Bone knocker

[6666]

Been trying to help a deaf friend get back into detecting, does anybody remember a device called a bone knocker
I believe they were on early whites under water detectors and the knocker slipped under the wet suit
does anybody know what is inside this knocker and what its made from ? thanks

[Polymer]

If I'm not mistaken, I believe it was a relay going klack-klack-klack.

[Carl-NC]

Yes, the early White's diver models had them. I have a Goldmaster Amphibian with a diver hood and bone knocker. Never took one apart so I don't know what's inside, but I assume it's some kind of solenoid.

[6666]

Thanks for reply's

[Tinkerer]

Been trying to help a deaf friend get back into detecting, does anybody remember a device called a bone knocker
I believe they were on early whites under water detectors and the knocker slipped under the wet suit
does anybody know what is inside this knocker and what its made from ? thanks

Use a solenoid and set the lowest frequency about 10Hz. The highest frequency will be limited by the inertia of the solenoid. Any small solenoid will do. You also need to add a diode across the solenoid to catch the flyback of the solenoid.

[6666]

Use a solenoid and set the lowest frequency about 10Hz. The highest frequency will be limited by the inertia of the solenoid. Any small solenoid will do. You also need to add a diode across the solenoid to catch the flyback of the solenoid.

Thanks
T

[dbanner]

Maybe use something which wraps around the wrist area with Velcro strap. White's pi 1000 also have LED which I think flashes in tandem with the solenoid.(not sure)