Do fish finders lie?

[JBledsoe]

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We were fishing on a lake yesterday, water temperature was about 52 degrees, water clarity was about 6 feet. Sonar (fish finder) is a Lowrance 135c and the digital read out indicated 15 ft. water depth, same as the screen display. The screen display showed a level bottom (we were not moving) that looked like soft mud. When I dropped anchor it went down 49 feet!! Then I dropped a weighted line, same thing, 49 FEET! Yet the sonar was showing only 15 feet.

Anyone have an answer? ....thermocline?, zoo plankton?, Loch Ness?

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[jaxsprat]

Question: Do fish finders lie?

Answer: Not as much as Fishermen do............:rolleyes::D

[lhumphre]

was it on simulate mode?

[dedawg1149]

no they dont lie ,but we as fisherman seem to read them wrong

[JBledsoe]

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Thanks, you guys are a lot of help.

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["G"]

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We were fishing on a lake yesterday, water temperature was about 52 degrees, water clarity was about 6 feet. Sonar (fish finder) is a Lowrance 135c and the digital read out indicated 15 ft. water depth, same as the screen display. The screen display showed a level bottom (we were not moving) that looked like soft mud. When I dropped anchor it went down 49 feet!! Then I dropped a weighted line, same thing, 49 FEET! Yet the sonar was showing only 15 feet.

Anyone have an answer? ....thermocline?, zoo plankton?, Loch Ness?

.

Mine will sometimes read crazy like that....In my case its is usually scum or algae slime or something on the bottom of the transducer.....wiping off the transducer will get mine back reading right.

[skeetbum]

did you turn it off and back on? Mine gave a funky reading last week and after that(turn off and on) it was business as usual. Only other thing I can think of might be a bad component. If it's a bird, go to the electronics and TM forum and ask Greg about it. He's pretty sharp.

[Fishtaco]

Did you perhaps have the thing set up to read in meters instead of feet?

Fifteen meters is equal to 49.212 feet.

[blairarnold]

Question: Do fish finders lie?

Answer: Not as much as Fishermen do............:rolleyes::D

Oh, man, you beat me to the punch.

[fishinRod]

sounds like Fishtaco has the answer