Tuna Topper and Rockmite Packaging

The 12 year-old and I got a chance this last weekend to test out the Rockmite complete with Tuna Topper amplifier on a POTA activation. The results were outstanding! We were making a QSO per minute for most of the activation. Something we've never done before.

On top of that, the prototyped packaging of the combo of devices solved a few problems we've always had when we suspended the Rockmite from the antenna. Here's a look at the how the pair were packaged together:

The first, biggest advantage, is that we moved the BNC coax connector out of the equation. As you can see, it is now the input to the Tuna Topper. That means that it is not supporting the antenna. That means that there are no longer any torques on the BNC connector in the case. This fixes an issue that inspired so many washi tape fixes.

The second advantage is that there is now access to the power leads outside of the Rockmite. This frees us up to send power in on a different path than the Ethernet cable inspired by the original Flying Rockmite and the OpenHeadsetInterconnectStandard from N6MTS. This means that we can bring big chunky power wires, perhaps twisted around the Ethernet cable, up to the Tuna Topped Flying Rocmite, reducing voltage drop. I'm looking into using 8 D cells as opposed to 8 AA batteries.

The last advantage relates to the first: The RF output lines are no longer attached to a coaxial BNC connector under radial stress either. The two banana posts seen at the top of the radio case attach to the antenna wires, and are attached to nothing inside the radio case. We're not going to have any more broken RF output feed wires!

Next steps are going to be to look at putting the Rockmite and the Tuna Topper into the same can to make everything a bit cleaner and easier to use.

Comments

Cool Math Tricks: Deriving the Divergence, (Del or Nabla) into New (Cylindrical) Coordinate Systems

Now available as a Kindle ebook for 99 cents ! Get a spiffy ebook, and fund more physics The following is a pretty lengthy procedure, but converting the divergence, (nabla, del) operator between coordinate systems comes up pretty often. While there are tables for converting between common coordinate systems , there seem to be fewer explanations of the procedure for deriving the conversion, so here goes! What do we actually want? To convert the Cartesian nabla to the nabla for another coordinate system, say… cylindrical coordinates. What we’ll need: 1. The Cartesian Nabla: 2. A set of equations relating the Cartesian coordinates to cylindrical coordinates: 3. A set of equations relating the Cartesian basis vectors to the basis vectors of the new coordinate system: How to do it: Use the chain rule for differentiation to convert the derivatives with respect to the Cartesian variables to derivatives with respect to the cylindrical variables. The chain ...

The Alcubierre Warp Drive Tophat Function and Open Science with Sage

I transferred yesterday's Mathematica file with the Alcubierre warp drive[2] line element and space curvature calculations to the +Sage Mathematical Software System today, (the files been added to the public repository [3]). If you haven't used Sage before, it's a Python based software package that's similar in functionality to Mathematica. Oh, and it' free. I also worked a little more on understanding the theory, but frankly, I made far more progress with the software than the theory. What follows will be a little more of the Alcubierre theory, plus, a cool Sage interactive demo of one of the Alcubierre functions[1], as well as a bit about my first experience with using Sage. Theory The theory is fun, but it's moving slowly. Here's the chalk board from this morning's discussion Alcubierre setup the derivation using something called the 3+1 formalism which means we consider space to be flat, (in this case), slices that are labelled ...

The Valentine's Day Magnetic Monopole

There's an assymetry to the form of the two Maxwell's equations shown in picture 1. While the divergence of the electric field is proportional to the electric charge density at a given point, the divergence of the magnetic field is equal to zero. This is typically explained in the following way. While we know that electrons, the fundamental electric charge carriers exist, evidence seems to indicate that magnetic monopoles, the particles that would carry magnetic 'charge', either don't exist, or, the energies required to create them are so high that they are exceedingly rare. That doesn't stop us from looking for them though! Keeping with the theme of Fairbank[1] and his academic progeny over the semester break, today's post is about the discovery of a magnetic monopole candidate event by one of the Fairbank's graduate students, Blas Cabrera[2]. Cabrera was utilizing a loop type of magnetic monopole detector. Its operation is in...

Copasetic Flow

Search This Blog