Choose a GPS Receiver for Recreational Purposes

How to Choose a GPS Receiver for Recreational Purposes(3)

Steps

6.While there are countless GPS brands on the market, Brickhouse Security provides excellent GPS tracking devices:

Brickhouse Security: http://www.brickhousesecurity.com/gps-car-tracking-vehicle-logging.html

Lightning GPS: http://www.lightninggps.com/

7.Visit the following stores in your local area to see if they carry the model you're looking for:

Outdoor/trail shop - Anywhere that sells hiking or camping equipment

Hardware store - Many hardware store chains sell GPS units in their hunting/outdoor departments.

Department store - Stores such as WalMart carry GPS units in their hunting/outdoor departments.

Marine equipment store - Even handheld units can be often be found at boat equipment shops.

8.The most important thing to remember about any handheld GPS unit is that the tiniest detail can ruin the experience for you. Buttons that are too small, or located in awkward places, or units that are *just* too big to fit in a certain carrier, etc. can all be deal breakers. The best way to deal with these challenges is to be sure that there is a money-back guarantee or return policy if you find that the unit doesn't work for you in a practical environment. To this end, be sure to set aside time as soon as possible to test your new unit out as much as you can before your return policy runs out.

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Choose a GPS Receiver for Recreational Purposes

How to Choose a GPS Receiver for Recreational Purposes (2)

Steps

4.If you prefer a vehicle/boat mount unit, examine sizes, possible mount locations, antenna configurations etc. that are right for you. Consult your retailer for options. Some marine GPSs come with built-in fish finder features as well.

5.If you prefer a handheld unit, consider the following additional features and how important they are to you:

Colour screen - More expensive, but some people find them easier to read

Battery requirement & consumption rate - how many batteries does it take, which type, and how long does it take to drain them? Would you prefer a rechargeable unit?

Electronic compass - telling what direction you are facing while you are standing still. GPS units without this can only report your direction when you are moving.

Barometric altimeter - calculating altitude based on air pressure

Mapping - Displaying your current position on a map, uploading extra/custom maps into your unit

Data entry - Some GPS units only allow you to upload waypoints from a PC, while others allow you to enter them while in the field

Communications - Some GPS receivers have built-in two-way radios (ie: walkie talkies) to allow for communications as well as navigation. These units may provide position-sending functions so that you can locate others in your party

Removable memory cards for maps - Some people prefer to be able to swap maps while in the field, rather than connecting their GPS unit to a laptop. You may purchase a GPS that provides a CompactFlash (CF) or SecureDigital (SD) slot for map cards if this is important to you.

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prolong lithium-ion battery's life

prolong lithium-ion battery's life (四)

Longevity of high-power lithium-ionGenerally speaking, batteries live longer if treated in a

gentle manner. High charge voltages, excessive charge rate and extreme load conditions will

have a negative effect and shorten the battery life. This also applies to high current rate lithium-

ion batteries. Not only is it better to charge lithium-ion battery at a slower charge rate, high

discharge rates also contribute the extra wear and tear. Figure 3 shows the cycle life as a

function of charge and discharge rates. Observe the good laboratory performance if the battery

is charged and discharged at 1C. (A 0.5C charge and discharge would further improve this rating.)
Figure 3: Longevity of lithium-ion as a function of charge and discharge rates. A moderate

charge and discharge puts less stress on the battery, resulting in a longer cycle life.Battery

experts agree that the life of lithium-ion depends on other factors than charge and discharge

rates. Even though incremental improvements can be achieved with careful use of the battery,

our environment and the services required are not always conducive to achieve optimal battery

life. The longevity of a battery is often a direct result of the environmental stresses applied.

prolong lithium-ion battery's life

prolong lithium-ion battery's life (三)

The voltage level to which the cells are charged also plays an important role to longevity. For

safety reasons, most lithium-ion cannot exceed 4.20 volts per cell. While a higher voltage boosts

capacity, the disadvantage is lower cycle life. Figure 2 shows the cycle life as a function of charge

voltage.

(Figure 2: Effects on cycle life at different float charge levels (Choi et al., 2002)Higher charge

voltages boost capacity but lower cycle life.)

There are no remedies to restore lithium-ion once

worn out. A momentary improvement in performance is noticeable when heating up the battery.

This lowers the internal resistance momentarily but the condition reverts back to its former

state when the temperature drops. Cold temperature will increase the internal resistance.If

possible, store the battery in a cool place at about a 40% state-of-charge. Some reserve charge is

needed to keep the battery and its protection circuit operational during prolonged storage. Avoid

keeping the battery at full charge and high temperature. This is the case when placing a cell

phone or spare battery in a hot car. Running a laptop computer on the mains has a similar

temperature problem. While the battery is kept fully charged, the inside temperature during

operation rises to 45°C (113°F). Removing the battery from the laptop when running on fixed

power protects the battery from heat. With the concern of the battery overheating and causing

fire, a spokesperson for the U.S. Consumer Product Safety Commission advises to eject the

battery of affected laptops and to run the machines on a power cord. It should be noted that on a

power outage, unsaved works will be lost.The question is often asked, should the laptop be

disconnected from the main when not in use? Under normal circumstances, it should not matter

with lithium-ion. Once the battery is fully charged, no further charge is applied. However, there

is always the concern is malfunction of the AC adapter, the laptop or the battery.A large number

of lithium-ion batteries for cell phones are being discarded under the warranty return policy.

Some failed batteries are sent to service centers or the manufacturer, where they are

refurbished. Studies show that 80%-90% of the returned batteries can be repaired and returned

to service.Some lithium-ion batteries fail due to excessive low discharge. If discharged below 2.5

volts per cell, the internal safety circuit opens and the battery appears dead. A charge with the

original charger is no longer possible. Some battery analyzers (Cadex) feature a boost function

that reactivates the protection circuit of a failed battery and enables a recharge. However, if the

cell voltage has fallen below 1.5V/cell and has remained in that state for a few months, a

recharge should be avoided because of safety concerns. To prevent failure, never store the

battery fully discharged. Apply some charge before storage, and then charge fully before use.All

personal computers (and some other electronic devices) contain a battery for memory back up.

This battery is commonly a small non-rechargeable lithium cell, which provides a small current

when the device is turned off. The PC uses the battery to retain certain information when the

power is off. These are the BIOS settings, current date and time, as well as resource assignment

for Plug and Play systems. Storage does shorten the service life of the backup battery to a few

years. Some say 1-2 years. By keeping the computer connected to the main, albeit turned off, a

battery on the PC motherboards should be good for 5-7 years. A PC should give the advanced

warning when battery gets low. A dead back-up battery will wipe out the volatile memory and

erase certain settings. After battery is replaced, the PC should again be operational.