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[John Roberts {JR}]

I got my 400V parts in today, but am just now finishing up on rev 3 layout of the PCB. (you will notice a subtle shape change, and no more LEDs on the back side. )

This time I am paying extra for DHL shipping from China so should be less than 3 weeks this time.  When spending hundreds of dollars for parts, it seems a false economy to not pay $19 for a couple weeks faster turn.

The window is officially closed for adding any more features    I did add pads to mount a neon lamp for 240V indication, but not sure whether this is really needed (or if it works, but it will probably work)..

JR

PS: While few will appreciate this, I managed to do this layout completely single sided, so could be even cheaper in production, but for small quantity you can't even buy single sided PCB... all the proto houses run 2 sided and just etch off the unwanted side.

[John Roberts {JR}]

2 steps forward one step back...

Not great photography, but the new boards fit and work in the new package. Bad news is this one trips the grounded GFCI outlet too, so I need to revisit.

My math says it is less than 5 ma, but the GFCI is not happy so more bench work tomorrow.

JR

[John Roberts {JR}]

SUCESS.... I had make a few more tweaks (as usual I stopped sharing circuit details). 

I now have it working with GFCI.

The picture shows a GFCI outlet wired RPBG, so the power (blue) and ground (top green LED) is lit... (It thinks a ground is present).

The red and yellow LEDs indicate that ground and neutral are hot....when I touch the probe.

SWEET.   

JR

[John Roberts {JR}]

Here is another picture with the bogus commercial outlet tester saying "all good" while the OD-1 is correctly warning about a hot ground.

JR

[frank kayser]

Here is another picture with the bogus commercial outlet tester saying "all good" while the OD-1 is correctly warning about a hot ground.

JR

Very cool.  Any backers/partners interested? 

[John Roberts {JR}]

Very cool.  Any backers/partners interested?

I am not looking for financial backers, and the first company I tried to partner with did not say no, but pretty much went unresponsive. I didn't burn any bridges with them and may reengage after I get further along.

My ideal partner is somebody already in the business, so they have established distribution into the market, and experience with UL safety standards and UL certified manufacturing.

I have declined to apply for a patent, but am now investigating pursuing the UL approval by myself. I am unwilling to sell even onsey-twosey testers myself without UL blessing.

It isn't rocket science but mistakes can get expensive when learning how to do the agency approval dance by trial and error.  I bought the UL standard that covers the existing commercial tester ($400) and deciphered their creative use of the english language (I think).

I need to confirm the insulation resistance test (100M @ 500V), but since I got the tester working with 100M in series with the touch probe by definition it should pass, and by upgrading to 400V semiconductors the insulation testing shouldn't break it.

I can easily check the boxes for the listed tests that the commercial unit does, with some that it doesn't (like RPBG). 

One difficult spec is the mechanical integrity of the plug assembly but by using an already approved off the shelf part, I should be able to use that as a UL listed subassembly. I might even be able to skip that part of the approval testing (one of the three tests). In fact that off the shelf plug maker is next on my list to approach as a high value partner. 

I have more tweaking and testing to do, but it's looking pretty good.

JR

[Jonathan Johnson]

I have declined to apply for a patent...

Have you explored the existing patents for similar devices, specifically for non-contact voltage testers? I'd hate for you to get into trouble for infringing on someone's patent. I realize that the design is entirely your own, but a patent holder with an independent but similar design could still claim infringement.

One of the lesser-realized purposes of a patent, rather than to prevent copycat works, is to prevent someone else from filing a patent on the same technology thereby preventing your own use of your design. Proving that your work is "prior art" in the face of a false patent claim is likely to be expensive and difficult when you don't already have a patent.

If you really don't want to file for a patent, then it may be in your best interest to open-source the final design. That will help to establish the design as "prior art". Alternatively, you sell the design to a manufacturer and let them patent it prior to release as a commercially-available product. The problem is that it can become an exclusive product, driving the cost higher than necessary and preventing widespread adoption of the product.

I recall that you already have many patents under your belt, so you are well aware of the issues. I'm just interested in making sure that your design isn't stolen and used -- or misused -- in ways that dishonor your intent.

[Steve M Smith]

While few will appreciate this, I managed to do this layout completely single sided

That's always a nice achievement.
 

and deciphered their creative use of the english language

So it was written in American?!!


Steve.

[John Roberts {JR}]

Have you explored the existing patents for similar devices, specifically for non-contact voltage testers? I'd hate for you to get into trouble for infringing on someone's patent. I realize that the design is entirely your own, but a patent holder with an independent but similar design could still claim infringement.

Actually mine does not use non-contact technology. You need to contact mine to provide the local 0V reference.

I researched in the technology field of electronic touch controls and didn't find anything even close to my approach. 

One of the lesser-realized purposes of a patent, rather than to prevent copycat works, is to prevent someone else from filing a patent on the same technology thereby preventing your own use of your design. Proving that your work is "prior art" in the face of a false patent claim is likely to be expensive and difficult when you don't already have a patent.

The patent system rewards inventors with exclusive use for a limited time in exchange for publishing the knowledge so everybody else can learn from the invention and build upon it. I feel pretty confident I could prove my prior art inexpensively. I haven't exactly kept this secret, while a few months back I stopped publishing design improvement details, that I learned the hard way.  There are some subtle design details that are not obvious even to those skilled in electronics IMO. 

If you really don't want to file for a patent, then it may be in your best interest to open-source the final design. That will help to establish the design as "prior art". Alternatively, you sell the design to a manufacturer and let them patent it prior to release as a commercially-available product. The problem is that it can become an exclusive product, driving the cost higher than necessary and preventing widespread adoption of the product.

Again I haven't kept this secret so arguably it already is public domain. The US patent law used to require filing a patent application within one year of publication. International patent law stipulates filing before publication. I think the US may have harmonized with international law. I would assign my invention to a partner if they are willing to invest the money to pursue, but I suspect the horse may already left the barn. FWIW the beta test units I shipped out are equivalent to publication, not to mention my many discussions on the WWW. 

I recall that you already have many patents under your belt, so you are well aware of the issues. I'm just interested in making sure that your design isn't stolen and used -- or misused -- in ways that dishonor your intent.

My invention being copied would not break my heart... I am not doing this for the money. I need to keep some trade secrets about the design details in order to make this desirable for a partner to invest their resources into. At a minimum they need a head start on competition. In my exploration of partnership discussions I supplied a scrubbed scheamtic, that was missing a few critical circuit details. 

As i get older and more experienced, just because it is a good idea does not guarantee that it will happen or be commercially successful. I have faith in my design but not much more.

JR

[Frank DeWitt]

As i get older and more experienced, just because it is a good idea does not guarantee that it will happen or be commercially successful. I have faith in my design but not much more.

JR

As a mechanical designer for hire I have learned that this is VERY true.
If you build a better mouse trap the world will ignore you.  You need a good idea AND marketing.

I completely understand you not doing anything with this without UL approval.  Years ago I came up with a much improved car seat for children.  It allowed mom to get the baby in and out of the car without straining her back.  When I thought of marketing it I thought Babies, Cars, No way.