Personal Ultrasonic Air Cooler for the Smart Apartment

With the hot weather and smoke in South Eastern Australia, I needed a little personal cooling in the Smart Apartment, so I put a small low voltage ultrasonic humidifier up in front of a low voltage electric fan.  The humidifier produces a cloud of water droplets (looks like fog), and the fan blows it to me, making a cooling breeze. This is much more effective, and safer, than hanging a wet cloth in front of a mains powered fan.

Mini Travel Humidifier

I have a Beurer LB12 Mini Air Humidifier, from Appliances Online. This is similar to the Elechomes Ultrasonic Mini Cool Mist Humidifier, available on Amazon.These units run on low voltage, from a mains plug-pack. You use a plastic bottle as a water tank: fill the bottle, screw on a one-way valve and upend the bottle on the unit. A small bottle of water lasts a couple of hours. When the water runs out, the humidifier turns off.

Mini USB Personal Fan

I use a 12 volt fan from a computer, connected to a mains plug-pack. But if you don't want to worry about connecting wires, you could use a Mini USB Personal Fan.

Power Bank as a USB Data Blocker?

The May edition of TechLife Australia in their security and privacy guide laments the lack of available "USB Data Blockers". Perhaps a USB Power Bank can be used as a data blocker.

The problem is that a USB cable can transmit data as well as power. LifeHacker suggests the use of a USB Data Blocker when using USB devices you are not sure of. The Data blocker plugs in between your device and the untrusted device, to let the power through, but no data. However, they can't find any commercial source of such devices.

There are some USB Data Blockers offered by Amazon.com, such as the PortaPow Data Block,
but these are not commonly available in retail stores.

In contrast USB Power Banks are readily available at low price. These have two USB sockets: one to charge the power back and one to charge your device from the power bank. A discussion in Whirlpool suggests some power banks can be plugged in to a power source and device to charge simultaneously. If this "pass-though" mode stops data, the power-bank can be used as a data block.

USB To 12 Volt Power Supply

A low cost "USB to 12V Step-up Power Module" can be used to run a 3G wireless router, from the USB socket of a laptop computer. This should work for other low power electronic devices, saving having to carry around several mains power adaptors and allowing devices to be run away from mains power from the laptop battery. It also allows running 12 Volt devices from the same USB mains adaptor used for 5 Volt devices.

The module is from  Canton Electronics, and is sold on eBay for US $5.45 (including international postage). The module arrived in Australia within two weeks of ordering.

The module consists of a small circuit board attached to a USB plug. The board has two screw terminations for attaching the supplied 5.5mm DC plug, via a short cable. The screws on the board are very small and I had some difficulty loosening one of them to attach the cable. It is very important to get the polarity of the cable correct (red wire for "+" positive terminal, for a positive tip on the plug).

First I tried the module wil a USB plugpack, as I did not want to risk damaging my computer. The module provided 12.2 Volts, with no load (measured with a multimeter).

Connecting the supply to a Huawei D100 3G Router showed a load of 160 mA without the USB Modem installed. With the Huawei E220 USB wireless modem installed, the router shut down. But this was not a problem with the module, but the plug-pack, which cannot supply enough power. Plugging the module into my laptop, the router with modem drew 200 to 330 mA.

I left the module running all night and it was working fine in the morning and did not feel warm to the touch. The module has no case, so I wrapped it in self-amalgamating tape, to protect it.

There are a few improvements which could be made to the module. One would be to supply the module with the cable already attached. Another would be a case for the module. Also the cable could be a bit longer (the one supplied is about 300 mm), I suggest 500 mm (the same length as the shortest commonly available Ethernet patch cables).

One question I have with the module is what it is actually for. The maker's description says "Home Automation Solar charger". This does not make a lot of sense, as a solar panel is unlikely to be putting out 5 Volts, nor have a USB socket . If this was instead described as a "USB to 12 Volt power supply", provided with a case and a slight longer cable, it could be a popular unit.

ps: It has taken me five years to find a USB To 12 Volt Power supply (an attempt to use a 9 volt one did not work). If setting out to do this today, a simple alternative is the TP-LINK Wireless-N Mini Router (TL-MR3020), which is powered by a USB cable and is only AU $49 RRP.

Power for Traveling in Singaport and Sri Lanka

On a recent visit to Singapore and Sri Lanka I had the problem of how to recharge my laptop and phone. Both Singapore and Sri Lanka, being former British colonies, use UK power plugs, with large square pins. But Sri Lanka also uses a round pin plug. So I purchased Australian to UK and Australian to European power adapters.

The UK (BS 1363 Type G) adapter worked fine until I left it behind in a hotel. The problem was that the adapter, like most, was the same off-white color as a power point, thus easy to forget. I suggest buying a black one, so it looks like part of your computer power cable.

The next problem was the two different power plugs in Sri Lanka. The capital city, Colombo, seemed to use the UK plug, whereas the rest of the country had a three pin round unit. This looks a little like the European power plug but is not quite compatible. The three pin round sockets are not European ones, but a derivative of an old UK standard (BS 546 or Indian IS 1293).

I found I had to buy a local power adapter for Sri Lanka. There are adapters readily available for about $US2, but these are of questionable safety. The adapters are designed to take UK, European, US and Australian plugs. They have so many and so large holes in them that the plugs are not held firmly and large sparks can be seen when contact is lost.

In Singapore I purchased a Lifetrons 10.5W Travel Adaptor FG-2102PD. This is almost a cube with a US/UK,European and Australian socket on one side  and plugs for the same folding or retracting into the other sides. It is bulky and cumbersome looking but works okay. The unit is black and when plugged into my laptop cable it looks neat. It also has one high power USB socket and so can be used to charge a phone at the same time.

Android Smart Phones for Military Use

The article "Infantry Innovation" Daniel Wasserbly, Janes Defence Weekly, 24 August 2011), discusses how the military can use smart phones on the battlefield. Mobile phones have been heavily used in support. Where there is no cell coverage available, mobile cell towers with satellite links can be used. Now consideration is being given to using the phones on the battlefield.

One option is to have a low power device to relay the mobile phone signals into the military radio network (much like the pico-cells now available for householders to boost mobile coverage). But this creates considerable security and support issues.

A simpler option is to use the smart phone as a terminal to the existing military radio. In this case the operator slips their civilian into a cradle with a cable plugged into a military radio. As well as providing power and data interface, the cradle protects the phone from damage. This approach should work well with the current crop of smart phones.

Smart phones (apart from the Apple iPhone) now mostly use the same standard micro-USB connector, for both charging and data. The connector is generally at the bottom centre of the phone, but some have it on the side, so a plug on a cable would be needed. It should therefore be possible to make a one-size-fits-all cradle to fit smart phones. This cradle would have an oversize case with a flexible transparent window on the front, like the Aqua Box Waterproof Smartphone Cases, so the touch screen can be used. Such a unit would be much larger than the custom cases for phones but still much more compact than the typical purpose built military terminal. The case would also be very cheap, being able to be mass produced, and sold for less than $100 retail. A similar, but larger case could be made for tablet computers.

There is much discussion in military circles of software development kits for running military applications, such as the US Amry Mobile/Handheld Computing Environment (M/HH CE). But the basic use for the smart phone will be to act as a web browser to remote applications. This requires no additional software and the same applications can be sued on tablet computers, smart phones, laptops and desktop computers.

Securing Flash Drives with Lanyards

It was reported in "Defence investigates lost and found memory stick" that a defence contractor left a flash drive containing classified documents on a commercial aircraft (Secure Computing, 14 March 2011). A simple way to prevent this is to attach the flash drive to lanyard, or a retractable reel, as issued to staff for swipe cards. For those needing something more robust there are retracting lanyards designed to secure a fishing knife, such as the Rewind Gear Retractor.

For those needing something even stronger, there are coiled lanyards designed for military personnel to secure their handguns, such as the Tactical Pistol Lanyard, Coil Black.

Low cost computer security device to replace passwords

Greetings from the famous room N101 at the School of Computer Science at ANU. Bob Edwards is presenting on "Yubikey Authentication in a Mid-sized Organisation". This is a preview of paper for Linux Conference of Australia 2010 (LCA2010) in January.

The Yubikey is a low cost ($10) security token designed to replace passwords for computer access. It is a small USB unit designed to be attached to a key ring and inserted into a computer when access is needed. The device generates a 44 character pseudo random number when a button on the unit is pressed. It emulates a keyboard to send the number to an application. The device uses AES-128 bit encryption.

One use which has been poposed is Yubikey identifying airline pilots on the U.S. Department of Homeland Security Transportation Security Administration blog.

Yubikey provide an online authentication server, which can be used. However, as Bob points out, this requires you to trust the security and reliability of Yubikey's system. Yubico allow for the device to be reprogrammed with a new 128 bit key so that an organisation can run its own authentication server.

One limitation of the device is that it has no internal battery and so cannot keep track of time. As a result the tokens generated never expire. Also as with any token, it must be kept physically secure. If left in a computer (as happens with sensitive devices), it will provide access for the next person who happens along (although an additional user entered id and password could be used).

Other limitations of the device are that it requires a USB port. Allowing USB devices to emulate a keyboard creates a security problem, but if disabled would stop the Yubikey working. Also, because it emulates a keyboard, any application on the host computer can read random numbers generated by the Yubikey.

One option which might be interesting for Yubico to make a credit card sized Yubikey. This would have sufficient space to overprint as identity card and have a conventional magnetic stripe. This could then be used with existing standard identity card printers and magnetic stripe security systems for student and staff ID cards. There are a number of designs available which have a USB interface on the edge of the card, or in a flexible cutout or with a folding card. These may seem cumbersome and subject to failure, but I have had a SanDisk Ultra SD Card for some years, which folds in the middle to covert to a USB drive.

Yubico might like to market the devices for green ICT power saving. The host computers could be programmed to switch to low power mode unit the device is inserted. It could also be used with thin client devices where the user's application run on a server. When the device was inserted in a different client, the applications would be restored as they were when suspended.

The Swedish company Yubico manufacture the Yubikey One-Time-Password (OTP) USB device and have released all protocol and other relevant details which makes the Yubikey particularly attractive as a low-cost and non-vendor-lock-in authentication solution.

Bob will demonstrate the Yubikey for the purposes of secure authentication on untrusted end-user systems (eg. PCs at an Internet Cafe or a friends house etc.) and will discuss some of the advantages as well as some of the weaknesses of the Yubikey system. He will then go on to describe the development of an authentication server written in C and based on a PostgreSQL database and implementing LDAP and other authentication protocols. This will include some technical details of how to use the APIs for connection to the database, parsing the ASN1 LDAP queries, dealing with denial-of-service attacks etc. He will also discuss some of the code he has written to implement the Yubikey protocol on devices with no USB port (eg. a PDA or mobile phone etc.).

This talk is a prelude to a paper Bob will present at the Linux Conference of Australia in 2010 (LCA2010) in Wellington, NZ in January.

BIO:
Bob Edwards is the Chief IT Officer in the School of Computer Science at the ANU. He also teaches into the Computer Networks course and the Free and Open Source Software Development (FOSSD) course, amongst others.

From: Yubikey Authentication in a Mid-sized Organisation, ANU 2009

Getting 9 Volts from USB

The "USB Mobile Phone Adaptor Kit" I ordered from Swamp Industries turned up in the mail the next day. The kit is impressive, with both car and mains USB adaptors to supply power and assorted plugs for differnet phones . However, the USB Adaptor, which boosts 5 Volts from a USB socket to 9 Volts, does not supply sufficient current to run my Huawei D100 3G Router and HUAWEI E169 3G USB modem.

The modem with the US wireless 3G modem plugged in uses about 270 mA, which should be just within what the USB adaptor supplies (300 mA +-5% at 9 Volts). However, the router uses up to 500 mA for a few seconds when it first starts up. When I turn the router on it starts to boot, then the green light on the USB adaptor turns red (presumably to indicate it is overloaded) and the modem goes off.

One good point is that the adaptor doesn't seem to be harmed by the overoad and is able to protect itself. So I did a quick calculation and decided that a 80 uF capacitor would store sufficient power while the router boots (the calculation involves Amps, Volts, Watts, Jules, and Farads). So, in theory, if I connect the capacitor (which will cost about $2) across the power terminals of the DC supply from the USB adaptor and wait a few seconds before turning on the router, the capacitor will be charged up with enough power to supply the router when it starts and it should then run fine.

If there are no more postings for a few days, that will be because my netbook has blown up, while trying this. ;-)

Powering a 12 Volt Router from USB

Connecting the HUAWEI E169 3G USB modem to the Kogan Agora Netbook is proving harder than expected. While there are descriptions on the web of simply plugging the modem in and restarting the computer, the Kogan does not seem to recognise the device. Some manual modifications of setting have not helped. So I decided to take a different approach: when plugged into the Huawei D100 3G Router the modem works fine with the Kogan. The settings for the modem are stored in the router. This has the added advantage of the firewall in the modem and that the device can be shared by several computers.

But the router runs on 12 Volts from and mains power supply. How would I use it when away from a power socket when the Netbook is running on batteries? My first thought was to run the router on the power from a USB plug of the computer. I found that the Kogan's USB sockets supply plenty of power, being able to run an external DVD drive or hard disk. With my previous laptop I had to use two USB sockets to get enough power for an external drive.

The catch is that no one seems to make a USB to 12 Volt adaptor (there are plenty of 12 Volt to USB adaptors). In fact there are numerous web postings saying this is not possible. It is possible, but needs extra electronics to turn the 5 Volts supply by the USB socket into 12 Volts.

Not being able to find a 12 Volt adaptor, I thought I would make the problem easier by trying a lower voltage. Most digital electronics actually run on 5 Volts or less. The 12 Volts supplied to equipment is converted down. So first I tried the router at 5 Volts, using the USB adaptor cable which came with the external DVD drive. This was after I checked the voltage and polarity of the power with a multimeter). This did not work, clearly more than 5 Volts was needed.

Previously I had run a router designed for 12 Volts on a 9 Volt supply, with no problems. So I tried this with the Huawei D100 3G Router and found it works fine on 9 Volts (it has been running for 12 hours this way).

So then I looked for a USB to 9 Volt adaptor. There were numerous queries about such devices on the web and replies saying it was not possible. But I found one about a "USB Power Supply for Video Sunglasses" which used a DC-DC converter (voltage converter) from a phone charger accessory kit described as a "9V Nokia Booster for Wireless Phone Charger".

The booster is a small black box with a USB plug on one end and a USB socket on the other. The device converts 5 Volts to 9 Volts at 300 mA and is designed for charging old Nokia mobile phones. The instructions warn this should only be used with a 9 Volt device: plugging a standard 5 Volt powered USB device into the unit could damage the device.

As I already had a USB adaptor from the DVD which plugs into the router, it should be a simple matter to plug the voltage booster into the Netbook, plug the USB adaptor cable into that and that into the router. But where in the world do I buy such an adaptor and how long will it take to get to Australia?

As the device was for a Nokia phone, I looked at the Nokia catalogue, which had a "Nokia Charger via USB port CA-100". However, this appeared to be for newer phones which use a lower voltage. I looked at Ryda, who sell a "Nokia CA-70 USB Data Cable with Intergrated Charger". This looked more than I needed and I was still not sure it would supply the needed voltage.

After more searching I found the "Charger Sony K750 W830c w958 Z558 M608 W300 J220 K310" offered on Ebay by Swamp Industries. This appeared to be the same adaptor kit as used for the video sunglasses. I checked to see the company details on the web to see how long this would take to import into Australia and found the company is based in Canberra (where I am). Also I found the kit includes an Australian mains to USB power adaptor, which would be handy. On the company's own web site the kit is described as "Universal USB Mobile Car Wall PC Charger Nokia, Blackberry" and was half the price on the company web site as on eBay. So I ordered one.

It will be interesting to see when it turns up. It is also curious that having searched the world online, I found the product I wanted offered by someone a few kilometres away. I was tempted to phone the company and ask to collect the unit in person, but this is probably a part time mail order company with no shop. I do have the satisfaction of having a name to put to the company, as when I paid via PayPal, the system gave me the person email address of who was getting the payment.

USB standards for mobile phone chargers

The use of USB for mobile phone chargers should reduce materials and energy use as well as costs to the consumer. Since 2007, China has required mobile phones to use a USB interface for the battery charger. As of 2010 the European Union will require a micro-USB connector on mobile phones for charging.
The Chinese and European requirements are different but compatible. The Chinese requirement is for a USB Type A socket on the charger. The EU requires a micro-USB connector on the phone. So to meet both requirements would require a charger with a USB Type A socket, a micro-USB to Type A USB Cable and a phone with a micro-USB socket. The Chinese requirement would slightly increase the cost, as an extra plug and socket is needed at the charger end of the cable.

The EU requirement is only for data enabled phones, the ones which are likely to have a USB socket anyway. While this has been described as only applying to high cost smart phones, there are many low cost phones which have a USB interface. As an example the Motorola U9 sells in Australia for $99 and comes with a micro-USB socket. Unfortunately the U9 comes with the micro-USB plug permanently wired to the power adaptor. The Australian Motorola adaptor is not compatible with the Chinese standard as it does not have a Type A socket.

Instead of having to buy a charger with each phone, the one charger can be shared between different brands and models of phones. In a household were each person previously had a charger plugged in for each phone, instead one charger can be used. This will use less energy as only one charger will be consuming power.

These standards will also make it easier for consumers, with fewer different chargers and cables. The USB cables are low cost. A Type A to Micro USB cable from Paddy's Markets in Sydney, for example, is $12.

Harmonisation of a charging capability of common charger for mobile phones - frequently asked questions

(see also IP/09/1049 )

What's the issue?

Incompatibility of chargers for mobile phones is a major environmental problem and an inconvenience for users across the European Union. Currently specific chargers are sold together with specific mobile phones. A user who wants to change his/her mobile phone must usually acquire a new charger and dispose the current one, even if this is in perfect condition. This unnecessarily generates important amounts of electronic waste.

Which is the solution envisaged?

Harmonising mobile phone chargers will bring significant economic and environmental benefits. Following a request from the European Commission and in close co-operation with the Commission services, major producers of mobile phones have agreed in a Memorandum of Understanding (“MoU”) to harmonise chargers for data-enabled mobile phones sold in the EU. Industry commits to provide chargers compatibility on the basis of the Micro-USB connector. Once the commitment becomes effective, it will be possible to charge data-enabled mobile phones from any charger compatible with the common specifications.

Who will benefit and how?

Consumers will not need to buy a new charger together with every mobile phone, and they should also benefit from more efficient and cheaper stand-alone chargers. Consumers will be able to charge their mobile phone from the new common charger.

The environmental benefits of harmonising chargers are expected to be very important: reducing the number of chargers unnecessarily sold will reduce the associated generated electronic waste, which currently amounts to thousands of tons. Harmonised chargers are also expected to improve energy-efficiency, thus reducing energy consumption.

What will be the impact of the MoU on prices?

Consumers will be able to purchase mobile phones without a charger, thus logically reducing their cost. They will also be able to purchase much more cost-effective stand-alone chargers than it is currently the case

Are all mobile phones covered by the MoU?

The MoU covers data-enabled mobile phones. The MoU excludes mobile phones which do not support USB data exchange and also certain unusual formats of phone, for example phones worn as wristwatches.

Which is the agreed common interface?

On the basis of the Micro USB interface, the companies have agreed to develop a common specification in order to allow for full compatibility and safety of chargers and mobile phones

Why does the MoU only apply to data-enabled mobile phones/equipment?

Mobile phones are short-life products. It is expected that from 2010 onwards most future mobile phones will be data-enabled.

When is the proposal likely to come into effect?

It is expected that the first generation of new inter-chargeable mobile phones will reach the EU market from 2010 onwards. The Commission will closely work with industry in order to facilitate an implementation of the agreement on the market as soon as possible.

Which companies have signed the MoU?

The following 10 companies have signed the MoU:

• Apple

• LG

• Motorola

• NEC

• Nokia

• Qualcomm

• Research In Motion

• Samsung

• Sony Ericsson

• Texas Instruments

Where does the MoU apply?

The MoU covers the territory of the EU. However, as the market for mobile phones is essentially global, the MoU should be seen as a good model for other geographical markets. The Commission is committed to sharing this approach with its trading partners, in order to extend its benefits world-wide.

From: Harmonisation of a charging capability of common charger for mobile phones - frequently asked questions, Media Release, European Union, Reference: MEMO/09/301, 29/06/2009

EcoButton Energy Saver Gets Mixed Reviews

The EcoButton is a large backlight button which you plug into a computer via USB. Press the button and the computer is put in a low power suspended mode, press it again and the computer wakes up. This idea has got mixed reviews. On the one hand the device doesn't do any more than can be done with built in functions in the computer (my laptop has a suspend/resume button already or you can do the same thing with a few mouse clicks). The device will use extra resoruces to make and use. On the other hand having a dedicated on/off switch, by being simple and convenient, might be used by people who would otherwise leave their computer on. At least this is better for the environment than a USB cup warmer.

UK Government Data Missing on Memory Stick

A USB flash drive with tens of thousands of prison and police records on it is missing in the UK. Perhaps Jacqui Smith, the government minister responsible, should have the contractor (PA Consulting) purchase some heavy duty retractable reel lanyards to secure the flash drives. When a similar incident happened in Australia with a military officer leaving important data behind, I jokingly suggested that military personnel should be issued with a retractable cable clipped to their uniform. The officer could then clip the flash drive to the other end of the cable. If they forgot the flash drive, the cable would pull it out of the computer and retract when they got up. Reels with nylon cable are commonly issued to staff with security swipe cards, but the clips and cables on most are flimsy. So I found on Amazon.com a stainless steel lanyard sold to sailors for attaching then penknives to. These are much stronger than the nylon cables and they have a secure steel clip on each end. While this started off as a joke, I found that people were ordering batches of these lanyards, presumably to hold flash drives. So I created an Amazon.com store for lanyards. For those needing more security there are coiled plastic cable lanyards. Smaller ones of these are designed for divers and have a stainless steel clip on each end. Even stronger units are pistol lanyards. Some of these are actually a steel cable coated with plastic. One end of the cable has a wide nylon loop for attaching to a belt and the other a thin loop or a clip. They are designed for military and police handguns. One manufacturer claims that the cable is so strong it can help stop an attacker turning the gun on the owner. Because the lanyard is attached to the butt of the gun, the tension of the cable makes it naturally point away from the holder. As a result it is difficult for someone to point the gun at themselves or for anyone else to do that. The military lanyards are more than would be needed for holding a flash drive, but then for security personnel, this sort of lanyard might fit better with their uniform than a shiny stainless steel reel. To complement this, there are also Waterproof USB Flash Drives. See the Amazon.com store:

1. Retractable Lanyards
2. Coiled Lanyards
3. Pistol Lanyards
4. USB Flash Drive
5. Waterproof USB Flash Drives

Real uses for flash drive lanyards

It was reported May 17, 2006 that a senior military officer left a CD containing a confidential report in a computer in the at an airport lounge:

... today it emerged Brigadier ... left the results of her investigation in a computer in the Qantas Club lounge at Melbourne Airport on Monday.
Defence Minister Brendan Nelson told reporters he was "angry and disappointed" by the latest bungle, and said he had not seen a copy of the report. ...

In response I wrote a spoof press release about a fictional product:

"... reinforced military specification lanyard which can be attached to a flash drive, or other removable electronic memory device. The other end of the FlashHard is secured to the uniform of the personnel responsible for the information. The FlashHard will first provide a warning if the user attempts to leave their workstation without removing the flash drive. If the user ignores the warning, the FlashHard will automatically eject the flash drive from the workstation and retract it onto the user's uniform. ...".

It turns out that this is a real use. My brother, Dr. John Worthington, is an Educational Consultant and Psychologist, dealing with children. One problem is with some children leaving flash drives in PCs at school. So he suggested they be attached to a retractable reel, as used by staff for swipe cards. As in my spoof release, the drive is tethered to the child. After a few weeks of reminders from the device, the child gets into the habit of checking the flash drive before getting up.

Perhaps this would also work on military personnel, but they may still want a more military looking unit. ;-)