Ask questions about projects relating to: aerodynamics or hydrodynamics, astronomy, chemistry, electricity, electronics, physics, or engineering.
Moderators: MelissaB, kgudger, Ray Trent, Moderators
I build the crystal radio and it doesn't work. I wrapped the coils on a glass bottle. One of the coils in the middle moved out of place when I was sanding and it wont go back in its spot. It sits loosely on top of other coils. Could this cause it not to work? I turned the bottle around and sanded a new strip. Will having 2 sanded strips cause it not to work?
- Posts: 8
- Joined: Mon Jan 23, 2012 9:43 am
- Occupation: Student 8th grade
- Project Question: I am doing a project on disinfecting water with UV light. The Tryptic soy agar plates listed are not available. What should I use instead?
- Project Due Date: March 16,2012
- Project Status: I am conducting my research
Powfam06 - I'm not sure what radio design you are building, but it sounds like you have a tightly wound coil around your coil form, and the sanded strip you refer to is to allow a contact wire or slider to move across the bared copper coils to tune the inductor. If you rewound the coil after it had been sanded a first time, it's very possible that there are opportunities for the coil to 'short out' as adjacent turns possibly come into contact with each other. To be safe, you might want to rewind the coil with new, copper magnet wire, fix it in place with some adhesive, a few lines of 'hot glue' or other means of securing it to the form, then lightly sanding a narrow strip for the slider. I may be assuming the wrong design here, but that's what it sounds like to me.
- Posts: 496
- Joined: Sat Oct 25, 2008 1:26 pm
- Occupation: Technology Consultant
- Project Question: n/a
- Project Due Date: n/a
- Project Status: Not applicable
Return to Grades 6-8: Physical Science
Who is online
Users browsing this forum: No registered users and 3 guests