This was in June 2023 and they finally cut the dish mounts off at ground level 3 or 4 years ago.

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My CCW dual polarity H/V antenna, has never had condensation.

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Chris used a Hammond RP1060 with a

Hylec vent and wire glands of unknown manufacture. There is no obvious name on the exterior. [I'm looking at it right now, not quite willing to tear it apart until my new Hammond cases arrive.]

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The RP1060 has a tongue and grove case with a neoprene gasket.

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The Hylec vent has a special membrane,

Polyether sulphone PES, similar to Gortex in that it allows air to freely pass but blocks water. I suspect it has much smaller holes in the material and is even better at blocking water then Gortex.

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I received this antenna at least 3 years ago, maybe 4 or 5 and it was placed in service that weekend and endured a series of storms.

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I opened it after the storms passed, no trace of water, I then installed it "permanently. [I used "" because it's been moved 3 times]

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I opened the case after the first winter, in late March and there was no trace of water.

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Central Kentucky gets a lot more rain in winter then snow.?Here is a list of average monthly temperatures and precipitation

https://www.usclimatedata.com/climate/lexington/kentucky/united-states/usky1079

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As you can see, we receive ~45 inches of precipitation, most of that is in the form of rain.

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I neglected to open the unit for the next few years. I opened it prior to moving last year, August, and then again this spring, March.

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There has never been a trace of condensation.

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As I explained in the post that started this thread, my theory on moisture ingress suggests water doesn't seep in along well sealed seams but is sucked in as air laden with water vapor as the temperature drops and the volume of air inside the case decreases, the water vapor condenses and is trapped.

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[I'll admit I haven't used Charles' and Boyle's Law since university physics...so please bear with me,]

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https://chem.libretexts.org/Courses/University_of_California_Davis/UCD_Chem_002A/UCD_Chem_2A/Text/Unit_III%3A_Physical_Properties_of_Gases/06.03_Relationships_among_Pressure_Temperature_Volume_and_Amount#:~:text=Because%20PV%20is%20a%20constant,equation%20V%20%3D%20constant%2FP.

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V∝T [anyone up to calulus?]

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https://www.omnicalculator.com/physics/charles-law

"In the second problem, we heat an easily-stretched container. It's filled with nitrogen, which is a good approximation of an ideal gas. We can find that its initial volume is?0.03 ft??at room temperature,?295 K. Then we put it close to the heating source and leave it for a while. After a few minutes, its volume has increased to?0.062 ft?. With all of this data, can we estimate the temperature of our heater?"

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Let's reverse this, if the temperature is decreased, the volume of air will decrease from 0.062 ft? to 0.03ft?. [Air is mostly nitrogen and I don't feel like trying to calculate precise thermal expansion/contraction versus temperature for the mixture of gasses that compress out atmosphere.]

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Here is a practical example. Take an empty 2 liter sodapop bottle at room temperature.?Screw the top on tightly. Place in your refrigerator.

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Leave for an hour and then remove, notice how the sides have pulled in? The volume of air in the container has decreased as the result of cooling.

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In the world of electronic enclosures in the real world, do you think the decrease in air volume might not suck in air laden with moisture? And might not an alternative air vent that allows air and water vapor to move both ways might prevent air laden with moisture from condensing because it can escape just like if there were vent holes?

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I am not trying to argue, I will state as a fact the CCW dual polarity antenna with the Hammond case, wire glands, and Hylec vent doesn't have any water condensation after a typical year in central Kentucky. Or after several years in Central Kentucky.

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Also, a Carlon PVC case with a tongue and grove mating surface and the factory supplied flexible gasket (I believe it is neoprene, but I'm not sure), a wire gland and a quarter inch hole with Gortex repair tape on both sides has also never had condensation after a typical central Kentucky winter. This case protects a PA0RDT Mini-Whip antenna.

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I've been playing with active antennas since July 1979. Most were E-Field antennas. All of them experienced "water ingress" [Well except for the vacuum tube unit, it was warm to the touch at 10F and over heated in 50F weather] until the CCW.

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Based on my experience with that antenna I decided to try the Gortex tape for a friend who needed an antenna "now." It was late September, a series of t-storms was forecast the next day and I had a contract job which promised to be a nightmare for the next few months. The Hytec vent has a delay (really long delay) getting here from England, so I took a gamble with the Gortex repair tape. I was out of my preferred spray on conformal silicon coating, so the PCB went in 'naked.' I threw the whole thing together in few hours and half expected it to maybe last the winter but would probably need the PCB replaced come spring. That was 3 years ago.

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https://www.hylec-apl.com/datasheet/1047/JDAE12PA_SW-Datasheet.pdf

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Until proven otherwise, I'm sticking with my "lower air temperature means less air pressure, means sucking in air/moisture from the outside and trapping the moisture inside after it condenses."

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Now I'll agree if you do not properly seal any ports, you will have water "wick" in by capillary action.

https://en.wikipedia.org/wiki/Capillary_action

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Look up Capillary action on youtube. There were too many demonstrations for me to pick out the best one. Water will be "sucked in" narrow gaps, the narrower, the further the water will be 'sucked in' regardless of temperature.

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This is capillary action and demonstrates how any unsealed opening can allow water in regardless of air temperature, pressure differential, etc.

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One must properly seal all ports. I use wire glands with "O" rings on the base of the wire gland that mates with the case.

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I've used conformal silicon coating to protect, seal, the seams on PVC cases that don't have tongue and grove / flexible gaskets with the 1/4 hole with Gortex repair tape.

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I have a Geiger counter mounted in aluminum Budd case. [I only want to detect Gamma rays <cosmic rays for a random number project for a cousin of my wife>]. Given the unit operates with 400V, any water condensation would be "a really bad thing." The unit has a ~9V to 400V inverter, is powered via the coax, the clicks are amplified and fed back down the same coax with a Bias-T.

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The coax enters via a wire gland with "O" ring, and I sealed the seams with spray silicon conformal coating. The breathing vent is a Hylec vent.

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This unit has been in constant 7/365 operation for 15 months with no problems. Unless I open the unit, I can't be certain there hasn't been any water ingress, but, given the inverter board is mounted on two strips of double sided tape [non conductive PVC] on the bottom of the case, I have every reason to believe there has been no water ingress. And any condensation on the GM tube would stop detection.

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I accept holes in the bottom were the only way to control condensation in the past, I also accept that modern vents allow us to have better moisture control and keep insects out.

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Our hobby is fun but industry depends on reliable equipment, condensation would be a major problem for them. Somehow I can't see a major telecom outfit relying on a couple of holes to control condensation.

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I suspect Don Clement's use of Qingrong "Blue Breather Plug M12x1.5-10 Venting Screw In Vents for Solar GPS Tracker Box, Outdoor Lighting Prevent Condensation,5G Outdoor Telecom Enclosure" will work every bit as good as the more expensive (and damn near unobtainable) Hylec or Honeywell.

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The secret is in the membrane that allows air to pass but stops water. I suspect Honeywell and Qingrong [and many others] have developed/copied the membrane used by Hylec.

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Given the 'really bad stuff happening if there is water condensation in a high voltage PV array / control' I suspect Qingrong's products almost certainly work as advertised.

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I've ordered several and I'll see how they work. I'm still going to stick to the Hylec for critical applications until I get a better feel for the Honeywell and Qingrong.

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The stick on water barriers mentioned by Fred M. appear to be a bit more professional then my Gortex tape.

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Just remember if you want to be a pro in PCB design stick and learn imperial if you are a metric country.? Thats design rule 1!

Honeywell makes one that might be as good, I'll let you know in a year or so.

https://www.digikey.com/en/products/detail/amphenol-ltw/VENT-PS1NBK-N8001/7898283

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Some thoughts on cases for exterior loop antenna amplifiers. This equally applies to any electronics in exterior service.

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The top of the line cases are polycarbonate, Hammond probably manufactures the best as a mix of price, function, availability. Durable like they are designed for combat.

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Look up "Hammond Water-Tight ABS & Polycarbonate Enclosures"

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I've never been able to locate polycarbonate wire glands but black Nylon is probably as durable and UV resistant and readily available on Amazon.

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For controlled ventilation, the "Hylec vent" is probably the gold standard. This vent allows air flow but blocks humidity. This is what Cross Country Wireless used in my dual polarity horizontal and vertical active dipole. Sadly they come from England and have insanely long delivery times.

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Honeywell makes one that might be as good, I'll let you know in a year or so.

https://www.digikey.com/en/products/detail/amphenol-ltw/VENT-PS1NBK-N8001/7898283

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I built a PA0RDT mini-whip for a friend on a tight budget. I drilled a 1/4" hole in the bottom and used Gortex repair tape on the inside and outside. It's been in service for 2 years now and given we've had temperatures ranging from 98F to -10F, over a foot of water, 2 feet of snow (spread out over 2 winters), I suspect the crude Gortext double seal works just fine. However I still do not trust it for anything serious. Given how inexpensive the Honeywell vents are, I'll spring for one and replace the Gortex.

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Hammond polycarbonate cases are the ultimate and priced accordingly.

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PVC cases are much more affordable.

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I use Carlon electrical utility boxes for less serious projects. These feature a neoprene gasket that provides a reasonably good seal and stainless steel screws.

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I've found Carlon cases to be suitable for many exterior projects and for cases for interior projects. The walls are reasonably thick, the cases reasonably strong, and, the price several years ago was very reasonable

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[I ended up with oodles when an electrician friend hung up his tools.]?

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A catalog is available at

https://carlonsales.com/electrical.php

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Lowe's used to carry these but appear to have shifted to Cantex. Cantex is similar but uses zinc plated screws, which are guarantied to rust here in Kentucky. I have no experience with the quality of the weather seal in the Contex units.

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The Carlon utility box is just starting to show some wear from the weather.

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Our POTS (Plain Old Telephone System) landline NID/DSL filter is in a PVC box. It's sheltered from direct sunlight being on the north side of our home. The phone company supplied the box and internal frame and NID, I added a DSL filter and Cat 5 wiring in the fading dream Windscream, er sorry, Windstream will extend DSL out to where we are and I can give up a Consumer Cellular phone based WiFi hotspot.

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Oddly enough the local electrical inspector approved Cat 5 wiring from the Windstream NID to inside our home with no comments about "You need transient protectors." I guess the Tii belcore lightning transient in the NID qualifies.

https://tiitech.com/wp-content/uploads/datasheets/surge-arresters/356.pdf

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They meet UL 497 and Telcordia GR-1361 Core protection requirements.

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They also installed a NID case more suited to an 8 dwelling apartment building, too bad I can't legally do anything with the spare space. The installation tech allowed me to install the DSL filter. Nice of her.

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The GTE PVC box at my parents home was at least 40 years old when we sold the home and still in good shape and it was on the south east side of the house and received hours of direct sunlight.

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So PVC might be OK for extended service.

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I'll continue to use PVC for casual projects but for my CCW dual polarity H/V antenna and my N4CY loop amps, I'll go with the Hammon polycarbonate cases even though the PVC cases I've used for the N4CY looks have held up nicely.

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OK a bit of theory here. I suspect we have water ingress because the changing temperature, cooler, sucks in moisture laden air, by having a vent that allows air but blocks all humidity, we don't get condensation. A life time ago when I went for long hikes in the rain, a standard vinyl raincoat made you feel like vegetables getting steamed, I was amazed at my first Gortex raincoat, no steaming of the hiker. I've often wondered of an experiment to verify this theory. I sort of accept the Gortex tape as sort of proof.

YMMV

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