I built something similar about 10 years ago, it worked okay....If you have a wife and/or kids that you enjoy spending time with you might be better off buying one of the new Humminbird units. They produce a good image. Or you might consider renting a commercial unit if you've got a reasonable search area.
No wife no kids, thanks for the info I will take a look. I am in California I don't know where I could rent one out here but I will start looking, it there a ball park figure on what they cost to rent.
If I am looking for a 7 foot bronze item in 5 feet of water buried under 3 feet of mud, hypothetically, what is the most economical method of detecting the item?
Ouch! A sidescan won't do you much good unless it's laying on the bottom. Bronze rules out a magnetometer. You might look into sub-bottom profiling or even use a pulse loop if you know the general area - the pulse loop being much cheaper.
I'd have to ditto what Darren said. A pulse loop metal detector would be the most economical. Since were obviously not talking about a bronze sewer pipe. Is there any other potential debris that would be nearby?
Sidescan ill not help you...sub bottom is difficult to use...pulse md is best
5 feet of sand is a long waydown...being an ME/EE I will ask the guys at the office about the possibility of building a useful tool for just such a task
I am looking for a shipwreck at the bottom of a lake. Most of the lake is flat which should make it easy to find, but the problem is that there is only about 6 inches of visibility in the lake. Further from the research I have done the ship is in a sand dune at the bottom of the lake.
Well my friend I can understand your plight!!!!!!!
I am going through ALMOST the same thing.
I suggest that you first do Side Scan Sonar search.
Then use a MAG and THEN do the MD thing.
I also suggest that you KEEP VERY GOOD RECORDS on everything you are doing. You will find this important in more ways than one.
Be thankfull that you are not dealing with Gators, Sharks, Crocs and a very very swift tide change AND the State of Florida.
Keep at it and good luck.
Peg Leg
Well my friend, I have been down that road! All I can say is your time would be more well spent working at a job to pay for one to buy! If you have a full time job and can't afford say the Humminbird 987 or New 997 at $1900, get a 2nd job to foot the bill!
I have wasted so many hours working on projects like this and unless you are a complete electronics genius and mechanical engineer, I would hate to see you go down the same road I did.
Don't get me wrong, its doable! I built Dan's side scan and it works, but the images are nothing compared to what you get from a real side scan or the Humminbird. I have also built a fluxgate mag successfully, but I spend more time fixing it than I have had it in the water.
If you feel like saving a little money compared to the Humminbird, there is a fella named Gary Burton who has built a nice unit and sells a semi-kit form where you can build the towfish and buy the depth finder separate. It works off a Lowrance depthfinder and the data can be recorded and played back on your computer. The only, only, only downside is it looks to just one side not both. The resolution seems to be great. I think his packages start around $600.
You also might want to check out the Geotech forum and see some of the projects there. Its a great resource if you are serious about building mag, sidescan, metal detectors, etc.