I’ve been testing this universal external battery from Amstron for the last month or two. When I venture into New York City for the day I’m often away from any source of electrical power. There’s nothing worse than having your device power down on you 1/3 of the way through the day.
The Amstron P33 supplies power via a USB port. This is a great method because it means in a pinch I can use most of the charging cables for my devices (the manufacturer notes that the iPhone 3G cannot be charged via its own USB cable – you must use the included retractable cable and tip). In many instances there’s no need to buy additional tips unless you don’t have a USB cable. There is a handy retractable cable included. Pair this up with any of the 6 charging tips to create a charging cable. Additional tips are sold on the manufacturer’s web site.
There are 6 tips included with the battery. I tested on my BlackBerry Bold and iPhone 3G and iPhone Touch (2G). All tips worked perfectly when connected via the included retractable cable.
Here’s a list of the devices the manufacturer say’s the battery is compatible with:
To re-charge the Amstron P33 you simply use the mini-USB port and retractable cable. There is an included power plug that accepts a USB connector. Plug this into the wall and re-charge. The manufacturer indicates the re-charge time will be 6 hours. In practice I always re-charged overnight.
There are 5 LED lights that indicate the remaining charge on the battery. In practice I found the device would fully recharge my iPhone in about an hour and still have about 1/2 the power remaining as measured by the LED lights. More typically I would use the battery as supplemental power to my devices and plug them in when their battery indicators approached zero.
Here are the specs as stated by the manufacturer:
4X Battery Life for iPhone
Increase the life of your Apple iPhone by 4 times with the Amstron PP33 battery and charging system.
# Chemistry: Li-Ion
# Capacity: 3400mAh
# Output Voltage: DC 5.5V
# Output Capacity: 700mA
# Charging Mode: USB or USB AC adapter
# Charge Time: 6 hours
# 5 Level LED Display
# Use with your iPod Video for an extra 2.5-3 hours of play time
# Includes: Samsung, Mini USB, Treo, LG, iPod, PSP connectors
# Warranty: 1 Year
Package Includes: miniUSB tip, Samsung tip, iPod tip, LG tip, Palm Treo Tip, Sony PSP tip, Retractable USB Cable, AC Jack, & PP33
Note: For Apple iPhone 3G you must use retractable cable that comes with PP33. Will not work with Apple’s USB Cable
Link: Amstron P33 -$40 via ATBatt
What I Liked:
– Powers multiple devices
– Retractable charging cable included
– USB connector accepts most (not iPhone 3G) OEM charging cables
– Easy to put in my pocket or backpack for quick trips
What Could Be Improved:
– Include more tips
– Increase the size and add even more battery power
– Fold out charging (AC) prongs so you don’t need to carry a charging block
I'd also list it as a negative that this device is really weak in the amperage department. For example, it can't power my HP 310 unit (Windows CE navigation unit) because it requires more than the 700mA available even though it uses a normal mini USB connector. I know this can really confuse people when they don't know to look at the amperage, not just the voltage – something like this would plug in and light the charge light (dimly), but never send enough juice to actually charge the unit. It took me a while to figure out why a 3rd party USB-based charger wasn't working! Now I've learned to look at both figures.
Many multi-adapters today offer amperage up to 2A to really service as many device types out there as possible. This really would be of much wider benefit if it would do that as well.