Archive for March, 2011

Oyster Card Hacking

An Oyster card, as described by Wikipedia, is:

a form of electronic ticketing used on public transport services primarily within the Greater London region of England. It is promoted by Transport for London and is valid on a number of different travel systems across London including London Underground, buses, the Docklands Light Railway (DLR), London Overground, trams, some river boat services and most National Rail services within the London Fare Zones.

This describes how to extract the RFID chip from an Oyster card.


  • Oyster card
  • Acetone (commonly found in nail polish remover)


    • Submerge card in acetone until it softens.
    • Peel off layer of plastic and submerge again.
    • Repeat until chip is visible.

The wire for the antenna of the chip is very fine so it’s easier and quicker to extract the chip without it and opt to solder on your own antenna. The contacts on the chip are quite weak so care has to be taken not to break them off (They look like wings on either side of the chip. Should be easy to spot if you look at where the aerial connects to the chip). Encasing the chip in something like hot glue will help prevent the antenna detaching. For what it’s worth, the aerial in the card is about 13cm with 5 loops long but you may need to experiment a little to make a working replica.


Sun 20 Mar 2011 01:35:52 UTCSun 20 Mar 2011 01:40:50 UTCSun 20 Mar 2011 01:49:58 UTCSun 20 Mar 2011 04:43:48 UTCSun 20 Mar 2011 22:21:58 UTC

Light Ring

Decided to attempt to make a basic light ring that could mount onto a Nikon D80 equipped with a lens wearing a HB-32 hood.


36 white LEDs mounted on a ring of acrylic that would wedge onto the HB-32 hood (which has a mid-point diameter of ~80mm). The power source (4xAA batteries) would mount onto the Nikon D80’s hot shoe mount along with brightness and off/on controls.


  • A3 5mm acrylic = £5.40
  • 5mm white LED (30,000mcd) (£0.64) x 36 = £23.04
  • SPST rocker switch (£0.41) x 1 = £0.41
  • AA battery holder(£0.14) x 2 = £0.28
  • 10K potentiometer (£0.57) x 1 = £0.57

Total = £29.70

The acrylic was cut using a laser cutter with design that was created in Inkscape:

Light Ring Design


Sun 13 Mar 2011 21:47:44 UTCSun 13 Mar 2011 21:55:29 UTCMon 14 Mar 2011 21:26:56 UTCMon 14 Mar 2011 21:18:06 UTC

Return top


Shinkutanku; Japanese for “Think Tank”. A very infrequently updated blog by your average code-monkey cum photographer.

Twitter: @CiaranEaton