Passive Radiator Antenna on PCB

[Czechmarty]

Good morning guys,
I'm looking for boardhouse that can make some passive radiator antenna prototypes that you can see on attached pictures. The fiberglass needs to be as thin as possible and if doable then cut out in the shape of the radiator (the big top circle). I also need some suggestions as what to use for environmental protection. These antennas will be in plastic covers (not water tight) so I need some protection from water immersion.

Any ideas, contacts, phone numbers are welcome.

Thanks!!

Best regards

Czechmarty

 

[AnthonyZ]

www.SparkFun.com They will have all the answers you need and also have a short run fab house.

 

[zpollock]

I have a contact that might be able to help. Check your PM.

 

[Czechmarty]

Thank you guys!
I'll check both.

 

[BraveSirRobbin]

I have used conformal coatings in the past with good success as far as the waterproofing goes.

 

[Czechmarty]

I have used conformal coatings in the past with good success as far as the waterproofing goes.

The question is which one and which method...
acrylic, polyurethane, silicone, epoxy,.....
spray, dispense, dip,....

 

[Spanky]

If you need absolute water tight even in emersion, I used to make scuba diving computers and poured silicon gel around the PCB. It is a flexible goo, but it provides absolute water tight protection. It is the same stuff that breast implants used to be made out of.

 

[BraveSirRobbin]

I have used conformal coatings in the past with good success as far as the waterproofing goes.

The question is which one and which method...
acrylic, polyurethane, silicone, epoxy,.....
spray, dispense, dip,....

It has been many, many years, but I remember acrylic being the best as far as being water proof. The only problem is if you anticipate ANY movement with the parts it could develop a nick and compromise the insulation.

The polymers provide a little more flexibility and offer a pretty good water tight seal, just not as good as the acrylic.

Again, this was a while ago...

If you need absolute water tight even in emersion, I used to make scuba diving computers and poured silicon gel around the PCB. It is a flexible goo, but it provides absolute water tight protection. It is the same stuff that breast implants used to be made out of.

You might want to watch out for his method as a large 'thickness' of silicon will change the dielectric constant around the antenna. It might not be a big deal, but, as I don't know the details of the calculations/frequency involved, may be worth mentioning.