History of the TARDIS...

[Klaus]

...an interesting article about the different versions of the blue box over the years.

http://www.themindrobber.co.uk/tardis-police-box.html

 

[C.E. Evans]

I've always maintained that the TARDIS' chameleon circuit changes into a slightly different blue police box periodically.

 

[Mark_Nguyen]

In "Logopolis", that's exactly what the Doctor was trying to do manually as part of his idea to fix the chameleon circuit. Later the Eleventh Doctor claims upon every single landing, the TARDIS automatically changes... Into the same police box.

Mark

 

[Sindatur]

In "Logopolis", that's exactly what the Doctor was trying to do manually as part of his idea to fix the chameleon circuit. Later the Eleventh Doctor claims upon every single landing, the TARDIS automatically changes... Into the same police box.

Mark

Six had it "working" for a couple episodes

 

[Captaindemotion]

Wow, I don't usually get too interested in details like the different sizes or shapes of the TARDIS (it's always looked like a blue box to me) but it was actually a surprise to see just how much variety and how many shapes and sizes it has come in over the years. Nice article, thanks for posting.

 

[Christopher]

In "Logopolis", that's exactly what the Doctor was trying to do manually as part of his idea to fix the chameleon circuit.

Well, no, he wasn't trying to change it into a different police box... he was trying to take the exact measurements of a real police box as a baseline so the Logopolitans could diagnose and repair the chameleon circuit. It was kind of nebulously explained, but the idea was that the real police box he measured had to be identical to the shape of the TARDIS, so that its dimensions could be "overlaid" on the TARDIS, and... something. Maybe it was meant to be a control against which they could compare the simulation (i.e. the TARDIS exterior), thus revealing something about the workings of the chameleon circuit or exposing its flaws or something.