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PC TREASURES Battery Station / 08767 /
PC TREASURES Battery Station / 08767 /
Offered by FastMarketPro
Price: $29.52
3 used & new from $29.52

5.0 out of 5 stars This universal charging station is a keeper! (Just don't get too excited about recharging alkaline cells), April 17, 2014
[Note: My review was originally written back in August 2013, for the White version of this charger. Amazon later separated different color versions into different product pages, and the white version is currently unavailable.]

I already have two 'universal' chargers that can handle AA/AAA/C/D and 9V batteries: the original Rayovac PS3 and the Tenergy TN190. This product (PC Treasures ChargeIt! Battery Station) attracted my attention since it seems to combine advantages of both PS3 and TN190, plus additional features.

The ChargeIt! Station Pro is a 'Smart' charger that monitors each cell independently, just like PS3 and TN190.
- It is able to recharge alkaline cells (like the PS3) in additional to NiMH and NiCd types
- It has an LCD display panel (like the TN190) that shows individual battery status
- It can recharge high-capacity C & D cell (the PS3 can only handle up to ~3000mAh)
- It has two USB ports with output capabilities of 1A and 2A, respectively (the TN190 only has one 500mA port)
- It accepts 12V input, which means it can be powered from car battery with a simple CLA (cigarette lighter adapter)

The ChargeIt! Station Pro claims to offer "microprocessor monitored charging". This seems to be true based on my observation.
- When a battery of unknown status is inserted, the charger first sends severel current pulses through the battery, presumably to determine the battery status and chemistry.
- For a NiMH cell, the charger starts with ~800-850mA. As the battery gets closer to being fully charged, the charger switches to lower duty cycle to reduce the average current. It stops (LED changes from Red to Green) when a negative voltage slope is detected.
- For a NiCd cell, the charger starts by discharging the cell (LED=Yellow), then follows by a recharge (LED=Red) similar to the case for NiMH.
- For an alkaline cell, the charging current starts at ~80-100mA. As the battery voltage gets higher, the charger switches to lower duty cycle. It stops when battery voltage is high enough (over 1.55V approximately)
- The charger is intelligent enough to detect error conditions such as: wrong battery type selected, reverse polarity, completely exhausted cell (under 0.1V). The Red LED blinks in case of fault.

After playing with this charger for a week, I found it to meet my expection in every aspect. I have used it to recharge different batteries, including C-size NiMH (Tenergy Centura C), AA LSD NiMH (Sanyo eneloop), and ordinary alkaline AA cells (Duracell Copper Top) without problems. The two USB ports also come in handy for recharging my tablets. Unlike the case for TN190, the USB ports of ChargeIt! Station do not turn off when batteries are inserted into the charger.

The only minor concerns I have are:
- The LCD panel needs a backlight
- The charging current of 850mA is too low for high capacity D cells. It will take over 12 hours to fully recharge a 10,000mAh cell.
- The 9V charging port seems to be dumb. It simply charges at 40mA for about 8 hours.

The capability of recharging ordinary alkaline cells is useful when I'm in a pinch. On the other hand, it is important for one to have a realistic expectation. Based on my experience:
- You can never recharge an alkaline cell back to its original capacity. You may get 70% the first time, less with every subsequent charge.
- You can only recharge an alkaline cell a handful of times before its capacity drops too low, or it starts leaking.
- You should use freshly recharged alkaline cells immediately. Don't let them sit on the shelf or inside unused appliances. They may leak if the gas pressure inside is not released soon.
- Do not recharge 9V alkaline battery with this charger. It will either rupture or leak.

Conclusion:
At its present low price (similar to that of the TN190), I consider this ChargeIt! station to be a better value just for the two USB ports. Consider the added capability of recharging alkaline cells as a bonus, but don't weigh it too much in your purchase decision.


USB Mini Charger Doctor Current Test Tool Voltage Test Tool Amp Volt Reader
USB Mini Charger Doctor Current Test Tool Voltage Test Tool Amp Volt Reader
Offered by BESTOPE
Price: $6.09
8 used & new from $3.68

2 of 2 people found the following review helpful
2.0 out of 5 stars Does not cycle between Voltage and Current when loaded, April 14, 2014
I have over one dozen USB-powered devices (tablets, cell phones, power banks, etc.) in the house, plus almost equal number of USB power adapters. Sharing USB power supplies among different USB devices is a process of trial and error, since most manufacturers don't provide accuracte description for input/ouput power specs. That's why this USB Mini Charger Doctor sounds like an useful tool for me.

The USB Doctor is supposed to display the USB port's output voltage and load currently alternately, so that I can monitor its charging progress and also calculate the output power (voltage * current). In actual testing, however, it does not work as expected.

With no load connected to the USB Doctor, the red LED display correctly cycles between voltage and current reading every 5 seconds or so. But when there is a load connected, the display stays stuck in one mode (either voltage or current) and does not toggle. The only way I can see the other mode is to disconnect the load, wait for the display to switch mode, and then reconnect the load again.

I can't tell if my unit is defective or its behavior is by design, since the unit came with ZERO instructions. In any case, the unit is going back for a refund.

Aside:
I verified the accuracy of voltage and current readings using a Digital Multimeter. The readings are consistent to within 5%, which is acceptable.
Comment Comments (4) | Permalink | Most recent comment: Apr 17, 2014 8:38 AM PDT


iGo International 4-Position Charger with Four "AA" Batteries
iGo International 4-Position Charger with Four "AA" Batteries
Offered by Action Gear
Price: $9.99
3 used & new from $9.99

4.0 out of 5 stars Charger is SMART but slow. Batteries have limited capacity and lifespan, April 10, 2014
This product (iGo International 4-Position Charger with Four "AA" Batteries) contains an 'iGo green' 4-slot AA/AAA charger, plus four 'iGo' rechargeable alkaline AA batteries.

There are several aspects I like about the iGo charger:
1. It is capable of charging both NiMH and RAM (rechargeable alkaline manganese) batteries. Most chargers are designed for NiMH only and cannot handle RAM batteries.
2. It is 'smart' in that it monitors the voltage of battery in each slot, and stops charging when the battery voltage is high enough (approximately 1.4V for NiMH, 1.6V for RAM)
3. It has individual indicator light for each slot. The green light blinks while charging, and stays on when done.
4. It has a slim one-piece design with a folding AC plug
5. It work from universal voltage of 100-240V AC, and comes with plug adapters for Europe and UK outlets

The only problem with this charger is that it is very slow. The user manual says charging current is 200mA for NiMH, 150mA for alkaline. But the actual charging current I measured drops as battery voltage gets higher, to around 170mA for NiMH, 130mA for alkaline. That means:
- To recharge NiMH cells with 2000mAh capacity (such as the Sanyo eneloop AA), it will take about 12 hours.
- To recharge alkaline cells with 2000mAh capacity (such as the IGO AC05058-0001), it will take about 15 hours

Provided that you always keep a spare set of batteries as standby, the long charge time is not a real problem. But if you have a large collection of rechargeable batteries and often need to recharge in a hurry, then definitely look for a charger that can recharge in 2-5 hours. By the way, avoid chargers that advertise less than one hour charge time, since they are bad for battery lifespan. Between 2 and 5 hours, the impact in lifespan is negligible.

The iGo rechargeable alkaline batteries have the same chemistry as single-use alklaine batteries. So it has the same voltage of 1.5V (instead of just 1.25V for NiMH type). They are advertised to have a capacity of '2000mAh', but that is ony possible when delivering a very low current of around 25mA at room temperature. At high current or at lower temperature, the capacity drops significantly. This is because iGo cells inherited the same limitations as alkaline cells: high internal resistance, and poor low-temperature performance.

I measured capacities of iGo cells using my La Crosse BC1000 (at 100mA down to 0.9V), and only observed an average of 1628mAh during the first discharge. Worst yet, the capacity drops quickly with each recharge/discharge cycle:
- After just one recharge (using the iGo charger), the average capacity dropped by 19% to just 1316mAh
- After two more recharge/discharge cycles, the average capacity dropped further by 4%, to 1255mAh

Based on the above trend, I estimate the average capacity of iGo cells will fall below 814mAh (50% of initial value) after another 15 discharge/recharge cycles. That means a lifespan of around 20 cycles. In contrast, Sanyo claims 2nd-gen eneloop cell can last for 1500 deep discharge/recharge cycles, before its capacity drops below 50%. I have many first-gen eneloop cells bought 7 years ago, and they are still working just fine.

All things considered, this package is a good deal just for the iGo smart charger. The four iGo rechargeable alkaline batteries can still be useful in low-drain appliances, such as wireless mouse and keyboard.


BTY 1.2V 1350mAh AAA Ni-MH Rechargeable Batteries-Green+White
BTY 1.2V 1350mAh AAA Ni-MH Rechargeable Batteries-Green+White

1 of 1 people found the following review helpful
1.0 out of 5 stars You want 1350mAh? Connect FIVE of them in parallel!, April 7, 2014
The Amazon description of this product (BTY 1.2V 1350mAh AAA Ni-MH Rechargeable Batteries) claims capacity of '1350mAh', which sounds amazing for rechargeable AAA cells. Suspiciously, on each battery it only says "BTY AAA1350 series" with no mention of its capacity. The actual measured capacity, using my La Crosse BC1000 battery charger/analyzer, is only one-fifth that number.

- Right out of the package, the average remaining charge is only 203mAh. The spread is very large (min=129, max=245), which indicates poor quality control
- After the first recharge/discharge cycle, the average capacity improved slightly to 263mAh
- After another 4-5 cycles, the capacity number reached its peak at 277mAh (min=237, max=305). This is just 20% of the advertised capacity of '1350mAh'

To make sure that the problem is not due to the BC1000 charger, I used another very slow charger (iGoGreen Charger) to top off those BTY batteries AFTER they were fully charged by the BC1000. I then re-ran the measurement, using the lowest discharge current of 100mA. Even after all those extra effort, the average capacity only improved marginally to 288mAh, still just 21% of the advertised value.

In comparison, all the eneloop cells (Sanyo eneloop AAA Pre-Charged) I tested typically exhibit capacity around 830mAh, higher than the advertised '800mAh'.

Conclusion:
Those BTY batteries are advertises as '1350mAh', yet they can only deliver about 20% of that number. I am sick and tired of companies selling junk batteries under completely bogus capacity numbers. They probably thought that most average users cannot tell the real capacity of those junk batteries anyway. Well, now that you have read this review, you should know better.

In case you're looking for inexpensive rechargeable batteries with honest capacity ratings, consider the following low-self-discharge NiMH batteries:
- Tenergy Centura AAA : rated 800mAh, tested ~900mAh
- GP ReCyko Rechargeable AAA : rated 820mAh, tested ~880mAh
Comment Comments (2) | Permalink | Most recent comment: Apr 10, 2014 8:40 AM PDT


Rayovac Backup USB Power Pack with 8AA Battery
Rayovac Backup USB Power Pack with 8AA Battery
Offered by Green Mountain Laser
Price: $14.95
9 used & new from $6.99

3.0 out of 5 stars Primitive voltage regulator / Poor utilization of disposable batteries, April 4, 2014
I purchased this product (Rayovac Backup USB Power Pack with 8AA Battery) from my local HarDware store, because the price was too good to pass (it was cheaper than buying 8 alkaline batteries alone). I figured that it could come in handy in case my neighborhood suffers yet another extended power outage. After testing the PS73 power pack, however, I was disappointed.

I expect the PS73 to contain a power converter to regulate the 5V output at USB port, whether the input battery voltage is 6V (when using a fresh set of 4 alkaline cells) or 4.8V (when using 4 NiMH cells). As it turns out, the PS73 has a simple linear regulator inside, so it is only able to step-down the battery voltage, but not boost up.

When using a set of fresh alkaline cells, the combined voltage is 6V (1.5V * 4), so the USB output port can be regulated at 5V (the extra 1V is wasted internally). As the alkaline batteries become partially used up and the combined voltage drops to 4.8V (1.2V *4), the USB output voltage drops to just 4.5 - 4.6V (the regulator itself drops additional 0.2-0.3V). This is the same situation when using a set NiMH cells (1.2V * 4). An output of 4.5V is borderline too low for most USB-power devices.

How much energy can the PS73 extract from a set of 4 alkaline AA cells?
A typical AA alkaline cell can only deliver 500mA for around 2 hours, before its terminal voltage drops below 1.2V. So the total energy that can be delivered by this charger is 5V * 0.5A * 2 hr = 5Wh. This is a relatively small amount of energy given the size and weight of this package. Just as an example, to fully recharge the 2100mAh lithium-ion battery in my Samsung Galaxy S3 cell phone requires 3.7V * 2.1Ah = 7.8Wh of energy, not counting conversion losses. So the PS73 is only able to recharge my S3 by about 60%, after exhausting one set of alkaline cells.

The 3-LED battery status indicator comes on whenever an USB plug is inserted (there is a mechanical switch inside the USB port to turn on the voltage regulator). It consumes 20mA and is excessively bright. This is just a waste of power - unless you like to use it as a nightlight. The number of LEDs seems to correspond to the output voltage as shown below:
- 3 green LEDs = Over 4.7V
- 2 green LEDs = 4.6 to 4.7V
- 1 green LED = 4.4 to 4.6V
- 1 Red LED = Under 4.4V

Conclusion:
All things considered, the PS73 is still useful as a last-resort charger. Suppose there is an extended power outage and I have exhausted all my rechargeable power bank units, I can put alkaline batteries in this product, just to get some power for my essential USB devices. I consider it an 'Okay' value at the low price I paid. But I cannot recommend it at the present Amazon price (20 USD). For about the same price, you can easily get a power bank unit such as the EC Tech 5600mAh External Battery. It can deliver 3x the energy (15Wh), at half the size and weight of this PS73.

If you need a well-designed power converter that takes alkaline or NiMH cells as power source, consider the Duracell Mobile Charger CEF23AU. It can step down as well as boost up battery voltage, to maintain a regulated 5V output. The converter will continue to function even when battery voltage has dropped to 3.6V, so it is able to squeeze at least 50% more power from a set of alkaline cells.

On the positive side, the PS73 is a lot better than the Burro Mobile Charger. The Burro does not even have a voltage regulator, just a diode and a series resistor inside. Now THAT is a real piece of trash.


TrickleStar 180SS-US-7CX 2160 Joules, Coax Secondary Protection and 4-Feet cord Advanced Energy Saving 7 Outlet PowerStrip Surge Protector
TrickleStar 180SS-US-7CX 2160 Joules, Coax Secondary Protection and 4-Feet cord Advanced Energy Saving 7 Outlet PowerStrip Surge Protector
Price: $39.03
10 used & new from $29.98

1 of 1 people found the following review helpful
4.0 out of 5 stars Good energy-saving power strip with adjustable trip threshold, March 31, 2014
This product (TrickleStar 180SS-US-7CX Coax Secondary Protection Energy Saving 7 Outlet PowerStrip) consists of one 'Control' outlet, four 'Switched' outlets, and two 'Always On' outlets. It works on the same principles as similar devices I have tested, including the Smart Strip LCG5 and Monster PowerCenter HDP650G. You have to draw a minimum amount of current or power from the 'Control' (or 'Master') outlet, before all four 'Switched' (or 'Slave') outlets can power on. Once the Master device is turned off, or its current drops below a lower threshold, all Slave devices are tripped off.

One important feature of this TrickleStar power strip is that: it has an easily adjustable switching threshold. The trip level can be selected between Low/Medium/High, which corresponds to roughly 10/22/42W of power. So if your Master device is a big-screen TV, you should select High. But if you use a SFF (small form factor) computer as Master, then you should switch the threshold to Medium.

In comparison, the Monster HDP650G has a non-adjustable trip level that does not work well with SFF computers. The Smart Strip LCG5 is most flexible in that it offers a fully adjustable trip level through a trim pot. But the threshold selection switch on this TrickleStar power strip is easier to understand and more user-friendly.

Another good feature of TrickleStar power strip is that: there is a sliding cover for each outlet. This allows you to cover up any unused outlets for safety. Doing so also prevents dust from entering the opening.

On the other hand, there is one significant drawback:
According to my P4460 Kill-A-Watt Electricity Usage Monitor, this power strip itself consumes around 2W of power whenever an appliance is connected to either 'Control' or 'Always ON' outlet. The same 2W consumption is still there even when the control appliance is in low-power standby mode (under 0.5W). This extra power consumption is quite ironic for an 'Energy Saving' product, since it wipes out part of the potential energy saving. In some cases, it may even result in wasted energy. The Smart Strip LCG5 does not have this problem.

Is this product a worthwhile investment from 'Energy Saving' point of view?

Given the relative high cost of this power strip, one has to ask: "How long does it take for this device to pay for itself"? The answer depends on what kind of Slave devices you use. Most modern electronic devices (such as computer monitor or DVD players) are already Energy-Star compliant. That means they consume less than 0.5W of power in standby mode. So if you plug in 4 Energy-Star compliant appliances as slave devices, your net energy saving is ZERO - because the power strip itself consumes 2W of power.

In my case, I have an old subwoofer that consumes around 5 watt even while not playing music. So by plugging it in a Slave outlet, I can expect to save around 3W x 24hr = 72 watt-hour of energy per day, which translates to ONE cent assuming energy cost of 15 cents per KWh. At the current price of around 32 USD, it will take nearly NINE years for this product to pay for itself. Oh well, at least it serves as a 'feel good' purchase in the meantime.

Aside:
If you don't need the coaxial-line protection feature, you can get the same power strip for less: TrickleStar 180SS-US-7XX Energy Saving 7 Outlet PowerStrip


Philips 423491 11-watt (60-Watt) Ambient LED A19 2700K (Warm White) Light Bulb, Dimmable
Philips 423491 11-watt (60-Watt) Ambient LED A19 2700K (Warm White) Light Bulb, Dimmable
Price: $14.97
17 used & new from $10.00

5 of 5 people found the following review helpful
5.0 out of 5 stars New and improved LED bulb: more light, less noise, March 28, 2014
I have previously tested the Philips 432732 11-watt A19 LED Bulb and liked it very much. The bulb is compact and gives out nearly omni-directional light, making it suitable as replacement for 60W A19 incandescent bulb. The only problem I have is that, when used in a dimmer-controlled light fixture, it emits a faint humming sound. Recently I purchased this Philips 423491 11-watt A19 LED bulb, thinking it is the same model. I was surprised to see the box I received is marked '880 lumens', instead of 830 for the previous version.

In side-by-side comparison, however, the two versions appear to be equally bright. This is because human eyes cannot notice a mere 6% increase in brightness, anyway. See the picture I uploaded to `Customer Images' section, with dimmer at maximum power. The only noticeable difference is that the lamp shade for the new LED bulb appears a little bit brighter. So the increase in luminosity rating does seem to be real.

Electrically, both the old and new bulbs behave exactly the same according to my P4460 Kill A Watt Electricity Usage Monitor: The measured power consumption toggles between 11 and 12W. The power factor starts from PF=0.95 initially, but drops to 0.87 when warm. Apparently the new bulb has exactly the same power converter stage, but it uses LEDs with higher efficacy. That's how it can generate more light with the same power consumption.

In terms of dimming range, the old and new versions are identical. A real improvement is that: the new bulb emits less noise when dimmed. I have to listen closely at 6 inches away, in order to notice the humming sound. It could be just dumb luck, but I prefer to think that Philips has improved the manufacturing process to reduce the noise.

Philips also produces several lower cost 60W-equivalent LED bulbs. But they have their own limitations:
- The Philips 429381 10.5-watt A19 LED Bulb has a semi-directional light output. It is not dimmable.
- The Philips 433227 10.5-watt Slim Style LED Bulb produces omni-directional light, but it makes a loud buzzing sound when dimmed.

Bottom Line:
The new Philips 11W A19 LED bulb is compact and gives out omni-directional light. It works well in dimmer-controlled light fixtures without excessive humming. Therefore I can recommend this new Philips bulb as a universal replacement for 60W incandescent bulbs.


PureSpectrum 20W Fully Dimmable Spiral CFL 2700K 6000 hours (75W Equivalent)
PureSpectrum 20W Fully Dimmable Spiral CFL 2700K 6000 hours (75W Equivalent)
Offered by The General Store!
Price: $6.41

1 of 1 people found the following review helpful
3.0 out of 5 stars Great in energy-saving, but not quite 'Fully Dimmable', March 25, 2014
I purchased a 2-pack of this PureSpectrum 20W Fully Dimmable Spiral CFL back in August 2010. The two bulbs have been in service in my dining room for over two years, until one bulb finally burned out in November 2012. I have replaced the burn out CFL with a Feit Electric 13.5 Watt LED Bulb and found the latter to be a better product. This is because:

- Although this CFL bulb is advertised as "Fully Dimmable", it does not dim all the way down. When the dimmer switch is at minimum, the CFL is still at (probably) 20% brightness. The new Feit LED bulb, on the other hand, gives a much wider dimming range. See the photos I uploaded to 'Customer Images' section, and you'll know what I mean.

- The first CFL bulb burned out after around 27 months of service. Assuming 5 hours of usage per days, that comes to just about 4000 hours runtime, instead of '6000 hours' as advertised. In contrast, most LED bulbs advertise 20,000 - 30,000 hours of lifespan.

Don't get me wrong, those CFL bulbs were great products when I bought them over three years ago. Over its lifespan, I must have saved at least $25 from each CFL bulb (see footnote section on how I arrived at this number). So I have no regrets buying those. It's just that over the past several years, LED bulb technology has advanced and prices have came down significantly, so now they are better choices for dimming applications.

[Footnote]
Here's how I calculate my saving for each CFL light bulb:
- The PureSpectrum 20W CFL bulb generates 1200 lumens of light output, which is equivalent to a 75W incandescent bulb. The power saving is therefore 75-20=55W.
- Total energy saving over 4000 hours is 55W * 4000h = 220KWh
- Assuming electricity cost of 14 cents per KWh, total saving in energy cost is $30.8
- Ordinary incandescent bulb has a lifespan of ~1000 hours, so in 4000 hours I would need to replace the incandescent bulb 4 times
- Cost of 4 incandescent bulbs = $4 (I'm only guessing here since I hardly bought any incandescent bulbs in the past 10 years)
- Initial cost of CFL = $9 (when I bought them back in 2010)
- Total saving = $30.8 - $9 + $4 = $25.8 per bulb after 4000 hours


Samsung MicroSDHC 32GB Class 10 Plus UHS-I Memory Card
Samsung MicroSDHC 32GB Class 10 Plus UHS-I Memory Card
Offered by Everything But Stromboli
Price: $22.25
31 used & new from $15.21

5 of 5 people found the following review helpful
5.0 out of 5 stars Measured Read/Write speed much FASTER than advertised, March 21, 2014
I grabbed this Samsung MicroSDHC 32GB Class-10 PLUS UHS-1 memory card during an Amazon Gold Box deal, since the price was too good to pass. This is the first Samsung memory card I own, so I was curious to see how it ranks against all my exiting microSDHC cards. Short answer: At the very top.

I used a benchmark program called "CrystalDiskMark v3.01 x64" to measure, among other parameters, the Sequential Read and Write speed of this card. Note that the card reader I used is the Transcend USB 3.0 Card Reader (TS-RDF5K), plugged into an USB 3.0 port. This is important because if you use an USB 2.0 card reader or USB 2.0 port, the maximum speed will be severally handicapped.

Here are my results:
- Sequential Read speed = 79.55MB/s, which exceeds the advertised '48MB/s' by 66%.
- Sequential Write speed = 21.44MB/s, which is more than twice the minimum requirement of 'class-10' (10MB/s)

The above results compare favorably against my fastest card, the SanDisk Extreme microSDHC. The Samsung card is 33% slower in Sequential Write (21.44 vs. 32.1MB/s) but 69% faster in Sequential Read (79.55 vs 47.0MB/s). It should be noted that the Sandisk Extreme is priced nearly 2x higher than the Samsung.

When compared against the most popular microSDHC card in its price range, the SanDisk Ultra UHS-1 MicroSDHC, there is no contest: Samsung blows Sandisk out of the water with 64% faster Write speed (21.44 vs. 13.09MB/s) and 2x faster Read speed (79.55 vs. 40.02MB/s).

(See the chart I uploaded to 'Customer Images' section for comparison against several other brands of microSDHC cards)

Bottom Line:
As of this writing, the Samsung UHS1 microSDHC card is available at nearly the same price as the Sandisk Ultra UHS1 microSDHC card, but it offers significantly higher Read/Write speed. That makes the Samsung card a much better value.

Side Notes:
- The Samsung memory card is made in Korea, as expected.
- The capacity of this '32GB' card, as reported by my computer, is just 29.2GB*. This is slightly below average compared to that of my other '32GB' cards, which range between 29.3 and 29.9GB.
(*Note that computer people count one 'Gig' as '2 to the power 30'. So 1GB comes to 7.37% larger than 1 billion bytes)
Comment Comment (1) | Permalink | Most recent comment: Apr 2, 2014 9:06 AM PDT


Uniden 16-Mile 22 Channel Battery FRS/GMRS Two-Way Radio Pair - Black (GMR1635-2)
Uniden 16-Mile 22 Channel Battery FRS/GMRS Two-Way Radio Pair - Black (GMR1635-2)
Price: $23.81
128 used & new from $15.12

1 of 1 people found the following review helpful
4.0 out of 5 stars Simple-to-use and Kids-Friendly Walkie-Talkies, March 18, 2014
Those Uniden FRS/GMRS Two-Way Radio Pair (GMR1635-2) are so compact, you can easily hold both in one hand. They are also very inexpensive, so one may think of them as just toys for kids, But in fact they can be used by kids and adults alike - provided that you start with the correct expectation.

First of all, forget about the manufacturer's claim of '16-mile' range. That is only possible under the most optimistic test condition (transmitting from one hill top to another with clear line-of-sight). In an urban environment, you are lucky if you can get one or two miles. With this limited range in mind, this walkie talkie set can still be very useful in many places (such as in a National Park, or a large shopping mall). The sound quality is quite decent - similar to an AM radio.

Next, this thing is a battery-eater if you use disposable alkaline cells (three AAA per radio). The manufacturer claims an average battery life of '20 hours'. But again, this is under a special test condition of '5/5/90', which means 5% transmit, 5% receive, and 90% idle time. The device consumes different amount of current during different operation modes, as shown below:

- While transmitting: 400mA
- While receiving: 50-100mA (depending on volume level)
- While idling: around 15mA.

If you do a lot of transmission, a set of alkaline cells is likely to run flat in less than two hours (because alkaline cells are very inefficient at high current). My advice is to buy some good quality AAA rechargeable cells (such as Sanyo Eneloop) to power those radios. That way, not only will you save money on batteries, you can even get longer run time per charge.


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