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Receiver Noise Bridge – Pt 2

 

Receiver Noise Bridge – Pt 2

Filed in homebrew on Jun.04, 2010

I found some 1/2″ aluminum angle stock that I used for the mounting bracket.  I first tried to rivet it to the box, but the box’s shell was too thin, and the rivet wouldn’t pull tight enough, so I ended up using nuts and bolts (#6).


So with the angle stock secured to the sides of the watch case, I just had to mark, drill & tap the top holes to hold the circuit board in place.  I used a #36 drill bit and a #6 tap for the mounting holes.


So here the circuit board is attached to the watch case.


So next, I started on the capacitor.  Most of the designs used about 250pf maximum capacitance.  More capacitance makes the tuning more critical.  So I removed some of the plates by careful use of small pliers. After removing 5 plates, I ended up with about 255 pf of capacitance, with about 10pf on the bottom end.


 

Continued Part 3…

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