Dolphins in my driveway, under the boat??

[BOAT]

So I was in 'boat' last night connecting a device net wire from the ray marine backbone to the garmin backbone and I had the power line from the garmin backbone disconnected and hooked up the chartplotter and there was a loud and very fast clicking sound that seemed to be coming from everywhere down deep in the very bottom bilges of the boat where there are NO wires, NO devices, NO NOTHING!

What in the hull can THAT be I thought?? It sounded just like there were dolphins under 'boat' talking to each other.

Thinking a shorted fuse was sparking I quickly shut down the battery switch. So there I am sitting in the dark wondering what the heck was that? I looked under boat, no dolphins.

So then I removed my new backbone wire that I just spent so much time getting done and put everything back the way it was and turned on the batteries and everything was quiet again but then sure enough after a little while the dolphins came back!!

I shut stuff down, turned off things, but the dolphin clicks got faster and faster and i was having a hard time figuring out where it was coming from but when i disconnected the chartplotter it stopped - so I did all those wires one at a time and it was the depth-sounder transducer wire that stopped the dolphin talking sound. My transducer never made a sound before - so I was perplexed - I twisted it off it's mount (it's mounted in a cup full of glycol) and the sound stopped, I held the transducer to my ear and I could just faintly make out the clicking sounds - it was so faint, but when attached the the hull the sounds were so loud like as if 'boat's hull was a guitar box!

Really strange.

So is the depth sounder broke?? (It's one of those dual frequency chirp doo-dads. ) not really my expertise.

[Wind Chime]

I'm no tech either, so I'm going to say - you left your ballast tank gate valve open and a family of chipmunks moved into your empty ballast tank ?? Just a thought

[BOAT]

I'm no tech either, so I'm going to say - you left your ballast tank gate valve open and a family of chipmunks moved into your empty ballast tank ?? Just a thought

Hmmm, I never thought to look for creatures inside the ballast tank - I suppose a very small dolphins could get in there or a crab with claws - maybe I better not look.

I'm just wondering if the depth-sounder is broke now? Does anyone else have a depth sounder that makes dolphin clicks or fast sparky sounds like the electric ignition on a gas stove??

[RobertB]

Do you have a Class C fire extinguisher nearby?

[grady]

Isn't that how depth sounders work? Sonar? I have heard mine click while on the trailer. It did not resonate through the hull. Maybe somthing has changed with the mounting.

[BOAT]

Isn't that how depth sounders work? Sonar? I have heard mine click while on the trailer. It did not resonate through the hull. Maybe somthing has changed with the mounting.

Yeah, I'm on the trailer right now - I never noticed any clicks before but most all the other times I have the chartplotter on I'm in the water, so maybe being on the trailer has something to do with it???

[Gazmn]

It was ur depth sounder. If it's not - which I doubt, it'll be dead sooner than later. You can always drop some bleach in the ballast to speed up the process

[BOAT]

Well, I guess I will need to go back into the water to find out - after I launch I will open the gate so whatever it is can get out - and then maybe it will stop.

[Wind Chime]

Well, I guess I will need to go back into the water to find out - after I launch I will open the gate so whatever it is can get out - and then maybe it will stop.

or ... while on the trailer in your driveway (as-is), open the transom ballast gate and run your garden hose through the ballast air-hole inside the boat. Flush out the ballast tank in reverse

[Highlander]

I'm no tech either, so I'm going to say - you left your ballast tank gate valve open and a family of chipmunks moved into your empty ballast tank ?? Just a thought

Hmmm, I never thought to look for creatures inside the ballast tank - I suppose a very small dolphins could get in there or a crab with claws - maybe I better not look.

I'm just wondering if the depth-sounder is broke now? Does anyone else have a depth sounder that makes dolphin clicks or fast sparky sounds like the electric ignition on a gas stove??

U been drinking that home made Scotch again haven,t U if u took ur ear plugs out yer think the clicking noise would go away , get quieter or louder , if it gets louder turn around & see if the Admiral is standing behind U beating ur head with a broom pole just sayin that's all

J

[BOAT]

I'm no tech either, so I'm going to say - you left your ballast tank gate valve open and a family of chipmunks moved into your empty ballast tank ?? Just a thought

Hmmm, I never thought to look for creatures inside the ballast tank - I suppose a very small dolphins could get in there or a crab with claws - maybe I better not look.

I'm just wondering if the depth-sounder is broke now? Does anyone else have a depth sounder that makes dolphin clicks or fast sparky sounds like the electric ignition on a gas stove??

U been drinking that home made Scotch again haven,t U if u took ur ear plugs out yer think the clicking noise would go away , get quieter or louder , if it gets louder turn around & see if the Admiral is standing behind U beating ur head with a broom pole just sayin that's all

J

She was and said Yer bum’s oot the windae. But it was no use - I'm still hearing the clicking.

[mastreb]

I think it's probably fine. You just got some weird acoustic effect from the sounder because you're boat's not in the water. Imagine the ballast tank is like the echo box for a speaker or the body of an acoustic guitar. You're probably hearing a harmonic of the sounder frequency that is sympathetic with something it's touching.

These sorts of things can be very bizarre. As an EW (electronic warfare technician) in the Navy, I remember going past the commercial pier (10) here in San Diego Bay on my ship, the USS England, watching out over the water (on sea & anchor detail). Me and the other EW's all looked at each other simultaneously when we suddenly "heard" the SPS-10 radar.

EWs are taught to listen to the synthetically reconstructed sound that radars would make if they transmitted in the acoustic band as sound (they don't, they transmit radio waves). Just as AM/FM radios carry information on their carrier frequency that translates directly into sound by removing the carrier and putting the remaining base-band signal into a speaker, so do radars make a characteristic pattern of pulses that can be interpreted as tones along with their sweep information. It's a very specific sound pattern that only EWs and CTs in the Navy would ever hear, and we're taught to recognize radars by sound alone because you can key on "threat emitters" far faster by sound than you can by intepretting a bunch of digital instrument readings that instrument that sound.

Anyway, we were standing >outside<, not listening to our radar receiver, when we all heard the unmistakably specific "sound" of our own ship's navigation radar, clear as day, outside. Other sailors asked us what that crazy sound was, and we told them but we were all incredulous. This would be like "hearing" an AM radio signal without a radio!

Turned out the radar was striking the corrugated tin metal siding of the dock warehouses, and it was powerful enough and close enough that the radar pulses were causing the tin siding to vibrate sympathetically with the radar emissions. Adding to that a low thermocline that ducted the acoustic sound right back to us, we had all the ingredients for this once (actually twice) in a life-time strange occurence.

The only other time I've heard the unmistakable sound of radar outside of my job is when my 900MHz cordless phone picked up a Navy ship's radar off-shore. I was on hold when the acoustic signature of an SPS-67 radar started chirping in my phone. I picked up my binoculars, looked out over the ocean and saw an Amphib sailing by, and smiled. Years of training to identify just a strange bit of interference on the phone.

Anyway, that's what's going on. I think your sounder is fine, and you may never hear it again. Depends greatly on the confluence of circumstances.

[BOAT]

Okay, it does go away when I remove the transducer from it's "cup" that is glued to the hull. When I grab it and take it out of the cup full of glycol water the sound stops but if i hold the transducer right up to my ear i can just barley hear the dolphins clicking - really weird.