hints and tips to fitting the sets and transducers.
Transducer Location - General
1. Thetransducer must be placed in a location that has a smoothflow of water at all times. If the transducer is to be mounted inside the hull, then the chosen location must be in the water at all times. If the transducer is not placed in a smooth flow of water, interference will show on the sonars
display in the form of random lines or dots whenever the boat is moving.
2. The transducer should be installed with its face pointing straight down, if possible.
3. If the transducer is mounted on the transom, make certain it does not interfere with the trailer or hauling of the boat. Also, don not mount it closer than approximately one foot from the engines lower unit. This will prevent cavitation interference with the propeller. Typically, the transducer should be mounted as deep in the water as possible. This increases the chance that it will be in the water in high speed and reduces the possiblity of air bubble interference.4. lf possible, route the transducer cable away from other wiring on the boat. Electrical noise from engine wiring, bilge pumps, and areators can be displayed on the sonars screen. Use caution when routing the transducer cable around these wires.
The sets with the greyline have the ability to determine the different bottom materials ie rock mud etc.
The more expensive the sets usually have better definition and screen quality measured by pixels on the screen.
The more power output the set has means the sets receive a stronger signal and work at lower depths better.
Speed Temp Options
Some of the options have a speed /temp option. These come complete with a transom mounted paddle wheel assembly.This displays speed and depth on screen as a all in one set. Some are sold as a complete package.General electronics a quick guideMost of the general electronic range is powered by a 12volt supply and is made for the marine enviroment. Check whether the set is to be mounted inside or outside the boat[ie water resitant to splashes or waterproof for immersion]