Rotator controller causing condensation / water!

[Moleculo]

The strangest problem has started occurring in the shack - the inexpensive RCA antenna rotator controller is causing water to form and puddle up underneath of it on my desk! There is no evidence of roof leaks; if it where coming from the roof there would be splashes. The water is not coming in on the cables because that comes up from the floor. Over the course of a couple days, a good size puddle of water appears below the controller and it seems that it is coming from the device causing enough condensation to puddle up. Could this be an electrolytic capacitor or something else causing this? Could it be triggered by HF RFI coming in on the cables? The weirdest part is that the controller has been turned off for several days but still water appears!

Has anyone heard or seen anything like this?

 

[sp5it]

Water inside cable. Capillary effect.

 

[Dr. Frankenstein]

Mouse pee.........

 

[Tom Line]

FM - Reminds me of the dog that only barked right before the phone would ring.

 

[groundwire]

only a few things could cause this really. you have eliminated most of them. i would check for heating on the inside of the controller causing condensation (although very highly unlikely). next possible guess and probably the cause is water in the cable coming out due to capillary effect as sp5it mentioned. disconnect the cable from controller and put it on the desk, watch if it weeps water. a key piece of the puzzle which you didn't mention is the weather outside when this phenomena occurs. only when it rains, after it rains, sunny all day every day, snow, ice, etc. one last thing, if you have the cable length to spare, cut a few inches off and check the wires for corrosion. that will also help solve the mystery.

 

[Tom Line]

When outdoor cables are exposed to changes in temperature they expand and contract. This causes them to suck and expel moisture from ends and cracks depending on the temperature changes. Foam insulation in a cable should stop this kind of thing if that's what you have. Therefore I suspect the dog. Not having a drip loop at the point where the cable enters the house may be suspect as well. ( there isn't a sweating cold water pipe over your rig is there).

 

[nomadradio]

Water inside cable. Capillary effect.

Makes it run uphill, at least for a few feet.

73

 

[SuperLid]

The strangest problem has started occurring in the shack - the inexpensive RCA antenna rotator controller is causing water to form and puddle up underneath of it on my desk! There is no evidence of roof leaks; if it where coming from the roof there would be splashes. The water is not coming in on the cables because that comes up from the floor. Over the course of a couple days, a good size puddle of water appears below the controller and it seems that it is coming from the device causing enough condensation to puddle up. Could this be an electrolytic capacitor or something else causing this? Could it be triggered by HF RFI coming in on the cables? The weirdest part is that the controller has been turned off for several days but still water appears!

Has anyone heard or seen anything like this?

 

[SuperLid]

I have seen it many times. Water is getting into the cable at the rotor and migrating to the controller by capillary action.

 

[nomadradio]

The tiny spaces between the strands of coax shield braid will do this as well. This amplifier has oxidation and precipitated solids from rain water that seeped down the coax for some extended period of time.

Now and again a customer would report a mysterious tiny puddle of water on the desk where the antenna coax plugs into his wattmeter. I tell him the bad news is he probably needs new coax. And a better job of waterproofing the antenna end of the cable.

73

 

[Moleculo]

The cable for the controller is just a multi-wire cable with no foam. There is a drip loop and it does run back up a few feet to my desk. There has been more rain in Southern California this season than we have seen in 30 years...the capillary explanation has to be it.

 

[Chevboy0167]

OK.... now we need a time lapse video of such offense! LOL