Correction: a variable capacitor that would tune this to the AM band would be in the range of 12 pF to 120 pF, not 100 to 200 pF as stated. This is the series on how it was created: Crystal Radio Variometer-Commutator Questions & Comments (4K) ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-1gWW37SIFp0.html Crystal Radio Variometer Pt6.2 - Closure (4K) ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-z-4MAjnB4mw.html Crystal Radio Variometer Pt6.1-- New Beta Version Works! ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-xVQVQnKYP0A.html Crystal Radio Variometer Pt 6 - Protoype Is Done! Will It Work?!?! ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9PO__GsDkAg.html Crystal Radio Variometer Pt5 - Ball Is Done! ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-DCI8sSCJbQc.html Crystal Radio Variometer Pt4 - Better Yet! ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Nzp4hJsnCSU.html Crystal Radio Variometer Pt3 - Design Improvements ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-ooQ8eOIXAaM.html Crystal Radio Variometer Pt2 - Winding The Ball ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-T25Eq2C1iSk.html Crystal Radio Variometer Pt1 ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-RgJen7UGZ4M.html I have the updated 3D printers files posted on line here: www.thingiverse.com/thing:6290893 www.printables.com/model/632114-crystal-radio-variometer-aka-vario-coupler
Kevin Louhin also had some issues on his variometer wiring. There is a couple schematics on his video called Get on 630 meters with bucket variometer! He speaks about them after 13:50 point of the video.
Have you made any change to the 3D files or it is as in last video. It looks great and I will try to build one to. Thanks for the entertainment. Has been interesting to follow how it evolved.
The latest ones are on Thingiverse and Prusa. There have been lots of changes, so you will probably want to download them again to ensure you don't have old ones. You might want to print them in a higher melting temp plastic. PLA is OK, but next time I'm going for something else.
I have not tried it yet, so I can't say for sure. It's a close copy of an antique one, so there is a good chance it will work as well as any. You might need to vary the wire tye and size for your application.