Caravans

Including Sheds, Motorhomes, Vans and anything else on land with a flat roof.

Fitting a phone usually involves the provision of an external powers supply and an external antenna. If full hands free operation of the phone is required  a car kit can be fitted .

Antenna

Caravans with aluminium roofs make ideal antenna sites because of their height above the ground and the good flat earth plane.  Normally a bodymount such as the Base 2000 is the preferred option in that it is simple to fit (single hole fixing) and the antenna element can be unscrewed without tools so can easily be removed for cleaning of the caravan or during travelling if desired.  Aluminium is easily deformed so if manoevering under trees or other overhanging obstacles it is a good idea to remove the antenna element.  If you mount the antenna near a roof hatch this makes removal of the radiator element easier.

If the vehicle roof is not metal (eg fibreglass) then the same strategy can be used but a sheet of alumium approximately 12" square (or sticky aluminium foil can be used) must be affixed to the inside surface of the caravan and the mounting hole drilled in its centre.  Mounting on the outside isn't recommended both from the aesthetics of the fixture and the difficulty of achieving good earth braid/plate contact (the earthing prongs are on the lower part of the antenna installation).

The antenna should be mounted about 12" in from the edge of the caravan to allow easy access and also sufficient earth plane.  It is oftn convenient to mount it over a built in cupboard or wardrobe to allow the cable to be brought down inside the caravan out of view.

base 200 earthing contacts

If for any reason  a roof mount isn't acceptable then a temporary solution is to use a sleeve dipole such as the window clip mount however these are now only available for 900MHz (Vodafone/Cellnet).

Windoe Clip Antenna

This can be placed over a sliding window or mounted externally on a suitable pole.  The cable connector will need protection against the elements if mounted outside (see self amalgamating tape)

Power

Power is usually going to come from batteries within the caravan or from the host vehicle.  Although most phone chargers take a fairly small drain compared with lights and other electrical fittings in a caravan the normal precautions against the vehicle battery becoming discharged should be in place.  These usually involve some form of relay so that the car battery is disconnected from the caravan services once the engine stops. 

Don't forget that the 12 or 24VDC supply within a caravan is usually coming from a battery with a very low internal resistance.  Any cabling fault will lead very high currents flowing and unless suitable protection devices are in place (fuses or circuit breakers) the wiring loom will reach a temperature at which its insulation will ignite in only a few seconds.  It is especially important to ensure circuits are suitably protected when adding to them.  An electric fridge might be protected by a 30Amp fuse and it would be wrong to simply take a phone charger circuit on 5A cable from that without an extra fuse near the source to protect the wiring.

The simplest form of charging involves using a modified car charger.  Mounted in a surface mount box this gives a neat permanent fixing for the charger lead and if combined with a simple holder is usually a very satisfactory solution.

In the example shown on the right the charger circuitry is contained in a box with a charge indicator light, a switch can also be fitted on the box but in this case the supply was externally switched.  The power supply wires (12 to 28VDC) are brought in at the rear of the box which was mounted on the side of a cupboard.

 

The phone was usually hung on a simple bracket (shown below)

12-28VDC bulkhead mounting charger and phone clip.

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