Can't work my NASA depth sounder

[Bertolt55]

Hello Folks - I've inherited an old NASA depth sounder on my boat and can't work out for the life of me how to use it. I've looked online, but can't find any instructions. Video is here: IMG 0877
Any ideas?
Thanks!

 

[tillergirl]

You should get two yellow blips. the one of the left is the transducer (as at 0), the light on the right should be for the bottom (are you ashore at the moment? If so it won't read properly - doesn't like air). A is the scale 0 to 20 metres, B is 0 to 100m. The knobs above are for setting the alarm. I think the green light is the alarm setting.

 

[ChromeDome]

Just go here for the manual

Stingray Echo Sounder - Nasa Marine Instruments

 

[Bertolt55]

Thanks for the replies folks - the boat is moored in about 3m of water. Would you guess the unit is faulty as the top light is always red and reading under 1m, and the bottom is green but reading somewhere between 0 and 20?

 

[Refueler]

I lost my old Seafarer flasher Sounder ... which works same as the above Nasa Stingray ...... annoyed as I really liked it ! For all its quirks.

As far as I remember .... you set for expected depth range ... and then reduce gain till you just have 0 dot and then another yellow dot at the depth .... if you have a long yellow tail - then gain is too high ... turn it down till you just have a dot flashed each time LED comes round.
The RED as I seem to remember are the ALARM set points ... which you can adjust ....

OK ... if the boat is in 3m water ... do not forget that this unit - if I remember correctly - does not have transducer correction for how far below Waterline it is. The depth indicated is what is below transducer .....

 

[Bertolt55]

I lost my old Seafarer flasher Sounder ... which works same as the above Nasa Stingray ...... annoyed as I really liked it ! For all its quirks.

As far as I remember .... you set for expected depth range ... and then reduce gain till you just have 0 dot and then another yellow dot at the depth .... if you have a long yellow tail - then gain is too high ... turn it down till you just have a dot flashed each time LED comes round.
The RED as I seem to remember are the ALARM set points ... which you can adjust ....

OK ... if the boat is in 3m water ... do not forget that this unit - if I remember correctly - does not have transducer correction for how far below Waterline it is. The depth indicated is what is below transducer .....

Ah - right, things start to make sense - I'll give this a try. The manual doesn't even start trying to explain this! Many thanks.

 

[Refueler]

Any luck ??

 

[Bertolt55]

Won't be able to get to the boat for ten days or so, so I don't know yet. Will let you know as soon as I'm home. Thanks again for the info.