Frequently Asked Questions

The information provided on this page provides a general guide to questions and answers that come up from time to time. Please check the details of the unit you are wishing to buy on the merchants website prior to buying to ensure that the unit is suitable for your needs and offers all the facilities and options you need.

1. What is satellite navigation?
2. Is it safe?
3. What are Points of Interest?
4. Do I need a licence to own one - do I have to pay a licence fee?
5. What is a Route?
6. What is a Waypoint?
7. Do I need an external aerial?
8. Can the maps be upgraded?
9. Just how precise are they?
10. Can satnav systems take account of traffic delays and roadworks?

1. What is satellite navigation?

A number of satellites were placed in orbit around the planet by the US government. These were originally intended to help the US armed forces to navigate in the battlfield. Today, however, anyone can use these satellites to navigate. The satellite navigation system receives the transmissions from the various satellites, and, using it's software, can calculate its current position on the earth. This position is then used to show your current location on the streetmap built into the unit and to calculate the route to your destination.

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2. Is it safe?

Some people have asked whether there is a radiation concern from using these devices in an enclosed space (such as a car) in the same way as some people are concerned with radiation emitted by mobile phones.

The satnav unit is only RECEIVING satellite information and NOT transmitting so in this respect it is safe.

The other aspect of safety that drivers SHOULD be concerned about is operating the unit whilst in the vehicle. Under no circumstances is it wise to operate the unit whilst driving. Taking your concentration off the road in order to use the system could result in a car crash or knocking down a pedestrian - either of which could be fatal. Whenever you wish to use your satnav system please pull over.

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3. What are Points of Interest?

Many systems today come with Points of Interest (POI) databases. These include the locations of petrol stations, hotels, hospitals, cinemas etc.

The user can normally tell the system to navigate ot the nearest point of interest - nearest petrol station, nearest hotel etc..

Many systems allow you to add your own Points of Interest as well as favourites. Setting your "home" and "office" destination can help you to navigate quickly to a favourite destination.

Some systems also allow you to download POI databases - safety/speed camera databases are very popular.

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4. Do I need a licence to own one - do I have to pay a licence fee?

The satellite transmissions are paid for by the US government - there is no charge to the end user and no annual "licence" is required. The European Union and the European Space Agency have teamed together to launch the Galileo satellite system.

The first of 27 satellites was launched in December 2005 with the plan to have all 27 satellites launched and operational by 2010.

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5. What is a Route?

A Route is the series of roads that your car must take in order to get from location A to location B. The satnav software calculates the optimum route for your journey based on the information you give it - current destination, final destination, any roads to avoid and how to calculate the route.

You can normally calculate routes in a variety of ways - shortest route (in terms of distance), quickest route (in terms of time), avoiding toll roads/motorways and avoiding specific roads.

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6. What is a Waypoint?

A Waypoint is any location you wish to visit on a journey to your chosen destination. For example, you may wish to visit a cashpoint or petrol station before going to a hotel - the cashpoint is a "waypoint" and the hotel is the "destination". You can tell the unit to visit the cashpoint before going to the hotel.

On the Garmin 2610 and 2620 machines you can enter multiple waypoints and the software will calculate in which order to visit the waypoints in order to optimise the journey! As you would expect, these systems are not cheap - but they are a real investment for sales professionals and delivery drivers/couriers.

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7. Do I need an external aerial?

Some vehicles have athermic heat-reflecting windscreens or built-in windscreen heating devices. In this instance, you may find that the satellite receiver built into the system cannot receive the satellite signal.

In this instance you would be wise to buy an external patch antenna.

You will often find that on such vehicles there is a small area of glass close to the bottom of the windsreen that is not covered by the heat-reflective coating - this would be the ideal position to place your external aerial.

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8. Can the maps be upgraded?

From time to time manufacturers will release upgrades to not just their maps, but also the software that runs the system - adding new features and fixing problems in extising software.

These can either be downloaded from the manufacturers website or ordered on CD. Some minor upgrades are free of charge - such as fixes for bugs in the current software release. Other larger upgrades require a fee to be paid.

Each system is different so it is worth checking out the requirement with the manufacturer prior to purchase.

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9. Just how precise are they?

The number of satellites your receiver can see can be affected by the weather, the locality (ie. high buildings and trees) and where the receiver is placed in the vehicle.

The more satellites that your receiver can see, the more accurate the position it can give you.

The GPS satellites, for civilian use, can provide an accuracy of less than 25 metres - indeed in reality it is a lot less than this - usually down to 3-5 metres for the majority of the time.

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10. Can satnav systems take account of traffic delays and roadworks?

Some systems come with Traffic Management (TMC) systems built-in. These receive traffic information in a similar fashion to the way a car radio would. This information can then be used by the satnav system to navigate the driver around the congested area.

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We will expand this FAQ's page over time - if you would like us to add specific FAQ's please email us - webmaster (at) satnavsource.co.uk - thank you.