See also: Plugs and Sockets Bonanza

The 3.5mm headphone jack is essentially a 19th Century bit of kit – it is a miniaturised version of the classic quarter-inch jack (6.35mm), which is said to go back as far as 1878.

(http://www.bbc.co.uk/news/magazine-35253398)

Mike Jordan

Surprisingly techie for them and almost all correct but no mention of difference between PO316 and 1/4” or what ever 6.35mm is and I am sure the bit between Tip, Ring and sleeve isn’t an “insulating cable” (maybe insulation).

Interestingly their photo of what may be an iPhone does seem to have an adaptor to jack on the end of a cable – more bits to break and need expensive replacement?

Pat Heigham

Yes, there are two dimensions for 1/4" jack plugs. The ‘A’ and ‘B’ versions.

One has a smaller tip, which makes a mating lock more dodgy as it’s the groove behind the tip contact that makes it secure (if you are trying to mate a small tip to a larger socket).

While the article is pretty accurate, I did come across Western Electric 35mm Magnetic film installations which wired the tip to be ground, on the basis that if dangling ‘double-enders’ touched the chassis of the rack, nothing disastrous happened.

Nick Moore

They failed to point out that the iPad / iPhone uses a 4 pin TRRS 3.5 mm jack, to carry microphone, stereo headphones and common ground. They also failed to point out that the apple lightening connector only carries digital signals, so the headphones will need a built in D/A converter, making them unique and undoubtedly exclusive to Apple and at Apples very inflated prices.

John Howell

However they did say "… Certain modern plugs have a second ring to allow control of a headset microphone or volume…."

Bernie Newnham

My Nikon D7000 takes a four pin 3.5mm jack so that one ring can carry video. I didn’t realise this and wondered why on earth there was this endless buzzing when monitoring the audio.

Dave Mundy

… as does my Mini DV Panasonic camcorder, the other end of the cable has yellow, red. and white phono plugs (RCA) to connect to my Panasonic DVD/VHS m/c or TV.