Definitely NOT a Viscount, Electra nor Convair 240.
The visible main gear looks like a Douglas quad - and the small round windows would mean a DC-4/C-54 as the DC-6/7 had square windows.
If I'm correct, then the latest this photo could have been taken would be around 1969, but probably much earlier - a clue to the timeframe might be the livery of the plane, note there's a small stripe above the main window stripe, and the stylised letters similar to this Viscount shot (taken 1959):
Photos: Vickers 816 Viscount Aircraft Pictures | Airliners.net
Later TAA titles had more regular 'square' lettering.