Project TouCans Slims Down to a Single Power Supply

Up until yesterday, Project TouCans required two battery packs, one in the rig itself to power the Rockmite and Tuna Topper amplifier and a much smaller external one to power the Pico-W that controls the rig's keyer and straight key. I tried bringing a USB A cable directly from the Imuto power bank in the rig out to the Pico-W, but the RFI was too much for the Pico-W causing it to reboot, or just turn off. That led to the two or three AA battery battery pack, which frankly was a bit to much extra weight, and a bit unwieldy.

Thant's all fixed now! I added as second Adafruit USB-C power adapter to the rig and that provided enough filtering that the Pico-W is happy as long as I make sure the rig doesn't transmit at all until the antenna is completely unfurled, which is a pretty reasonable expectation. When/if the rig does transmit with the antenna bundled up, the Pico-W reboots, then it presses the straight key which upsets the rig, causing the rig to reboot, except on reboot, the rig's keyer no longer functions. This is actually a nice failure mode as it breaks what could be an infinite loop otherwise. The rig's USB-C adapter is partially obscured by the USB-C cable that is attached for charging. The Pico-W USB-C adapter can be seen on the right.

Part of the rebuild was facillitated by 3M double sticky foam tape. It made for a simple installation of the Pico-W onto the relays and the relays onto the side of the can.

Detailed picture of the Pico-W mentioned in a previous post. Note that it's legs up and has it's relay and power wires twitsted together and nested between the legs.

Last night, on the initial test of the newly configured rig, I had a QSO with KF6VB across the Bay in Hayward. Our signals were ground-wave, and therefore a bit weak, but the QSO was clear! I left the rig on over night from 03:50 UTC. at 11:20 UTC the rig made a QSO with WX7V in Texas! The power pack lasted over night even with the added load of the Pico-W!

Finally, at about 16:30 UTC this morning, the buck converter in the Imuto power brick finally started to hum indicating it had turned on its switching power supply. I took the rig down to recharge which is what you see it doing above. The USB cable that brings power out of the rig also brings the charging current in.

The new battery arrangement led to no dropped Wi-Fi signals as well. I suspect this is because of a more solid current source at from the Imuto USB-C power brick. Here's the Chromebooks' signal report.

One last thing of note. While the hum was annoying enough for me to bring the rig into dry dock for a charge, the transmit signal was still S9 at the Utah SDR with a noise floor over there between S1 and S2.

S-meter of Utah SDR showing noise floor reading of S1 — Noise floor at Utah SDR this morning

S-meter of Utah SDR showing Project TouCans received at S9 — Project TouCans calling CQ at S9

Here's a rare (the only?) video of Project TouCans looking back up at the home QTH. Note the hill between most of the dipole and the Pacific about 3 miles away. (Yet, TouCans is reguglarly spotted in Hawaii and occasionally in New Zealand. And has a QSO out to Hawaii under its belt.)

More Cowbell! Record Production using Google Forms and Charts

First, the what : This article shows how to embed a new Google Form into any web page. To demonstrate ths, a chart and form that allow blog readers to control the recording levels of each instrument in Blue Oyster Cult's "(Don't Fear) The Reaper" is used. HTML code from the Google version of the form included on this page is shown and the parts that need to be modified are highlighted. Next, the why : Google recently released an e-mail form feature that allows users of Google Documents to create an e-mail a form that automatically places each user's input into an associated spreadsheet. As it turns out, with a little bit of work, the forms that are created by Google Docs can be embedded into any web page. Now, The Goods: Click on the instrument you want turned up, click the submit button and then refresh the page. Through the magic of Google Forms as soon as you click on submit and refresh this web page, the data chart will update immediately. Turn up the:

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 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 concept very sim

Copasetic Flow

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