µCurrent GOLD on Kickstarter

[MLXXXp]

Does anyone think an asymmetrical virtual ground would be a good idea?

I'd like to be able to take full advantage of the 2V range of my meter and I rarely want to measure positive to negative current swings. The virtual ground could be shifted downwards to change the ranges from +/-1250xA to between +2000xA and -500xA. Reversing the leads would allow -2000xA to +500xA readings (with equipment ground considerations).

My brain may not be functioning at 100% after last night's New Year's celebrations but I believe that if you wanted to have the same current through the divider, changing R6 to 158k and R7 to 39.2k should accomplish this.

[tszaboo]

I just had a huge WTF moment opening the Altium files, Dave.
You did not give use component numbers, nor BOM. It is not like I want to build one myself, you know it is not economical, I'm just curious. You wrote open hardware there, give us all the information required to make it. Even you said this some 500 videos before.
Several files are "not found" when opening the project.
There is total of 240 DRC errors on the design.
You used a 1206 footprint for the 0805 LED.
Did not include the Library for the project.
You use mils and american symbols on the schematic

[Wytnucls]

One doesn't look a gift horse in the mouth.
If anybody wants to make a uCurrent instead of buying one, Dave would probably oblige and correct errors in the files, if asked nicely.

[con-f-use]

One doesn't look a gift horse in the mouth.

But as Dave himself said, there a requirements to fulfil in order to put the open hardware logo on your product.

[george graves]

I think this is the video you are referring to.  Skip to 2:10



He does mention that the actualy part numbers and BOM should be included.  And I tend to agree.

[Bloch]

You used a 1206 footprint for the 0805 LED.

No problems. I think he did just not change the sch then he did change the part in the pcb file

Did not include the Library for the project.

You dont "need" the library files in Protel

Try Design > Make Integrated Library

No Problem 

There is total of 240 DRC errors on the design.

  That is the problem 

It just means that yous "standard" rules is not the same as Dave's

Take a nap or eat some pills for to high blood pressure 

Dave's files are just fine in MY book.

[EEVblog]

I just had a huge WTF moment opening the Altium files, Dave.
You did not give use component numbers, nor BOM.
It is not like I want to build one myself, you know it is not economical, I'm just curious. You wrote open hardware there, give us all the information required to make it. Even you said this some 500 videos before.
Several files are "not found" when opening the project.
There is total of 240 DRC errors on the design.
You used a 1206 footprint for the 0805 LED.
Did not include the Library for the project.
You use mils and american symbols on the schematic

I have not got around to releasing all the info yet.
I don't do project based libraries. You can generate it yourself from within Altium.

[tszaboo]

I have not got around to releasing all the info yet.
I don't do project based libraries. You can generate it yourself from within Altium.

So, can I look at this as  pre-release. What I was actually looking for are the banana plug types you used, they look so nice.

[Jay_Diddy_B]

Hi,

Franky aka iloveelectronics helped Dave source those connectors in China.

Refer to this message:

https://www.eevblog.com/forum/crowd-funded-projects/current-gold-on-kickstarter/msg349554/#msg349554


Franky's eBay store is: http://www.99centHobbies.com

Jay_Diddy_B

[iloveelectronics]

Hi,

Franky aka iloveelectronics helped Dave source those connectors in China.

Refer to this message:

https://www.eevblog.com/forum/crowd-funded-projects/current-gold-on-kickstarter/msg349554/#msg349554


Franky's eBay store is: http://www.99centHobbies.com

Jay_Diddy_B

Thanks for the plug (no pun intended )! Yes, I sourced those for Dave and I do have some in stock but I haven't had time to list them in my eBay store yet. Please contact me privately if anyone's interested in getting some.

Cheers,
Franky

[MLXXXp]

From a while back in this thread:

How about maximum input currents per range?

[...]
If you really need to know, it's maybe:

10A on the mA range.
250mA on the uA range.
5mA on the nA range.

But those wouldn't be sustainable indefinitely.

Regardless of inherent protection due to increased shunt resistance when switching ranges, and other factors, I'd still like to know what the maximum continuously sustainable safe current would be for each range based on:

- Not exceeding the continuous safe wattage of the shunt resistors

and/or

- Not frying any of the circuitry due to the voltage impressed upon the shunt resistors from the current flow.

This would be for both the µCurrent powered on and off, if it makes a difference.

[idpromnut]

@eevblog:

The questionaire that you sent out for the uCurrents didn't ask if we wanted the cases signed; I assume that you will be signing them all?  If not, I would like mine signed (since I don't know when I will be able to get out to Australia to try and get my Fluke 27 signed )

[EEVblog]

The questionaire that you sent out for the uCurrents didn't ask if we wanted the cases signed; I assume that you will be signing them all?  If not, I would like mine signed (since I don't know when I will be able to get out to Australia to try and get my Fluke 27 signed )

Yes, all will be signed.
First units shipped today!
I wonder if any other hardware kickstarter has shipped on the same day as the money came through?

[u271D]

I'm a backer and I got no questionnaire  or survey?

[VK5RC]

u271D, from the emails I got we will have to wait unit they are just about to be posted as Dave only gets one go at getting the addresses for the group, I think we will get surveyed late Jan early Feb if you are the 200 or so group,
We will have to wait!

[u271D]

Yes one of the 200, I didn't know he could select what people he was sending the survey to. I did remembered that he only had one shot at it; that's why I posted. I thought all the surveys went at once.

[EEVblog]

Yes one of the 200, I didn't know he could select what people he was sending the survey to. I did remembered that he only had one shot at it; that's why I posted. I thought all the surveys went at once.

Yes, I can chose the groups. Kickstarter is actually quite nice at this survey thing, it works well. Too bad you can only do it once. The export function works perfectly. About the only thing I'm quite happy with with KS so far.

[LapTop006]

uCurrent #5 arrived this morning, now to take it back to the lab.

[RobertHolcombe]

Did dave include fudge with the signed units? 

[gdewitte]

The description on Kickstarter notes it can also be used as a precision ×100 voltage amplifier. What's the setup for doing this?

[MLXXXp]

gdewitte,
If you put it on the nA scale, it essentially is a 100X voltage amplifier with a 10k ohm input resistance. If that resistance is too low for you, you would have to remove the 10k shunt resistor.

Note that the maximum usable input voltage would be +/- 12.5mV, for which you would get a 1.25V output. Also note that if you want to get this full output swing even when the battery voltage starts to drop, your output load impedance should be quite high (100k ohm or more, which is true for current measurements as well).

[Rutger]

Personally, I think you should not go near any mailing house again. Get a decent label printer like the Zebra brand, and choose the option of friends and family to prepare the shipments. You can ship them out in batches. You would not only save yourself a lot of headaches, but also some serious money.

[EEVblog]

Personally, I think you should not go near any mailing house again.

Well I do now have myself an Australia Post business account, and I get the same corporate rates as the mailing house, so technically I am now my own mailing house...

[wilheldp]

Personally, I think you should not go near any mailing house again.

Well I do now have myself an Australia Post business account, and I get the same corporate rates as the mailing house, so technically I am now my own mailing house...

Did you have to promise/prove some level of volume to get those rates?  I'm sure the uCurrent Kickstarter campaign is more than enough volume.  I'm just curious if there is a threshold.

[EEVblog]

Did you have to promise/prove some level of volume to get those rates?

Yes, a yearly number.
So if I do end up going with a mailing house and I don't meet those numbers, I have no idea what happens if I don't meet it in a years time.
They also force you into a credit account which I didn't want, so they had to check my financials and trade references. Which is stupid, because in today's ecommerce world you can run a multi-million dollar turnover business and not have a single trade reference.