Category: White papers

What is the difference between raisins, currants and sultanas?

Ever wondered what raisins, currants and sultanas were before they were dried out? The answer is simple: Raisins     = dried grapes Currants  = dried grapes Sultanas  = dried grapes Of course it isn’t quite as simple as that or raisins,…

Barbecue gas – butane or propane?

Buying a gas barbecue can be more than a little complicated. You think you have worked out what you want, then you discover there are two types of LPG (Liqueified Petroleum Gas) – Butane and Propane. Not only that, but the gas…

Memory card speed ratings – what do they mean?

SD and CompactFlash memory cards often carry speed ratings but it isn’t clear what the numbers mean exactly. To make matters worse the two card formats use different methods of designating the speeds. Although many devices only take one card type what…

Digital cameras – why sensor size matters

A wide range of sensor sizes are used in cameras today. The size of the sensors is not related to their resolution (measured in megapixels). The smallest, 1/3.6″, has a tiny light-sensitive surface of only 4mm x 3mm. That is…

GSM phone technology

GSM cellular phones use a combination of Time and Frequency Division Multiple Access. TDMA simply means that several stations can share a frequency by taking turns. The difficult bit is making them think they’ve all got the channel to themselves.…