Altimeter Beep Counter

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cwbullet

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Has anyone ever thought about making a counter for the beeps on altimeters? I use a sethoscope because I cannot wear my hearing aids on the field. Some brands allow the use of an LED.

It seems so simple to develop.
 
That would be great if someone could develop a device with a small LED screen that would listen to the beeps and project it onto the screen. Even one that you could tailor to individual altimeters that would show your prelaunch beep/status also. As I get older my hearing cannot compete with the ambient noises going on around me and sometimes have to rely on otherers to make it out. Even better if it could differentiate between two separate altimeters...

Sorry, didn't mean to hi-jack the subject. Wish I was good in electronics, I'd like to tackle that.

Eric
 
CW, if you don't mind me asking, why can't you use your hearing aids on the field? I use mine from the time I wake up til the time I go to bed, sans shower.
 
Separately, LEDs are becoming more commonplace. I need to sell my Raven2/3's so I can buy a R4 so I can utilize the LED output. Not many altimeters don't have LEDs anymore.
 
I wear hearing aids and I fully agree; I have to hold the rocket right up to my ear. I don't usually wear them at the field if I'm around a lot of people, too much ambient noise.

A listening device might not even need an LED screen, just four or five LEDs connected so that the louder the sound, the more of them light, sorta like a bargraph. It should be easy to distinguish short beeps from long ones, too.

I just googled and found this instructable. Looks simple enough, might do the trick.
https://www.instructables.com/id/Sound-to-Light-Control-Circuit/
Best -- Terry
 
Slight side-step: some altimeters allow you to program the beep frequency.
This REALLY helped a flying buddy as we could tune to a frequency he could hear.
 
Missile Works just announced the new RRC2L and an LCD readout package.

You would have to remove the sled from the av bay to connect the display to the alt but you can visually read the data and program the events.

Have one of the packages in my shopping bag...
 
We have a new widget actually that can circumvent disassembly of your airframe/av-bay when using the RRC2L, RRC3, or RTx...

We're calling this widget the the "Airframe LCD Port Adapter". This can protrude thru your airframe, switch band, or av-bay bulkhead to provide an external connection to the internal LCD port, thus minimizing or avoiding disassembly.

Now this does require you protect the connector from dirt and debris, and this could be as simple as a tape wrap or something as extravagant as dedicated door or cover over the top of this thing: Airframe LCD Port

[Edit] pic added for illustration:
20200401_103329.jpg
 
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This "listener device" may be harder to implement than you think. The TeleMega for instance has such a fast beep sequence, that although I can hear it, I find it hard to distinguish each separate beep in the sequence.
 
It should be very easy to light an LED along with the beeps. Maybe a counter that displays the number.

I will ply with it as I get to it. Ham radio Field Day is this weekend, so my hobby time is tied up for a few days.
 
The Missileworks RRC3 has an option to program the AUX port to lite an LED in time with the beeps. I use it on most of my rockets due to it being hard to hear the heel tones.
 
The Missileworks RRC3 has an option to program the AUX port to lite an LED in time with the beeps. I use it on most of my rockets due to it being hard to hear the heel tones.

Yes indeed, and one can always run our Bluetooth Module with an RRC3 or RTx for a fully wireless experience.
 
You can buy very cheap sound-activated modules on ebay with built in LED's which light up based upon SPL. They are less than two dollars, and perfect for what you are looking for.

1592876692047.png


ebay listing

The listing doesn't say it, but it comes as a kit. That is a good thing, as you could solder the microphone on the opposite side of the board and just put it against the airframe. Chuck, I'm sure you could design a small 3d printed enclosure which would include the battery
 
Another option might be to use some kind of wireless microphone to pick it up... one of those little FM modules and an FM radio (if you can still find one...) should work as long as you don't need very much range (30' or less).
 
We have a new widget actually that can circumvent disassembly of your airframe/av-bay when using the RRC2L, RRC3, or RTx...

We're calling this widget the the "Airframe LCD Port Adapter". This can protrude thru your airframe, switch band, or av-bay bulkhead to provide an external connection to the internal LCD port, thus minimizing or avoiding disassembly.

Now this does require you protect the connector from dirt and debris, and this could be as simple as a tape wrap or something as extravagant as dedicated door or cover over the top of this thing: Airframe LCD Port

[Edit] pic added for illustration:
View attachment 421493
Added to the shopping bag.

Thanks, Jim.
 
You can use an app that performs spectral analysis to visualize the beeps.
1592906549650.png

The sequence of 3 beeps can easily be seen, at least indoors. Spectroid was used to for that.

One could write a custom app that decodes the beeps.

A micro controller based solution is possible too. There are examples that a reasonable motivated maker could use as a starting point:
https://learn.adafruit.com/fft-fun-with-fourier-transforms/tone-input
As with many products, cobbling together something quick shouldn't be that hard, but a system that works reliably with different altimeters on windy days etc. will take more time.

Reinhard
 
With other alt manufacturers jumping in this thread, the Marsa33 had a bright Cree led on the board that will be visible from a hole in the avbay. If you don't want the open hole you can use a short length of acrylic rod to act as a light pipe.
 
There is 100.0% probability that someone could throw together a simple smartphone app to do this. And for someone accustomed to doing any sort of audio or signal processing, I'll bet it would be a fairly easy task.
 
You could even have short bursts of data that a phone could pick up. After the beeps, a little burst of data. Encode it via any of the old modem protocols. Put a phone near it and it will decode it. At the noise level we are looking at, with good error correction we might get a couple hundred bits, which is certainly useful.

You could even add a small microphone to the altimeter, and then implement the Bell 101 protocol to have a communications link to the altimeter.
 
Why aren't ALL flight computers Blutooth capable? Just seems a no-brainer as opposed to listening/countingbeeps.
Surely cheap to add to the board, ala FlightSketch mini- not a deployment device but reliable, easy to use.
 
Why aren't ALL flight computers Blutooth capable? Just seems a no-brainer as opposed to listening/countingbeeps.
Surely cheap to add to the board, ala FlightSketch mini- not a deployment device but reliable, easy to use.
Territory is the main reason, a bluetooth is huge compared to the rest of the components on a board, programming space might be an issue as well as some chips only have so much space on them for additional firmware programming. Cost is yet another reason, a Quark wouldn't be $20 anymore, it might be $25 or $30 and nearly doble in size.
 
Territory is the main reason, a bluetooth is huge compared to the rest of the components on a board, programming space might be an issue as well as some chips only have so much space on them for additional firmware programming. Cost is yet another reason, a Quark wouldn't be $20 anymore, it might be $25 or $30 and nearly doble in size.
Like the Quantum... yes, double in size, and more money. But it also has a lot more flash on board, and more memory, so you can save flight data and do things that you can't with a simple deployment controller (like airstarts). WiFi takes a lot more power too... BTLE takes much less power, but you have to write an app for each platform, whereas you do not with a WiFi/browser architecture. Being the lazy weenie I am, I took the easy way out with the Eggtimer wireless altimeters... all the work is done in the altimeter, nothing on your device. That way I didn't have to spend two years learning iOS and Android programming.
 
Territory is the main reason, a bluetooth is huge compared to the rest of the components on a board, programming space might be an issue as well as some chips only have so much space on them for additional firmware programming. Cost is yet another reason, a Quark wouldn't be $20 anymore, it might be $25 or $30 and nearly doble in size.
Well, huge is in the eye of the beholder, I guess. Hopefully Russ won’t mind if I post this picture. This is a test unit of the FlightSketch Comp (competition version) that I’ll be test flying at BMR’s launch tomorrow. It’s functionally identical to the current FlightSketch Mini. That’s the tip of a Pentel 0.5mm mechanical pencil pointing to the bluetooth module on the board. It still dominates the board, just as the bluetooth module does on the Mini, but the whole thing is really tiny. The power connector on the bottom of the board in the picture is a 1.25mm spacing socket like those used on ultra micro RC airplanes.

AD4805CA-442E-43E9-8465-2F6796A93A95.jpeg

The software fun Cris refers to is certainly a consideration, though.
 
Well, huge is in the eye of the beholder, I guess. Hopefully Russ won’t mind if I post this picture. This is a test unit of the FlightSketch Comp (competition version) that I’ll be test flying at BMR’s launch tomorrow. It’s functionally identical to the current FlightSketch Mini. That’s the tip of a Pentel 0.5mm mechanical pencil pointing to the bluetooth module on the board. It still dominates the board, just as the bluetooth module does on the Mini, but the whole thing is really tiny. The power connector on the bottom of the board in the picture is a 1.25mm spacing socket like those used on ultra micro RC airplanes.

View attachment 421912

The software fun Cris refers to is certainly a consideration, though.
Maybe I should have clarified deployment altimeters, altitude only alts can be kept small, but when you have deployment alts there are a lot more components. I own two FS Mini's, and they are quite small. Based on who was askingvthe original question and some of the individuals responding as well as references to AV Bays I was reading the discussion as deployment type alts. A altitude only alt can just be attached to the shock cord if needed and not buried inside the airframe and they are much easier to hear than deployment alts.
 
CW, if you don't mind me asking, why can't you use your hearing aids on the field? I use mine from the time I wake up til the time I go to bed, sans shower.

That is a great question. I could if we outlaw sparkies. I have hearing loss and poor sound accommodation due to a blast injury. I no longer have the ability to tighten and loosen the ear drum. Loud noises are magnified by the hearing aid too much. I wore them once and was sick for 8-10 hours.
 
I actually purchased a couple of new Missleworks altimeters. I will give them a try. I will also that light sound device.
 
Maybe I should have clarified deployment altimeters, altitude only alts can be kept small, but when you have deployment alts there are a lot more components. I own two FS Mini's, and they are quite small. Based on who was askingvthe original question and some of the individuals responding as well as references to AV Bays I was reading the discussion as deployment type alts. A altitude only alt can just be attached to the shock cord if needed and not buried inside the airframe and they are much easier to hear than deployment alts.
Rich, I was reacting to yours (and Cris Erving’s) comments that adding bluetooth would greatly increase the size of the unit. I would think that for deployment altimeters, if they are really that much bigger/more complex then the effect of adding a tiny BLE component as on the one I imaged last night would be even less - from an overall device size perspective.

But John’s point about software is certainly a good one, spoken by one who knows and has been there.
 

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