Extreme Weatherproofing for NeoGeo Watch

[krazy]

Hi all,

I'm building a NeoGeo Watch that I'd like to bring to Burning Man.

Burning Man occurs in the desert, in extreme temperatures, wind, and dust, and I'd like to bring my NeoGeo Watch there.

I was wondering if anyone had any suggestions on how I could weatherproof the NeoGeo Watch?

I was considering potting using epoxy, but am concerned about how it would affect the electronics (i.e. GPS reception, etc)?

Any ideas?

Thanks!

[Franklin97355]

Conformal coating would probably be enough to get you through Burning Man.http://en.wikipedia.org/wiki/Conformal_coating

[Barry914]

I found plastic boxes at the Container Store that were almost a perfect fit for the stack of boards that make up the watch. The GPS sensitivity was very poor because the acrylic was in direct contact with the GPS patch antenna. I cut a square the size of the antenna in the box cover and used E6000 to glue a thin piece of glass over the hole. I used a piece of microscope slide for the glass. I stacked two of these back to back and put a 500 mAh Lipo battery and a charger in the 2nd box. The only thing it would need to be weather resistant is some tape around the box cover seams and some tape to cover the holes I cut for the USB ports for charging and data. It's not exactly wearable, but it could be if you don't use the 2nd box, you attach the strap to the box and use the band to hold the battery as in the original design.

[krazy]

Nice!! Thank you so much for the info, Barry!!

So your experience was that even a small piece of acrylic detuned the GPS antenna?

I'm thinking that means acylic potting is out...

[Barry914]

Yes, almost any material in direct contact with the antenna detuned it enough to make the GPS unable to get a fix. Glass was less of a problem than the plastics I tried, but it still caused a loss of sensitivity when in contact with the antenna. A gap of a couple of mm between the glass and the antenna was enough to restore normal sensitivity.

[krazy]

Do you know how acceptable the GPS performance would be, if it were under acrylic, but had a few mm of space?

Ultimately, I want to put this in a plastic box w/ a watchface, and create an aesthetic timepiece from it. So I'm leaning towards covering it up, however possible, if possible.

[Barry914]

No, I don't have any real data on how various materials affect the GPS sensitivity, but I used acquisition time as a proxy for signal strength when I was looking to package my watch. I just tried various materials both touching the antenna and with a small gap (about the thickness of the acrylic box I was using) and noted how long it took to acquire a fix. You could do the same I suppose.