Wednesday, February 25, 2015

Stick this thing in your ear to lose weight

Say hello to the BitBite, a wearable health coach that you stick in your ear to help you improve your eating habits. Oh, and it's a fully functional Bluetooth headset too.

Today's entrant in the world of weird wearables is BitBite, a new device that monitors how much you eat, as well as the type of food you consume. Did we mention that you stick it in your ear?

BitBite has a small, contoured design that its creators claim is built to perfectly fit your ear for maximum comfort. To use BitBite, just put the patent-pending earpiece in your ear at mealtime, and the gadget will, using a built-in microphone and sensors, automatically track how quickly or slowly you chew your food and how much food you're taking in. It then sends that information via Bluetooth to an app that analyzes the data.

You can even talk to BitBite, via the mic, to tell it what you're eating (no lying now!), which further lets the product assess your habits and coach you in real time to do better.

For example, BitBite can tell you to PUT THE DOUGHUT DOWN, DUDE and opt for a piece of fruit instead, and it can remind you to slow your chewing down so you become more mindful of your body's cues and stop eating when you're feeling full.

All this information is managed with a connected app for iOS and Android devices. From what we've seen of the app so far, it seems well designed and presents users with a ton of information -- from the amount of bites taken to the amount of protein, carbs and fat ingested.

In addition to being able to track your eating habits, BitBite also functions as a Bluetooth headset, though its battery life -- three hours on a single charge -- will probably have you reaching for the charger often if you plan to use BitBite as a Bluetooth earpiece. The company says the battery life is good enough for three days of monitoring your food intake, however.

BitBite has launched a crowdfunding campaign on Indiegogo to help bring its product to market, and has raised $27,813 of its $60,000 goal as of this writing. The current price for one BitBite unit for early backers is $109 (about £69.39, AU$125.02), and that will jump to $119 (about £75.75, AU$136.51) once the 200 earlybird units have been reserved. Each unit comes with a USB charger and a wristband or clip so you don't lose the BitBite while it's not in use, and shipments are expected to begin in June 2015.

BitBite looks to be a compelling product that could help users adopt healthier habits, but you will have to deal with the fact that you're going to be that person walking around with a weird thing in your ear to help you get there.

Thursday, February 19, 2015

How Many 2 way radios Can Run on one Channel?

Theoretically, you can use an unlimited amount of walkie-talkies on the same channel (although in practice you might experience a few problems if you took that suggestion literally). Basically, there isn'€™t really a set limit. You could use as many as you like provided they are set up correctly. Anybody set to the right channel and in range at the time of transmission would then be able to pick up the signal and respond to it.

Most radios have access to 8 channels. These channels each have 38 separate €˜identification tones€™. The user sets his/her channel up with the desired tone and then only other users who know the channel/tone will be able to hear the transmissions. As a result, there are, in any given area, about 304 different combinations, so signal interference is unlikely to affect you.

Please do not interpret this answer as saying that your radio has access to 304 possible channels. It does not. It will likely only have access to 8. Some less reputable manufacturers tend to falsely imply access to 304 channels; this is simply not the case. You will have access to 304 possible tone/channel combinations, thata€™s all.

To better explain the CTCSS codes and how they work; we'€™ll include a little information from€™s FAQ page.

€œCTCSS stands for “Continuous Tone Coded Squelch System”. These codes are also often called “Privacy codes” If a CTCSS tone is selected; a CTCSS sub-audible tone is transmitted along with the regular voice audio by the transmitting radio. The receiving radio, set to the same CTCSS tone, will only receive audio if it contains that sub-tone. Interference from other users on the same frequency is therefore rejected (unless they are also on the same sub-tone). This is a way of allowing groups of users of walkie-talkies on the same channel to avoid hearing messages from other nearby usersa€.

So, in conclusion, you can probably use as many walkie-talkies as you like on the same channel. As long as the units in question are of the same type (either VHF or UHF) and have the same CTCSS setup, then you simply shouldn'€™t have a problem. You also shouldn'€™t suffer from signal interference due to other users (although you may still experience signal loss/interference/degradation from other sources). We have talked about combating signal loss elsewhere, so please see the other questions if you have any problems in this area.


Thursday, February 12, 2015

What is an Acoustic Transducer?

From “What is an Acoustic Transducer?” (12 January 2012)

An acoustic transducer is an electrical device that coverts sound wave vibrations into mechanical or electrical energy. They have various practical applications, including sound recording and sound playback. A specialized model, called an ultrasonic acoustic transducer, can be used to measure distance to, as well as the mass of, an object.

Common types of acoustic transducers used in sound recording include microphones, earphones, and guitar pickups. These create electrical energy when moving parts inside the transducer, such as electrical plates or ribbons, are exposed to sound vibrations. The electrical energy produced inside the transducer is sent first to an amplifier.

The amplifier then sends this energy to its final destination, usually a loudspeaker or recording device. The loudspeaker reproduces the sound at a level that the human ear can hear. A recording device will retain the electrical signal information. The recorder will send the stored signal to a loudspeaker during playback.

An ultrasonic acoustic transducer can be used to measure distance or the mass of an object. The most common type is the piezoelectric acoustic transducer. These include a piezoelectric ceramic element that creates and distributes ultrasonic sound waves.

Sound waves travel to an object from a piezoelectric transducer through material called a couplant. The couplant is usually water. Sound waves bounce off the object and return to the transducer in the form of an echo. The time it takes for these echoes to return to the transducer is used to calculate the distance to the object.

Underwater sound navigation and ranging (SONAR) is a common use of an ultrasonic acoustic transducer. SONAR uses directional beams of sound waves. This enables the SONAR operator to determine the direction and distance to an object.

SONAR systems can be active or passive. An active system sends out sound waves and listens for echoes. A passive system listens for noises made by ships, fish, and landmasses.

An electromagnetic acoustic transducer (EMAT) is another form of ultrasonic transducer. Instead of a ceramic element, an electro magnet is the main component of an EMAT. This is a type of non-contact, or non-destructive transducer. Unlike piezoelectric transducers, EMATs do not need a couplant to carry sound waves. Instead, two electromagnetic fields are generated to disburse ultrasonic waves.

EMATs can easily be used almost anywhere since no liquid is needed. For example, EMATs can be used to check for flaws in underground pipes. A downside to EMATs, compared to piezoelectric transducers, is that EMATs create weaker sound fields.