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sandmantoy

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Has anyone adapted a digital read out for the beeps on an altimeter? I don't know if I even asked that question right. I have a hard time hearing the beeps and counting them especially if there is 2 altimeters singing away. I have seen small read out panels but I would not know where to start to make one give a reading of the beeps. Is it even possible with an endless loop of the beeps playing. This might not be a great idea for small rockets but bigger ones have more room :)

I like the way the small altimeters look but in a large rocket there is still room to pack your lunch in there too.
 

H_Rocket

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Tim

You could do it with a series of decade counters, a few gates and an LED panel. You could also use A PIC or other micro controller, but then you would have to write some code.

Post a question on our internal forum and Brad would probably jump on it
 

Adrian A

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Tim

You could do it with a series of decade counters, a few gates and an LED panel. You could also use A PIC or other micro controller, but then you would have to write some code.

Post a question on our internal forum and Brad would probably jump on it
I guess anything is possible, but I find that the code to beep out altitudes in an understandable way is more complicated than you might expect. Code for listening to and interpreting beeps would be even harder, I think.

Of course, if you want to know the peak altitude (and a lot more) without listening to beeps, you can get a recording altimeter and download the data. I find that, especially at the larger launches, there are plenty of laptops around that could be borrowed if you don't want to take one to the field.
 

H_Rocket

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Adrian

My brute force idea would be a kludge at best, and having thought on it would not work as I first considered after a long day at work -> The individual beeps would be very difficult to decode as they would probably go through a counter circuit as hundreds of clock pulses.

Tim -> never mind!
 

ben_ullman

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Has anyone adapted a digital read out for the beeps on an altimeter? I don't know if I even asked that question right. I have a hard time hearing the beeps and counting them especially if there is 2 altimeters singing away. I have seen small read out panels but I would not know where to start to make one give a reading of the beeps. Is it even possible with an endless loop of the beeps playing. This might not be a great idea for small rockets but bigger ones have more room :)

I like the way the small altimeters look but in a large rocket there is still room to pack your lunch in there too.
First suggestion, tell everyone around you to shut up and put your ear right over the hole and plug the other.

Next, turn one altimeter off ;) :roll: Then turn the 2nd off and the first back on. Then average the two :p

Ben
 

sandmantoy

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Al, I was or have been thinking about this for some time and thought a counter would be close to what I wanted but I know just enough about electronics to get me in trouble lol. I have been looking around for parts to start tinkering with the idea and kinda learning on the way.

Adrian
That is where I stopped as soon as I read about writing code in a few articles :eek: Then I knew it was way over my head to figure out lol. I have been using the perfectflite MAWD for seeing the altitude or getting somebody else to see if they can read the beeps at the field.

:eyepop: That Marsa4 has some potential

My idea is to pick up the rocket after the flight and read the altitude. This would take some creative building to do so I don't think it would be that popular. Kinda like a James bond movie where you see the read out on some device they have to save the world from lol.
 

ben_ullman

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Al, I was or have been thinking about this for some time and thought a counter would be close to what I wanted but I know just enough about electronics to get me in trouble lol. I have been looking around for parts to start tinkering with the idea and kinda learning on the way.

Adrian
That is where I stopped as soon as I read about writing code in a few articles :eek: Then I knew it was way over my head to figure out lol. I have been using the perfectflite MAWD for seeing the altitude or getting somebody else to see if they can read the beeps at the field.

:eyepop: That Marsa4 has some potential

My idea is to pick up the rocket after the flight and read the altitude. This would take some creative building to do so I don't think it would be that popular. Kinda like a James bond movie where you see the read out on some device they have to save the world from lol.
I have a MARSA (ok my dad does :rolleyes: ) but I am using some thin plexiglas to create a window in his 10" Nike so we can read it and use a screwdriver to move the joystick.

That way we can see whats going on at anytime.

Ben
 

jderimig

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I have a MARSA (ok my dad does :rolleyes: ) but I am using some thin plexiglas to create a window in his 10" Nike so we can read it and use a screwdriver to move the joystick.

That way we can see whats going on at anytime.

Ben
Good idea. But beware that the baro sensor does not like direct sunlight, it will cause wide fluctuations in output and likely cause any baro channels to fire early. (PS any altimeter that uses the Freescale baro sensors are subject to this problem).

You will want to include a simple shade made of cardstock to keep the baro sensor shielded if you're window might allow the baro sensor to point at the sun.

--jd
 

jderimig

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Al,


You will have yours 2 weeks before NERRF, promise.:cyclops:

jd
 

ben_ullman

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Good idea. But beware that the baro sensor does not like direct sunlight, it will cause wide fluctuations in output and likely cause any baro channels to fire early. (PS any altimeter that uses the Freescale baro sensors are subject to this problem).

You will want to include a simple shade made of cardstock to keep the baro sensor shielded if you're window might allow the baro sensor to point at the sun.

--jd
Isnt the BARO on backside? If so it should be shielded by the rest of the PCB. Ill check it out and make sure its shielded.

Ben
 

blackjack2564

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The easiest thing to do is cover the buzzer hole with your finger, which will silence the noise from one altimeter while counting the beeps from the other.

Then cover the other one with finger while counting beeps for the first alt.


Some altimeters such as the missleworks mini can be programed with a deeper tone beep. This makes reading the two much easier as they sound totally different. Leave one factory set and change the tone on the other.
 

sandmantoy

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To many years in a machine shop with no hearing protection.

Hey Ben, you can mount it high up on the board so it is close to the window. Then light will only get on the LCD. Is that thing back lit? I mounted a volt meter readout close to the inside diameter just to see what would be left to seal off. This one is not going to have a window, it is just a experiment I am tinkering with on my I5. The bracket is just plywood with aluminum tape over it but it would not take much to put it in a window.
 

bobkrech

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There have been several altimeters with LCD displays. IIRC Olsen and a Canadian altimeter company used LCD displays.


Advantages:
  • Easier programing.
  • Easier program verification.
Disadvantages:
  • In order to read the display, you have to take the altimeter out of the rocket.
  • LCD displays are fragile compared with the rest of the components.
  • LCD displays add expense and weight to the altimeter.
Alternatives:


If your altimeter has a beeper...
  1. Series wire a two pin polarized connector in series with the beeper circuit.
  2. Use use a shunt to provide normal operations.
  3. Mount a small LED on your airframe and run a polarized cable and plug it into the socket.
  4. The LED will flash when the beeper beeps.
  5. Count the flashes.
  6. Most beeper circuits are current limited, so putting a LED in series does not effect the beeper operation or change the power requirement of the altimeter.
  7. May not work on altimeters using low voltage batteries because LEDs in series need to have a 1.5 to 3.5 volt drop to light up.
If your altimeter has an LED flasher...
  1. Wire a polarized connector in parallel with the LED
  2. Mount a small LED on your airframe and run a polarized cable and plug it into the socket.
  3. The LED will flash when the beeper beeps.
  4. Count the flashes.
  5. LED circuits are current limited, so putting a LED in parallel may reduce the LED brightness but should not significantly change the power requirement of the altimeter.
  6. Should work on altimeters using low voltage batteries if the same color led is used because paralled LEDs don't require additional voltage to light up.
In both of the alternative cases, you can count the LED flashes to get the altitude without taking the altimeter compartment apart, and as a bonus you have added a rather foolproof way to confirm proper altimeter configuration and operational status at power up on the pad in altimeters where the beeper or LED are use to confirm status at power-up before launch.

Bob
 

sandmantoy

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I don't mind the weight I like to fly heavy. I was looking at this up/down counter kit to mess around with this idea. I found a nicer one somewhere but I haven't found where I put the link to it lol. A 5"x 12" bay is pretty roomy place to put experiments in.

I was thinking about putting a LED so I could see it without taking the bay apart also.

http://www.electronickits.com/kit/complete/elec/ck1612.htm
 

n5wd

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To many years in a machine shop with no hearing protection.
I feel for ya - after almost 20 years on ambulances with their sirens, radios, and all kind of other hell-raisers, I shudder to think what my hearing profile looks like (and just like a guy, I won't find out until I absolutely have to!).

You might try something adapted from the deaf - a little sound-meter that flashes a light when the audio level hits a certain level. Put the microphone in a rubber cup that can seal ambient noises and turn it on and count the flashes. You could even restrict the bandwidth to that just around the frequency of the altimeter, if ya wanted to. Relatively simple and highly portable - no need to mount in the rocket - just stick it to the side of the payload bay and count the flashes.
 

KerryQuinn

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Here is one such product is available on the market - and it's relatively cheap.

The Quest How-High Altimeter (now also available a apogee) uses a red "blinkie" led flasher to blink-out the altimeter after flight. I've been using this altimeter all spring/summer and it works great - it is also tiny. The LED is easily seen even in very bright sunlight.

There is an optional display called the "See How" that interprets the blinks and turns them into a numeric readout. I hve not tried this device, and it is not sold thru Quest, but you can get it here:

http://www.wingedshadow.com/seehow.html

(Interestingly there is also a third device called the "How Fast" - which is a pitot tube air speed indiciator which will record your peak airspeed,but only up to 500 mph)

SH200[1].gif


HowHigh1-100x80[1].jpg
 

sandmantoy

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I was looking at that, I have not tried it yet. It is on the path to what I would like to have.
 
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