A 6PDT push button for COMM1/COMM2 radio switching

switch stereo audio, mic, and signals
switch stereo audio, mic, and signals

Traditional aircraft used an audio panel in the avionics stack to handle multiple radios, audio sources, and intercom between the occupant headsets. This was logical when there were so many audio sources which needed to be monitored for different segments of flight – two radios, identifying VORs and NDBs, listening for the outer marker signal, etc.

With the growing availability of GPS for all segments of flight including precision landing, some aircraft have done away with an ADF and even NAV radios. My plane is one of these. There are pros/cons to this configuration but for a lot of domestic flying, it’s safe and complete.

Many newer radios incorporate the intercom and even have alert and auxiliary audio inputs. With all of he capabilities of these modern radios, most of the audio panel capabilities are redundant. The exception is supporting two radios.

Two radios are handy since one radio should always be setup to talk to the airport or to air traffic control. The second radio can handle things like checking weather at the departure or arrival airport. It can also be helpful when you know you will be changing frequencies multiple times in a short period – eg: weather, clearance, ground, tower, then departure control.

Having two radios doesn’t dictate an audio panel. Switching frequencies has become much easier with database integrated radios and EFIS/GPS connected radios. With these systems, a frequency change is often a press of a button.

This leaves the listening to weather and the “convenience cases” when you want to load up clearance and ground to a second radio. The “listen” to the second radio can be handled through an auxiliary input on the primary radio. Now we have only one case to solve – temporarily switching to the second radio.

In a side-by-side airplane, both occupants have access to the panel but in a tandem (or solo) only the pilot can reach the panel. Only the pilot really needs access to both radios. My airplane is a tandem and I fly 99% solo.

A pilot headset has a MIC, a push-to-transmit, mono or L/R headphones, and the ground wire. That’s 5 connections. A switch can handle toggling all 5 wires at once between two radios.

The sixth switch lets us listen to the second radio while connected to the first.

Below a video of the switch. The switch has both solder lugs and PCB pins. The pins can be cut off when using the solder lugs. The push button switch “latches” when pressed and releases when pressed again. It has a mechanical colored indicator that is visible when pressed to the “latched” position.

6PDT Push Button Switch

Stereo farming

soy beans starting to turn

soy beans starting to turn

tomato stakes

tomato stakes

Making a spherical ice "cube" for a unique cocktail presentation

Swanky scotch and whiskey bars spend a fare amount of time (and money) on atmosphere and presentation – how else can they charge $20 for a $4 drink ?!

The glass is only part of the presentation and it’s easy to replicate at home. The ice is another story.

The first task is to create clear ice. There are a number of methods described on the internet and the one that proved successful was directional freezing, detailed by Camper English. I just had to call him out for having such a cool name.

IMG_4674_tuned IMG_4686_tuned IMG_4684_tuned

Using an inexpensive cooler, fill it with nothing more than tap water (or filtered water if your tap water is funky). Put it in the freezer with the top removed or open. Wait about 48 hours. In this time it will freeze down about 4". Remove the cooler from the freezer and let it sit on the counter for about 10 minutes then invert it in your sink and slowly, the block will fall out. It will still have an unfrozen portion. Knock this off to leave you with a block of clear ice. If you want chunks, break off pieces as needed.

To get a sphere of ice, you want to start with a more manageable piece. I tried carefully breaking the block but it was very unreliable and wasteful.

I took six 1-liter bottles and cut off the top and bottom. I drop these into the cooler filled with water before it goes into the freezer. After 48 hours, I remove the cooler as before and let it sit. Then, I break the block apart to free the cylinders. Each piece is about 4" tall as before.

Note: the one pictured has a small amount of front on it because I had tossed it back in the freezer for later use. If you do this, let it sit out for about 10 minutes to temper, otherwise even the temperature of your hand will shock the ice and crack it.

From "cylinder to sphere" you have two options, you can shape it by hand or using a press. Both methods take advantage of thermodynamics.

Hand Method: There are two manual options – melting and chiseling. Here is the chisel method. I tried my hand at the melt method. Using a large stone or thick metal surface, slide the ice cylinder across its face/top. The surface – being at room temperature – melts the ice. It’s a lot like sanding a smooth curve onto the corner of a piece of wood. Turn the cylinder and melt the edges. Keep shifting the ice to round it more and more until you have a sphere.

Press Method: Shell out big bucks, find someone else to shell out big bucks, or try to score a crazy deal on eBay to get an Ice Ball Maker (aka Ice Press). Open the press and insert the cylinder of ice and rest the top back on the ice. The small amount of pressure is now what is doing the work – it’s the mass of aluminum. It starts at room temperature and has a high thermal mass. It melts the ice and its temperature drops. If the chunk of ice is not too big, the excess will melt away as the metal comes in contact with ice. The technique works for shapes other than a sphere. Below is an example video … from Macallan, of course.


I think it’s time for a Gin. Hendricks, perhaps ?

Simple DIY “remove before flight” covers

1.5 inch red ribbon
1.5 inch red ribbon

For safety reasons it a very good idea to have covers the the various tubes sticking out of an aircraft. It helps keep bugs and debris from clogging vital systems like the pitot tube and the fuel tank vents.

You can buy very clear cover-flags for $10 to $20. Or, you can make about a dozen for less than $4.

You need a sewing machine (or the patience to do a bunch of hand stitching) and you need a roll of 1.5″ or 2″ ribbon.

I cut pieces about 12″ long. I used a lighter to singe the fray ends. Next I folded the long way and stitched about 4-6″. That’s it. They fit perfect over the 1/4″ tubing. For a full sized pitot tube you cut two pieces of ribbon – one at 12″ and one at 6″ and stitch then face-to-face.

Size is relative for the iPhone 6 Plus

big phone in a big hand vs small hand
big phone in a big hand vs small hand

A friend posted a link to Monday’s “Live with Kelly and Michael” where they are talking about the iPhone 6 Plus.

The interesting visual from the segment is the size of the phone appears to change. With Michael Strahan the phone looks completely normal but with Kelly Ripa, the phone looks huge!

Think before you CSS

execution order of CSS affects usability
execution order of CSS affects usability

Modern websites are a rich combination of content, behavior, and style. The behavior has traditionally been implemented in JavaScript and the style has been achieved with CSS.

Ten years ago, browsers were simple and so were web pages. Developers didn’t have a lot of tools. Java in the browser was one solution JavaScript was another. Both had their usefulness, both had their issues. Most Java in the browser has gone the way of the Dodo Bird … thankfully.

JavaScript hasn’t been perfect. It’s biggest strength has also lead to it’s biggest challenge – it’s very easy to learn and use which has lead to it being used A LOT! This make websites heavy and slow, especially for those with slow internet connections such as DSL connections and mobile cellular internet.

Web developers – good web developers – understand not only what JavaScript can do but also HOW it it is handled by the browser. Their testing covers transmission, loading, and execution – not just functionality.

HTML5 and CSS3 are enabling more and more behavior without JavaScript. Modern browsers are really “web execution engines”. Look at the size (install and runtime footprint) of a modern browser and it’s clear it has been built to be a runtime system. They are capable of performing image manipulation from real time scaling and drop shadow to 3D transformations.

The shift from JavaScript to HTML5 and CSS3 for these capabilities brings with it the same developer concerns.

The image in this post is of a website which took approximately 30 seconds to render. It makes heavy use of CSS. As you can see, the developers didn’t consider what happens when their CSS loads slowly. The site is unusable – even confusing – until everything gets loaded and executed.

A good web experience requires a “progressing experience” – one where the user can get value very early and gets additional capability and options as more of the content is loaded. It’s bad design when the “content” is loaded but unusable because the “style” is slow. This type of experience suggests the developers and the owners believe “style over substance”. I doubt they want that to be their slogan.