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A hard to resist problem

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I don't get it. Why are there "curves" on this meter? Supposed to be sexy?
:happy: Yus, just like de ladies

I'm with you Keep, especially where style impedes function, an extreme example cars, but good styling has benifits. Rounded corners and edges make the instrument less likely to suffer damage and a curved shape, so long as not taken to the extreme, can make an instrument easier to handle, easier to clean, and easier to put in a pocket or case.

My old digital multimeter, although still performing well, is fine for bench work but, because of its square edges, is not so good in the field.

One of the nicests instruments was the traditional moving coil Avo8 multimeter- at one time, if you didn't have one you were not allowed in polite company. Nice as they were though, they were easily damaged, mostly because of the Bakalite case, but partly because of the square corners. They were also bad to handle due to the boxy shape. There were much better and cheaper multimeters at the time but, like Fluke now, Avo were the gold standard. I expect you had an equivalent gold standard in the US, Tailor perhaps?
 
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I was a Simpson 260 guy for years. Sadly, lost it (in a fit of stupid betting) back in the late '90s... :arghh:.

Still like an analog (traditional moving coil), though, for very short, low rep rate pulse detection, like a LM567 output when I'm frequency scanning. I know a 'scope will do that, but setup is way easier with the meter.
 
Bring back memories?


Simpson260_490pix.jpg
ETO_2016_01_01_AVO_Model_8_510pix.jpg
 
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And I have used, many Avo 8s and 9s :)

I'm tempted by this:

**broken link removed**

But I would only be buying it for old time's sake
 
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So I can now confirm that the jaycar resisters are 1/4 watt. I tested the ebay ones in a 6v circuit that I would normally use the jaycar resisters in and it didn't heat up at all so I'm going to assume that they are 1/4 watts.
IMG_1947.jpg
 
It's a beaut; same as an Extech EX540: http://www.extech.com/instruments/product.asp?catid=48&prodid=530

If that instrument had a Fluke badge on it, it would probably cost around the £400 UK mark

I would like to know who the OEM (Own Equipment Manufacturer) is. I'm not sure that Extech are the OEM. If you come across any clues could you post. I suspect Brymen, who would be the most likely, but your multimeter differs from any of their models. It could be a special though. If you are back at the Jaycar store anytime could you see if they know?

By the way, you can get manuals, software updates, etc from the Extech site.

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EC&M 2010 Product of The Year Award
Extech's revolutionary EX540, a waterproof/dustproof, CAT IV wireless datalogging multimeter has been selected as the 2010 EC&M Product of the Year Category Winner for the Portable Measurement Equipment category. According to EC&M magazine, 99 products were evaluated by a panel of judges representing electrical engineers, contractors, and plant facility personnel.
Read More...
Oh wow it looks almost identical :eek: I'll have to ask them who made it the next time I go there to pick something up and see what they say
 
I don't get it. Why are there "curves" on this meter? Supposed to be sexy?

==

EEVBLOG https://www.eevblog.com/forum/chat/u1253b-or-u1252b-or-ex570-or-ex540/ rips the EX%$) apart.

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I think you made a good choice. You lost on accuracy and warranty. No big deal at this point in the game. Just remember when voltages have to be within 5%, in your case, it probably means 6%.
One bright side -- The more buttons means people won't borrow it. At least I found out that to be the case. They don't borrow RPN (Reverse Polish Notation) calculators either. My Fluke 77 (my first digital meter) doesn't have half the functionality that one does. Blew it up once!

One other comment - Don't measure anything stupid: e.g. the output of a spark plug.
I think it's for comfort or at lest that what I tell myself.... XD

Thanks I didn't realize how much I needed it till I got it home and started using it. I know I won't get the most accurate meter for under $150 but for now I think it should do what it needs to do. I can't afford to let anyone borrow it so I'll probably get a dremel and engrave my name into it. I need a dremel anyway so I'll just have more of an excuses to do so without getting in to much trouble with the misses ;)
 
Do me a favor and check out Proxxon See

The Proxxon stand has been re-designed.

The Dremel drill press is a joke. My take is that the Dremel has more attachments.

I actually have a Dremel and a Proxxon stand. The Dremel will fit on a Proxxon stand with a Proxxon press to Dremel tool adapter from Austrailia.

I'm in the process of adding an x-y table
 
Oh wow it looks almost identical :eek: I'll have to ask them who made it the next time I go there to pick something up and see what they say
Hi Justin,
I'm fairly certain now that your multimeter is manufactured by Extech
 
So I can now confirm that the jaycar resisters are 1/4 watt. I tested the ebay ones in a 6v circuit that I would normally use the jaycar resisters in and it didn't heat up at all so I'm going to assume that they are 1/4 watts.

Justin,
Afraid your test is not valid- just put the resistor in question across a voltage without the LED to establish what power makes the resistor surface temperature = around 70 degrees C

Power = (V*V)/R
 
Justin,
Afraid your test is not valid- just put the resistor in question across a voltage without the LED to establish what power makes the resistor surface temperature = around 70 degrees C

Power = (V*V)/R
Okay I'll give it a shot. but so far 6v does nothing and if I use your formula (6*6)/470= 0.0766 (3sf) if that's what you mean. But would you be able to explain the use of the formula please?
 
Okay I'll give it a shot. but so far 6v does nothing and if I use your formula (6*6)/470= 0.0766 (3sf) if that's what you mean. But would you be able to explain the use of the formula please?
The power dissipated in a resistor in Watts = the voltage across the resistor squared divided by the value of the resistor. Your calculations are exactly correct. With 6V across a 470 Ohm resistor, the resistor will be dissipating 0.0766 W as you rightly say. That is 76.6 mW so you would not expect many resistors, apart from the very small microwave types which look like a spec of dust, to get hot.

To establish the power that a resistor family will take to just meet the finger test, you need to vary the resistance value, if you can't vary the voltage that is. To do this you need the formula R= (V*V)/W. As you appear to have a fixed 6V supply this can be substituted to R=36/W. Just keep trying lower and lower value resistors until you reach the point of no-touch. Then calculate the Watts dissipated and you have the wattage rating of the whole resistor family.

As has been said before, there is much more to resistor power rating than this, but for early work stick to the finger test and you will be safe. Incidentally, the finger test is good for all components. A thorough development engineer has his index finger calibrated against an international temperature standard every six months or so because hard skin can build up and mask the readings.
 
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Talking about power supplies, now that you have an excellent multi meter that will meet all your future needs- unless you do some really specialist stuff- the next move would be to sort out your power supplies. Once that is done, assuming you have soldering facilities, you will have all the fundamental tools to do some simple electronic work and you will be able to move up to some real serious projects, especially as you seem to be a fast learner and have a logical approach. You also don't seem to mind making mistakes. Those are all the characteristics needed to succeed in electronics.
 
The power dissipated in a resistor in Watts = the voltage across the resistor squared divided by the value of the resistor. Your calculations are exactly correct. With 6V across a 470 Ohm resistor, the resistor will be dissipating 0.0766 W as you rightly say. That is 76.6 mW so you would not expect many resistors, apart from the very small microwave types which look like a spec of dust, to get hot.

To establish the power that a resistor family will take to just meet the finger test, you need to vary the resistance value, if you can't vary the voltage that is. To do this you need the formula R= (V*V)/W. As you appear to have a fixed 6V supply this can be substituted to R=36/W. Just keep trying lower and lower value resistors until you reach the point of no-touch. Then calculate the Watts dissipated and you have the wattage rating of the whole resistor family.

As has been said before, there is much more to resistor power rating than this, but for early work stick to the finger test and you will be safe. Incidentally, the finger test is good for all components. A thorough development engineer has his index finger calibrated against an international temperature standard every six months or so because hard skin can build up and mask the readings.
Oh wow that is interesting! I'll keep testing them then. I'll also try and use the temperature gauge on my multi meter too.
 
Talking about power supplies, now that you have an excellent multi meter that will meet all your future needs- unless you do some really specialist stuff- the next move would be to sort out your power supplies. Once that is done, assuming you have soldering facilities, you will have all the fundamental tools to do some simple electronic work and you will be able to move up to some real serious projects, especially as you seem to be a fast learner and have a logical approach. You also don't seem to mind making mistakes. Those are all the characteristics needed to succeed in electronics.
Hmmm... Power supplies are a bit pricey but I think I'll either go for this one https://www.jaycar.co.nz/Power-Prod...t-Switchmode-Laboratory-Power-Supply/p/MP3800 as it's cheap but it's also variable or this one https://www.jaycar.co.nz/Power-Prod...ted-Variable-Laboratory-Power-Supply/p/MP3086 As it seems a little bit more user friendly but a bit more expensive. Any thoughts?
 
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