To realize an INSTRUMENT

I have the schema of an instrument.I am looking for some one to realize it. I AM NOT an electrician. Who can help.Thank You to all

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Noureddine Melal
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What do you have in mind?
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John Fields

t. I AM NOT an electrician. Who can help.Thank You to all

I hope the design is mot some sort of super secret because you are going to have to show it to determine the best way to proceed. If you want only one , making the circuit board can be quite expensive, and actually - is the ci rcuit board already designed ? If you have proper artwork in 1X (size) a ph optosensitive board is not a big problem, but the holes are. In fact before the advent of SMDs if you asked a circuit board maker for a quote one of t heir first questions was "how many holes ?". More SMDs would probably help keep the cost down, but then it is usually better to use a two sided board. That's if that part of it is not layed out yet.

There exists a machine that can mechanically etch out one board. It is pret ty much a plottter with a Dremel tool attached, but of course more involved . Costly. What that means is if you find somebiody with one it will probabl y be cheaper that one who uses a chemical method. However it will still not be cheap because this thing is expensive and requires some fairly involved software. Some software might be able to design the board as well.

There is more to it than just breaking out a soldering iron and ordering th e parts. Another thing to consider is the case/cabinet. Off the shelf optio ns are not all that attractive without a bunch of modificatiion and nobody is going to make a $300,000 mold to build one unit. Then it depends on how big it is.

For example I have been procrastinating about building my own ESP meter of my own design. I think I can outdo what is on the market, at least ad hoc m y purpose and that of others doing certain types of work. If I ever get aro und to it I will probably find a regular digital voltmeter that's screwed u p and use its case. I'll just have to make my circuit board conform to its dimensions. If everybody loves it and wants to buy one then I will probably buy replacement cases for something that is currently available. A nice ru gger Fluke DVM case would fit the bill.

Then the power source. That is not etched in stone. If it is to run off bat teries do you want rechargeable ? That part will probably have to be design ed on the fly. If you want to use dry cells do you want AA, AAA or 9V ? All have advantages and disadvantages. It also depends on how much power the t hing consumes of course.

So to get good answers, the question must be complete. We need to see the p rint (schematic). It can be in many formats like PDF, DJVU amd I don't know about anybody else but I can view DWG files as well. If there are no files like that just scan it and make a JPG out of it. Upload it to the public d irectory of your cloud storage and drop the link in here as we don't do bin aries here.

If you don't have cloud storage you might want to fget some. Seems like alo t of people here use dropbox, which works pretty well. I use it myself. It installs clean, no issues, no problems. You get at least a GB free and if t he schematic doesn't fit in that, apply for a government grant before proce eding lol.

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Cripes, ESP meter ? I know I am full of typos but ESP instead of ESR ? Even an eye transplant won't fix that. I am doomed.

Well I guess if I can build an ESP meter I could go around and rate all the local psychics. Anyone got any ideas on how to design that ? Then we get Bob Parker to handle the business end of it.........

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Was "ESP meter" a Freudian slip?

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why not an LCR meter that tells you everything in there? ...all done with SW and your soundcard.

The 'LCR Meter' determines whether the device under test is capacitive, inductive, or resistive then presents you with forms of the model for you to choose - from simple to complex and then calculates the best curve fit to the data for that model

Examples of model choices for a capacitor C series C Resr series C Resr Leff series C Resr Leff, parallel Rdielectric

If you have an accurate AC voltmeter and an accurate sense resistor; you should be able to calibrate then obtain something like 0.05% repeatibility.

Even do in situ cap measurements, by turning the drive down below junction voltage levels, like less than 50mV.

BUT! won't be able to bias a cap with voltage, nor bias an inductor with current - without kludging up those drives.

But come on, soundcard and SW and you're done!

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I doubt a PC based solution would work well for me. Somethng handheld would be best. I don't need a laboratory quality instrument for service, nor do I need one the has a digital readout. The old Creative electronics Wonderbo x has an analog meter so it is not so rugged. A simple bar graph display wo uld be fine as well as easier to read fast.

I was thinking of about a 1Khz positiv going square wave at about 100 mV. T he detector end of it would only respond to the higher harmonics of course which will make it work well on a wide range of cap values.

For quite a time I used the probe calibrator of a scope for this and just w atched the trace. I put a resistor of maybe 390 ohms there to kind protect the generator, a good high value cap would result in a flat line that float ed up to the center of the screen. Lower values would yield varying amp;lit udes of traingle waves of course, but the split between the top and bottom portions indicated the ESR. You could technically read it in ohms I guess b ut it wasn't really necessary. All we needed was a go-nogo. After I taught the others how to read the thing it became a big hit.

Even lower value caps were readable. They would produce like a ½ sine wav e, but you were still looking for the split between the rounded part and th e flat part of the last cycle. Any more detail I will have to draw it. (tho ugh I MIGHT have some pictures somewhere)

Problem is that it was also big and bulky.

Actually, it should be a piece of cake for a DVM manufacturer to just inclu de an AC ohms scale. Just pick the right frequency like 50 Khz. You got AC and DC voilts, you got AC and DC ohms. I'd bet someone already does that bu t I want it cheap and simple.

All I want is a strip of LEDs. No digital, no zebra strip, no microprocesso r, it simply isn't necessary. If you want to plot ESR against temperature a nd generate a graph or whatever like Jeff Leiberman did, then this is not t he right tool. If you want to fix ten SMPSes in TVs in a day, it is.

Waterproof would be nice in case I happen to be consuming my favorite bever age. Oh, I guess that would be beerproof then right ?

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Oops, that is a ¼ sine wave.

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Now that I think of it, if I used a constant current source and sink rather than just resistance it would always be a triangle wave. That would make it easier to read the waveform on the smaller value caps.

Also I think with some tweaking I could make an ESR meter read all the way down to 0.1 uF, but I don't see much usefulness in persuing that.

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