australia:handcrank
hand crank torch radios for disasters and hiking
Introduction
the prime role of these devices is to provide a short amount of emergency power for either your smartphone, a torch or radio by using a hand crank which you rotate at around 120-150 rpm to drive a dynamo which can then create a charge - usually enough to power your device for a couple of minutes per minute of cranking
the secondary role of most of these devices is as a power bank which not only can store the hand cranked charge but can also be charged via USB or, in many cases by a small attached solar panel.
these power bank batteries are generally lithium batteries now, mostly 3.7V 18350 batteries up to around 2500mAH capacity which is the maximum safe amount for 18350 sized cells
smaller units may have smaller batteries and many do not allow user to replace them.
these batteries should be charged every 2-3 months and should not be used continuously if you want to prolong their life - they generally have around 500 charge-recharge cycles lifetime
they should not be exposed to very high temperatures
they generally should be above 0degC to charge
most have a USB-out to charge your smartphone and other devices
the other roles these can play and other functions they might have are:
analog AM/FM radio
some have SW as well but this is now of very limited utility and the small antenna and usually limited tuning controls further limit this use
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in Australia, you don't need the NOAA weather radio channels (these are for USA and Canada only)
usually mono speaker but some have a stereo headphone port
LED torch with SOS blinking option
LED reading lamp - some have a proximity sensor to optionally activate the light as you walk past for 30secs
red LED - very few have these, but the Retekess does have a red SOS LED
SOS loud siren
LCD display with alarm clock with sleep
battery meter
MP3 player - either via microSD slot or Bluetooth
aux in port to play music by wire from your smartphone, etc
weatherproofing
ultrasonic dog whistle - not many have this!
should be small enough and light enough that you will actually take it with you
should have a sturdy, reliable hand crank
should have some weatherproofing eg. IPX3 as minimum - you are likely to need this in bad weather!
the lithium battery should be user replaceable unless you plan on buying a new one every 2 yrs or so
must have USB in to charge
must have USB out to power your smartphone, etc
LED torch with SOS blink - assume your smartphone dies or falls off a cliff
AM/FM radio
optional:
headphone socket is a very nice addition - gives stereo audio instead of just the mono speaker output
solar panel - these are not essential but could be useful if there are many days without access to power but they are not going to be great giving less than 1W charge per hour
red LED is nice at night to avoid upsetting your night vision
MP3 player - not sure if this is very useful
reading lamp
SOS siren - might be handle if you forget your whistle
Bluetooth - not really a good idea as it uses up lots of hand cranks of power
AAA batteries use as an option instead of the rechargeable battery
Models available in Australia in 2021
australia/handcrank.txt · Last modified: 2021/07/26 20:31 by gary1