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What multimeter would the masses recommend?
I would like one for tinkering with batteries and bike lights etc, but I figure I might as well get something half decent as it's the sort of thing I'll only buy once.
Rough budget 30-60 quid - what should I get?
Fluke.
You won't get a fluke in that price range, go for a iso-tech, we use them at work and they work well.
I've had one of these for years, proved to be reliable and easy to use
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http://www.uni-trend.com/en/product/2014_0801_925.html
Pretty much any will do it. Even the £5 ones are ok. Just get with a good on/off switch so you don't accidentally knock it on in your tool box and flatten the battery.
I think I'd like one that auto ranges. I was looking at the uni-t ones (which look ideal) but I think I'd have to import. Nothing decent domestically within that range?
I got a Vichy VC97. Easy to find on Amazon or ebay, has way more features than any I've had before and was about £25. Review of it and similar here : http://www.robotroom.com/Multimeter-Reviews-2.html
This will be plenty good enough:
http://www.maplin.co.uk/p/uni-trend-ut30b-digital-compact-multimeter-used-b53nz
But I suspect you want something like this:
http://www.maplin.co.uk/p/uni-trend-ut60e-rms-autoranging-digital-multimeter-with-pc-interface-n81cb
or
http://www.maplin.co.uk/p/uni-trend-ut60a-autoranging-with-pc-interface-digital-multimeter-n80cb
I do a lot of electronic stuff, so use mine a lot. I have a cheap £5 job from Maplin which works just fine - no particular need for anything more fancy. Autoranging is overrated - 99% of the time I know exactly what range my measurement is going to be in and it's hardly any more trouble to switch to the correct range than just to switch it on - I mean if you're measuring the voltage on a bike battery you know roughly what it's going to be.
I might go as far as to say that is often a bad thing. When you circuit is doing something odd (and that is often the case by the time you get the meter out) then having the meter hunting for a range makes it harder to track.Autoranging is overrated
I should point out that I also do electronic stuff professionally, so get to use fancy expensive Flukes, and whilst I'd not use a £5 Maplin meter in work, that's mainly because it's not been calibrated rather than that it's lacking in features (and informal testing suggests the calibration is close enough for anything I use it for).