Friday, 5 December 2008

Experiment Update (10)

sensor readings

The phone setup is as follows:
Phone Mode: Flight Mode
Data Connection: Bluetooth Serial Port Emulation- COM9
Battery Status: Discharging

Experiment Update (9)

Promising!! Now for the third round of testing!

Experiment Update (8)

Temperature still falling slowly. I get the feeling that somehow the GSM is still enabled (due to the signal quality indicator) but that it is not attempting to 'lock on' to a network by sending out request packets / signals.

Experiment Update (7)

The phone setup in the prior experimental updates was:
Phone Mode: Normal
Data Connection: Bluetooth Serial Port Emulation- COM9
Battery Status: Discharging

I have just finished setting up the USB connection and the phone is now back outside.
The phone setup is now:
Phone Mode: Flight Mode (GSM Disabled)
Data Connection: USB Serial Port Emulation- COM3
Battery Status: Charging

Several questions come to mind:
1) Does charging the battery generate any heat? (Likely answer is yes).
2) Which services/peripherals are really disabled when the phone is put into flight-mode?
3) Will the steady state temperature of the two temperature sensors be lower than before? (Unsure as more than two of the test conditions have been changed i.e. not a strict manipulated/responding relationship between switching the phone from 'normal mode' to 'flight mode' and observing the effect on steady-state temperature).
I propose third round of experimentation (which suits my need to procrastinate more than anything else) in which I enable Bluetooth whilst in flight mode (removing the USB connection) so as to isolate the effect of disabling the GSM from the incidental heating which may result from the fact that phone is transmitting it's data via USB rather than bluetooth.

Experiment Update (6)

I just saw the phone temerature drop to 1*c whilst the battery temperature remains at 4*c. So whilst the battery temperature sensor was more quick to react to the environmental temerature (presumeably because it is on the periphery of the device unlike the internal phone sensor), the phone temperature sensor is giving a reading which is consistent with the area forecast for this area.
The elevated temperature of the battery could be explained in one of two ways:
1) The temperature sensor is out of range because 1*c is below the recommended operating temperature for the phone.
2) The power dissiapted across the battery is sufficient to maintain a steady-state temperature of 4*c.

I will bring the phone inside, turn off the GSM by putting it into flight mode in order to reduce the power consumption (and, hopefully, the power dissipation over the battery) and then sling it back out again . If this allows the steady state temperature of the battery to stabilise to a lower level then I am prepared to favour hypothesis 2 over hypothesis 1.

Experiment Update (5)

I think the experimentation is done for tonight. Not only because the temperature seems to have stabilised but also because it is currently my main phone... Ironically, despite just having written the above and uploading the screenshot, the phone temperature has just dropped to 2*c whilest the battery temperature remains at 4*c. Maybe I will leave it to dangle a while longer...

Experiment Update (4)

I did not think to put in my postcode first time round (which is odd for me).
It turns out that searching 'XXXXXX  forecast' (where XXXXXX is my postcode) returned a much different result than searching 'Durham forecast'. I must reserve my judgement on which is the more accurate temperature data... One must also bear-in-mind that the temperautre of the phone is likely to be a funcation of: the ambient temperature, the thermal mass of the house, local heating/wind/shielding effects, dissipation of heat across components.
Further experiment may include: Test with GSM disabled. Test with Bluetooth disabled.
Also, I think it would also be interesting to compare these results to a high-precision Mecury thermometer.

Experiment Update (3)

No sooner had I posted and the temperature had fallen to that of the forecast! When I get a new phone (possibly at christmas). I can think about what use I might put my dear old K610. I think that sealing it in a water proof bag with silica gel bags and a long usb extension (rather than bluetooth) would make it a very good outdoor temperature probe. If I combine that with the time-lapse webcam data then I might have a reasonable, independant, indication of local weather conditions. Now all I need is my final year project to be finished and I can really get into sensor netwokring on a grander scale. Oh it will be sweet. For now, I am having evil thoughts about stripping back some of the form factor to see if that allows the temperature sensors to react more quickly.

Experiment Update (2)

Nearly there!

Experiment Update (1)

The charger started whining so I unplugged it. As you can see the temperature is continuing to fall. I am interested to see if I can plot some graphs from this data. I would also love to know if the phone can log this data locally and if it would be possible to sync at the end of each day?

Phone. Dangle. Bluetooth. Sensor. Cold.

So I was messing around with MyPhoneExplorer- I established a Bluetooth link and am currently charging the phone (the chord of which also conveniently serves as a tether by which to dangle the phone out of the window). I don't like my phone that much anyway. But in the interest of science, seeing if the temperature readings can actually be reflective of the environment the phone is in, it is a small price to pay to have my phone dangle out of a window. After all, it is kind of in a protective casing. The idea for the test occurred when I was thinking of ways to put off doing my C coding assignment due in tomorrow. I was playing with Bluetooth in anticipation of receiving my wiimote (to make my own multi-point interactive display inspired by this work: and I came across the 'Monitor' function under the 'Others' group in the MyPhoneExplorer software. I googled the current forecast for temperature tonight and have been occasionally looking in at the temperature. Let's see if the phone temperature reading tends towards the forecast.
Currently, batt temp: 13*c and phone temp: 17*c. Looking good!

Saturday, 15 November 2008


I take it back. There is support. There is firmware. I stripped the NAS down to the main external casing and the main circuit board. What I found was the following:


Jackpot. A bit of googling and 2 minutes later...


So now I know the name of the device.

Then more googling:

So now I know the specs of the device.

Then, on the same site, I found the GPL:

and also a link to a new firmware release from the company.

Hello NAS, Nmap -O

I have been trying to figure out how I can interact with my new NAS.
It was a bargain at ~£30 from Aria's bargain basement.
Whilst it does what is says on the tin it also has some bad points:
1) It is unbranded w/ No obvious support or documentation.
2) The firmware looks like it was made in the 60's. (However I know this to not be true...)

I would love to move away from using the ancient webpanel and start interacting with it from the CLI. This the is output from nmap -O

:~$ sudo nmap -O
[sudo] password for samuel:

Starting Nmap 4.53 ( ) at 2008-11-15 15:56 GMT
Interesting ports on
Not shown: 1706 closed ports
21/tcp open ftp
80/tcp open http
111/tcp open rpcbind
139/tcp open netbios-ssn
445/tcp open microsoft-ds
515/tcp open printer
668/tcp open unknown
3689/tcp open rendezvous
MAC Address: 7A:B4:F5:00:0A:D3 (Unknown)
Device type: general purpose
Running: Linux 2.6.X
OS details: Linux 2.6.11 - 2.6.22
Uptime: 0.035 days (since Sat Nov 15 15:05:15 2008)
Network Distance: 1 hop

OS detection performed. Please report any incorrect results at .
Nmap done: 1 IP address (1 host up) scanned in 3.938 seconds

Monday, 20 October 2008

Final Year Project- Wireless Sensor Networks


just getting my teeth into my final year project.
The original title was: Very Small Short Range Radio Transceiver.
Although the project has now been given an application so the focus is more on wireless sensor networks (WSN).
I have been reading two books on the subject:
Networking wireless sensors / Bhaskar Krishnamachari

Wireless sensor networks : architectures and protocols / Edgar H. Callaway

So far they have both been useful in gaining an insight into the main limiting factors of wireless sensor network technology. Chief among which is network lifetime. This can be viewed in one of two ways.
1) The ability of the batteries to store enough energy to keep the network online.
2) The ability of the device to save power or minimise consumption to the point where energy is only being expended when strictly necessary to maintain network operation.

The first problem is not one which I will be able to tackle within the scope of this project although the choice of battery technology and the way in which the power is drawn from the batteries does require some careful consideration. For example, although many batteries might have a certain mAH rating, when they are loaded this rating, effectively, tends to fall as the load increases (due to heating effects and, presumably, some other effect of which I am not yet aware). Thus, if the instantaneous current being demanded at any given time can be reduced, I believe that more power can be drawn from the battery because the system is operating in a higher-efficiency region. I.e. thinking to when the radio transceiver becomes active and the power consumption rockets by upwards of ~36mA above the base current required to power the circuitry. If I can charge, perhaps, a capacitor or use some kind of low current drawing circuitry, then maybe it will be possible to reduce or minimise the effect on the battery life due to these inefficient regions of energy consumption. Before I get too ahead of myself I may just go and ask my project supervisor if this effect is likely to be significant. Heaven forbid, I might actually take the initiative and do the sums/look into it myself!
Thoughts of the day:
What do mobile phones do to combat this peak in current demand when on an active call?
What other power-saving strategies do they employ?

Friday, 26 September 2008

MIT OCW and Wikinomics

I am still awake, and now blogging, because of a bit of bed time reading of "Wikinomics" by Don Tapscott (Author) and Anthony Williams (Author)- On page 23 I was reminded of MIT's Open Course Ware (MIT OCW). I was quite excited to look for engineering related resources and I was not disappointed. After visiting the site, I remembered an email that a friend had sent to me.
It turns out that I was originally introduced to this resource by a friend as this excerpt from an email shows:
Subject: Have a look at this
Date: Tue, 13 Nov 2007 01:43:20 +0100

Look at this

Audio, Video lectures from engineering to literature, plus lecture notes.

A general site

For example

Video lectures on circuits and electronics:

Mp3 files on Advanced Digital Integrated Circuits:

May just border the scope of your second year material, tell what you think.
I can only say thank you. I seemed to not go for it on first bite but I am just glad that another path has brought me back to the same information but this time with fresh eyes (well...not so fresh at 1am...). I just watched lecture 16 on 'Sinusoidal steady state' (additional videos, accompanying notes etc. can be found on this page). The lecturer's style and delivery was refreshing to say the least. I really enjoyed it. One thing I noticed about his style was the abundance of mental anchors to allow the teaching points to embed themselves into the memory.
It seems funny to me that while this precious resource was presented to me back in Nov 2007 it has taken me until now to come across it again on my own terms and realise it's full value.

But back in Nov 2007 while I was interested in open source, I was obviously not fully aware of it's significance in (my) education. Nearly a year on I am glad to say that, for example, I use delicious as my principle research and indexing tool and evernote as my notebook for just about everything. These have both added enormously to my education allowing me to build huge and complex webs of tagged and indexed notes, references and links. Suffice it to say that I am glad to think differently now.

Monday, 22 September 2008

The good old days

A picture from the good old days! I hope to be reusing some of these computers to create some dedicated onion routers, file servers, ssh tunnels, webservers etc. Don't worry, I will put Linux on them. I would not trust XP to run as a server. Ubuntu all the way for those that can, and those that can't will take xubuntu or equiv low-spec OS. TBH it might be a case of: the processing power is not worth the electrical power the PC is consuming. So maybe I should content myself to have lots of large metal doorstops instead?
I also need a serial interface electrical switch / relay / control unit so I can bring my 32 port netgear router or a smaller 5 port one online when I need it (or for that matter anything else that plugs into the mains). I wonder if there is already a standard interface for doing such things. If I am not satisfied with what I find, I will make one from scratch as a project.
Back to the servers, I hope to be able to employ WOL magic packets to use the 'Wake on Lan' capabilities of the NICs (Lan Cards) to bring the computers online as and when I need them (to save some more power).

Hello Blogsphere!

This is my first blog post. I will start by introducing myself:
My name is Sam and, on the date of publishing 22/09/08, I am soon to be a third year electronic engineering student.
I applied to Durham to read General Engineering and now that I am a third year I have to option of 'streaming' to focus on electronics.
One of the main benefits of the General Engineering course is that I have been able to give each major discipline a fair shot at capturing my imagination. Well, it seems that electronics has won.

I am probably going to be one of about eight electronic engineering students (it seems to be a less popular choice). I am staggered that this is the case given the current trends towards complete global connectivity and the increase in computing power in the home. I fear that so many people will fail to engage with the technological innovations of the 21st century and simply be left in the dust. But I know by now that technology is not everyone's cup of tea. Oh well, sucks to be them. It is mine.

I am looking forward to returning in October for several reasons, chief among which is finding a master's course for my fourth year. I will also spend countless hours on my final year project working with low powered wireless modules (like the Jennic JN5139, Till next Blog.