Audio Project Amplifier Speaker Loudspeaker Kit
diyAudio.com diyAudio Forums Archive > Top > Other Stuff > Electronics and Parts
 
Any decent, used DMMs (bench/hand) <£70? - Click HERE for Original Thread
Triophile
Evening.

Well, I've finally reached that point (known as common sense, I believe) where I've had enough of cheap, rubbish DMMs, and am looking to invest in something a bit better. I've got a capacitance meter and an LCR (both handheld and fairly cheap), so I won't need my new meter to handle those.

I'm after something which will measure AC volts over a reasonable bandwidth (actually, what is a good bandwidth that would cover analogue and digital equipment? Is it better just to use a 'scope for checking voltages in digital gear?) I've had a poke around on DIYA, and Flukes invariably come in for recommendation, but are there other makes and models worth considering?

I've poked around and had a look at some of the older Fluke bench DMMs (8050A, for example) which seem to run from about 20Hz up to 20kHz. Any other suggestions for something which will hold its calibration (or be relatively cheap to re-calibrate)? I'm happy to spend less than £70 as I'm pretty skint, but if I have to be flexible on budget, so be it - no more cheap rubbish!

Cheers, Jon.
AudioFreak
To put it simply there is Fluke and then there is everything else. The HP / Agilent Lab test gear is also worth having a look at.
bluesmoke
Hmmm...

I've seen the Tektronix "Tek Meter" for a decent price on ebay a couple of times recently. Not sure if it's what you're looking for, but looks quite handy as an integrated scope/meter. Doesn't seem to measure current though.

The HP's seem decent too.
x-pro
Have a look here:

http://www.stewart-of-reading.co.uk/sor_dmm.html

There are some interesting offers and it is easy just to go there and pick what you like most. I've used them in the past and got some nice gear there.

For instance: Solartron 7150 (some descripion and photo here:

http://cgi.ebay.com/ws/eBayISAPI.dl..._PCN_BIX_Stores ) for £75 .

Cheers

x-pro
Triophile
Thanks for your replies.

x-pro, that Solartron on the Stewart's site was one of the meters I was looking at, though I couldn't find any info on the web about its bandwidth in terms of measuring voltage (the Fluke that's also on there has a bandwidth of 20Hz-20kHz, I believe). It's good to know they're a reliable supplier, as I tend to be a bit cautious with companies I've never encountered before. I was mulling over getting that Lutron frequency counter too.


Bluesmoke, I'd love to get a scope meter, but is that within my budget? I've not heard of the Tek Meter - I'll have to check it out.

Cheers, Jon.
bluesmoke
Hi,

It basically depends on the TekMeter that is available (they've got some going for several grand). Saw quite a nice basic version going for $125USD on ebay just last week (kicked myself for not bidding, but don't really have the needs or funds at the moment)..

There's a new one up... search for...

Tektronix THM565 TekMeter True RMS Multimeter

Right now the bid is at $63 USD... I'm sure it wil climb, but it has a good chance of staying within your budget.

Take a look, and best of luck (I hate eBay... always outbid)
AuroraB
In terms of accuracy, there is ususally nothing wrong with instruments from e.g. Metex, Meterman etc. etc. - all the medium priced ones..
We have all our lab gear calibrated once a year, and usually throws in a handful of "toolbox" type meters....calibration is always OK. Even most of the cheaper ones will possibly calibrate OK.

The safety aspect in working with power electrics can be quite another story. I saw a test a few years ago, where a selection of multimeters where tested- set for amps measurements and then exposed to 220V-
some of the very cheap ones literally blew up! - The Flukes had a blown fuse..... Some of the cheaper ones only have fuses for the milliamp ranges.....
Drop tests also often kills the cheap ones....

I tend to agreee with AudioFreak... there's Fluke- a small handful of others -and all the rest.....
The choic e is yours... but OTOH- what is your need ..???
Nigel Goodwin
quote:
Originally posted by Triophile
I'm after something which will measure AC volts over a reasonable bandwidth (actually, what is a good bandwidth that would cover analogue and digital equipment? Is it better just to use a 'scope for checking voltages in digital gear?) I've had a poke around on DIYA, and Flukes invariably come in for recommendation, but are there other makes and models worth considering?


As you're looking for audio bandwidth I suggest you consider an AC millivoltmeter, the correct tool for the job, rather than a multimeter?. A scope is also extremely useful, far more so than a multimeter that covers audio bandwidth!.
quote:


Any other suggestions for something which will hold its calibration (or be relatively cheap to re-calibrate)?

Don't get carried away about 'calibration', it's NOT about accurate calibration, and it's NOT that meters need regularly calibrating, it's just to provide CERTIFICATION - a paper trail, basically that's the sole reason for it!.

For home use, and the vast majority of professional use, it's a waste of time and money.
AuroraB
I'm not saying you need calilbration at all, - most and even cheap ones are quite accurate, - and rarely have any drift.
The reason for calibration today is certification, -- and not to skimp at - trustability for the user, professional or hobby. A lot of people seem to think that the cheap instruments are inaccurate, but this is generally not true. An easy way to check, is to borrow one or more from friends, and just compare - calibration to official standards is very expensive.

I may have been too hasty, because I did not see the original poster looking for bandwidth....this is another point which separates the chickens from the cocks. Measuring AC voltage can be a tricky bussiness.
Most instruments reads some mean value, which is OK for sine, True RMS is a different story. In this case I'm afraid you have to dig a lot deeper in the pockets- or stay tuned to Ebay.......

BTW- pawn shops, second hand and companies specialising in realization of property after bankrupcies might be another source....
Ones death - anothers bread...
Triophile
Bluesmoke, I wish you hadn't mentioned that Tektronix THM565 - I wanted one as soon as I saw it. I'll keep an eye on the others there and see what they go for.

Thanks for the comments about calibration - sounds as if it's not really something I'm going to need to bother with (or, more importantly, spend money on).
bluesmoke
Yup,

Definitely a tempting piece of gear. Hope another pops up soon for you.

Page generated in 0.036447048187256 seconds with 17 queries,
spending 0.00794220 doing MySQL queries and 0.02850485 doing PHP things.

Powered by: Search Engine Indexer and vBulletin
Copyright ©1999-2008 diyAudio.com