Board Thread:The Reference Desk/@comment-4139960-20130611213836/@comment-188432-20130612144512

Our page is clearly wrong. Seven uses a sonic screwdriver in around 15 of the NAs. But it's also used most inconsistently in the NAs.

He tells the Brig, "It's a replacement. I only had time to make a new one very recently," in No Future. But that's NA23, and he's quite unremarkably described as casually looking for it n NA2. Meanwhile, in NA11, he's wondering why he "never got round to building another sonic screwdriver". By NA12, though, the sonic screwdriver is there in full flower, and is even a kind of MacGuffin for a part of the plot of The Pit.

In NA30 there's this notion that he has the sonic back, but only because he got it from the parallel Earth of NA19, even though Blood Heat doesn't describe such a scene, and even though this makes no sense with respect to the televised understanding about the Doctor as having the ability to make sonic screwdrivers at will. (Seriously, why would he need to get a sonic from a world overrun by Silurians, when Eleven pops 'em out of the TARDIS console like toast? Or indeed, why would he need any version of Earth, when NA25 posits that they're perfectly ordinary tools on Mars?)  GodEngine, NA51, has yet another notion, suggesting that he got it back because he "sued the Terileptils for criminal damage". And, as if it weren't already an almighty affront to continuity, Lungbarrow — NA 60 — offers up the notion that Romana II is the source of the TVM Seventh Doctor's sonic, gifting him what is ostensibly her model from The Horns of Nimon.

So there's three different "origin stories" for Seven's sonic – never minding the fact that the sonic appeared with little comment in NA37 43, 44, and 56.