Graphic-DMM: Digital Multimeter on a CF Card

[Jonathon Watkins]

<div class='os_post_top_link'><a href='http://www.pdatoday.com/more/2224_0_1_0_M/' target='_blank'>http://www.pdatoday.com/more/2224_0_1_0_M/</a><br /><br /></div><i>"The Graphic-DMM is a new concept in test equipment that allows a PDA, Notebook, Tablet-PC and all Systems equiped with a CF or PCMCIA slot to be turned into a dual channel Graphic Digital Multimeter with sophisticated analysis capabilities.....The Graphic-DMM contains 2 independent Digital Multimeters, connected to a Compact Flash type I interface. The DMMs are Galvanically isolated from the CF interface for saftety and the two channels also isolated from each other. Each channel has its own ADC and front-end circuitry..... The Graphic-DMM adds to the functionallity normally found on classic DMMs, in particular it allows sample rates from &lt;1S/s up to 40kS/s on each channel and has a 1Mbit internal buffer (16kSamples pairs) allowing long data record depths and oscilloscope-like capabilities. Using host software it is possible to create a versatile instrument that can perform accurate DC measurements, display signal waveforms and allow triggering and data logging."</i><br /><br /> <img src="http://www.pocketpcthoughts.com/images/web/2003/Dscn2500.jpg" /> <br /><br />In the dim and distant past I seem to remember a debate about why you would want a CF slot on a PPC. Somehow, I feel that debate has been comprehensively settled today. ;-) You just *know* you want to turn your Pocket PC into a fully-functional, dual-channel digital Multimeter. Hacket-Technology (cool name) suggest that the Graphic-DMM could be used for education, in the automobile, petroleum, natural gas, or manufacturing industries etc. In addition to PDAs, with a suitable adaptor you can also use this card in just about any Desktop, Notebooks, Tablet. Two ready-to-work DMM applications are included, while optional Windows CE, Pocket PC, VB, VC LabVIEW and OEM custom applications are available. One fly in the ointment is the price, which is 615 Euros. Ouch. For far more details, see the <a href="http://www.hacker-technology.com/3479/125891.html">Hacket-Technology</a> website. If you ask nicely, they'll even send you the user guide. So, who's going to get one then? :wink:

[Darius Wey]

In my opinion, I think this sets aside a whole new budget for CF-enabled Pocket PCs for the engineering departments of major universities worldwide. But the price certainly is "above the clouds"...not that "university funding" can complain about anyway... :D

When you compare the above image with the one below, it's little wonder which one appeals more. ;)

http://img97.exs.cx/img97/3536/multimeter.jpg

I can actually think of several universities here in Australia that would actually consider replacing their conventional multimeters with this new concept.

[moaske]

I keep thinking out loud: "Wouldn't a card this huge, just break of off it's CF-interface while using it ?" ;)
Holy contraptions-madness batman ! 8)

[ricksfiona]

I keep thinking out loud: "Wouldn't a card this huge, just break of off it's CF-interface while using it ?" ;)
Holy contraptions-madness batman ! 8)

I was thinking about this myself.

The possibilities of this are pretty great since I would think the processing power of the PDA is greater than the usual multimeter. Graphics capabilities would certainly kick-butt allowing for better/different information layout.

However, I don't think I would want to chance frying my PDA by connecting this thing to some high voltage/amp connection. The multimeter is probably better designed to handle 'accidents'.

[lapchinj]

In the dim and distant past I seem to remember a debate about why you would want a CF slot on a PPC.Yeah I also have a little more distant memory of why the PC should need more than one floppy drive or later on when I thought that "The Little PC That Could" really wanted to be was a mainframe when it got a 5 meg hard drive.
Somehow, I feel that debate has been comprehensively settled today. ;-)

You just *know* you want to turn your Pocket PC into a fully-functional, dual-channel digital Multimeter.
I think I'll stick with my Fluke for the near future since they both look the same size :wink:.

[lapchinj]

When you compare the above image with the one below, it's little wonder which one appeals more.
That's my Fluke alright and it looks a little less fragile than one from Hacket-Technology but the same size. The idea is great but the execution is a little fragile as others have also noted.

I can actually think of several universities here in Australia that would actually consider replacing their conventional multimeters with this new concept.
The interface is cool and I know of tool makers like Snap-On that have CF card interfaces for their automobile computer testing products. While this particular configuration of the tester might last in a university settling I don't think that it will go to far in a garage type setting. Maybe having it connect through a cable like a GPS antenna or built into a sleeve (less portable between PDAs though) would work better.

Jeff-

[MaximumPDA]

Well I have a demo unit on the way for review so we shall see how it works out...im hopefull it will be as cool as I think it is.

--Bill

[Jonathon Watkins]

Well I have a demo unit on the way for review so we shall see how it works out...im hopefull it will be as cool as I think it is.

Excellent. Care to share your review thoughts with us when you are ready? :wink:

[PPCRules]

I've been looking for something like this ever since I got my first PDA (Palm Pilot Personal). Too bad about the price. Actually, I'd be satisfied (for a while) with a simple 0-5V ADC IC interfaced to the CF interface; anything to get an analog input into the reaches PocketPC programming tools.

[BevHoward]

>> 615 Euros &lt;&lt;

Must have rethunk this a bit... my query to them returned "495 Euros"

still out of my "rationalization range"

[Don Stratton]

I've been looking for something like this ever since I got my first PDA (Palm Pilot Personal). Too bad about the price. Actually, I'd be satisfied (for a while) with a simple 0-5V ADC IC interfaced to the CF interface; anything to get an analog input into the reaches PocketPC programming tools.

Given there are several PPCs with microphone input capability it should be fairly easy to rig up a simplistic multimeter, although due to limitations of the audio hardware on the PPC it might only be able to resolve AC signals. If it isn't possible to resolve DC signals it would pretty easy to make an analog circuit to adapt and condition the signal into another form, say voltage-to-frequency.

Someone should give this a shot!


--Don

[mysticzzz]

I use a Fluke Multimeter everyday in industial settings. You can drop a fluke and it will still work. If you drop the device pictured, it will probably be damaged. Also eventually it would probably fry your PocketPC. Fluke makes some very impresive Multimeters that act as ocilliscopes, data loggers, process simulators, all in one handheld device. And someone commented on the high price of the compact flash device - My fluke process meter was $600 if my memory is correct. This is an interesting device though, and is an indicator of the future to come. We already have 2 windows CE devices running 2 of our large compressors.

[PPCRules]

Given there are several PPCs with microphone input capability ... it would pretty easy to make an analog circuit to adapt and condition the signal into another form, say voltage-to-frequency.
I have always asked for a line-in jack on PocketPCs. That would open up a whole new realm of applications.

[DGoncz]

I've been looking for something like this ever since I got my first PDA (Palm Pilot Personal). Too bad about the price. Actually, I'd be satisfied (for a while) with a simple 0-5V ADC IC interfaced to the CF interface; anything to get an analog input into the reaches PocketPC programming tools.

Hacker now offers just such a CF card.

[DGoncz]

>> 615 Euros &lt;&lt;

Must have rethunk this a bit... my query to them returned "495 Euros"

still out of my "rationalization range"

It's time to revive this thread!

I have been loosking for a DCA/DCV dual channel DMM for Pocket PC for quite some time now, and found the Graphic-DMM the other day.

It's perfect for the Smart Bike, an unsolicited proposal to DARPA under Objective Force Warrior. The Smart Bike will replace or more likely supplement the proposed "mule". Some of your have read about the MOEPED3 version of the Smart Bike in Usenet.

An ultracpacitor energy storage system stores energy in the Smart Bike as an "electric flywheel" with energy proportional to voltage squared. Analogous to KE = 1/2 m * v^2, this EE = 1/2 C * V^2 lags behind the voltage output by the 600 watt stall, 20 pound generator hub. An inverter provides 250 W of onboard AC distributed by taps on a bit of track lighthing cut to fit the frame. A halogen headlight rides on the track.

To monitor E (energy) and P (power) in the ultracapacitor, measuring V (voltage) and I (current) is all that is necessary. P = VI = dE/dt. The bank stores more than 50 kilojoules and an auxiliary NiCd pack of 10 D cells will store 200 kilojoules. The caps supply 625 A into a short.

With stable AC power on board, powering the Compaq TC1000 and Siemens SX66 will be easy. This hasn't been done yet, but Yeri, Jeff, and I are shooting for a demo at MIT in March 2009.

De Lormes's Topo USA 5.0 and Blue Logger GPS provide NAV, the SX66 provides COM, and Mathcad integrates the two, in desktop trials of the software. A recent paper (not by me) on closed-form solutions to the vehicle traction problem will be entered into Mathcad soon. I already have routines to take height and slope profile date from Topo into Mathcad and predict travel time, human energy consumption, and simulated competition with unaugmented bicycles. Three relevant "eikonals" exist between any points A and B reachable by bicycle; the energy, time, and distance eikonals.

A headlight donated from Dialight by John Viselli, at 8W AC, will replace the halogen lamp for efficiency as soon as a fairing is mounted to the test bike, a Lightning Cycle Dynamics Thunderbolt SWB recumbent that can be loaded, with a bit of a grunt, onto a Metrobus anywher around DC or a Ride On bus in MD. Metro rail allows this vehicle, also. (The electric wheel fully discharges the cap bank during deceleration and on the way into the terminal, so the only risk is the 10 D cells; the same as a good sized boombox.)

It's a huge conversation piece wherever I go, and I will report on the performance of the Graphic-DMM as soon as Hacker replies with a version modified and fused for 16A DC, the current at which the generator maxes out into a short. This is, of course, the same as the motor stall current at the rated 36 VDC.

ftp://users.aol.com/DGoncz/Bicycle/HappyNewYear.wmv

Doug Goncz
Replikon Research
Falls Church, VA 22044-0394