Deaf Above 3000 Hz. Looking for Solutions on EggTimer

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ecarson

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Hope some of you who are hearing impaired can relate, or even those starting to lose it.

I recently started working with an EggTimer, and using an app on my iPod touch, I can see the little
buzzer on the EggTimer is beeping at around 4000 Hz. Well, I have severe hearing damage, and
I'm totally deaf above 3000 Hz. Even a hearing aid doesn't do me any good, because I'm completely
deaf above that frequency, so making it louder does nothing.

Oh, I can understand most speech, but many percussive stop consonants such as d, p, k, t, and others
all sound the same to me. i.e. when somebody says cat, pat, tat...all I hear is the "a" part. I rely on lip reading
to make up for what I lose in speech. I hate telephones, because I lose the visual cues. So there's that.

No problem with vision, thank goodness. The red and yellow LED's work fine, and I am already going to
solder in the yellow LED extension. However, the "buzzer" extension is what I would really like to use. The
manual states it must be a piezo element, meaning I probably should not hook an LED to that output.

At any rate, is there someway I can get a visual indication of the beeper sounding? When I finally get
this thing to the launch pad, with all the wind and other racket, I want to be able to verify the operation.
I believe launch noise, car engines, PA loudspeakers, and the like would frustrate my efforts there.
I have no idea if the iPod app will work outside with the unit inside an avbay, but indoors with the room
quiet it works OK to tell me the beeper is sounding.

Any suggestions?
 

DavidMcCann

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I know missleworks altimeters have a low tone setting, and MARSA 54's have the ability to run an LED. I believe Perfectflite altimeters can have an LED installed...i may be remembering incorrectly.

No knowledge of egg timer stuff, but figured I'd share the rest. RRC2's are about 45 bucks.
 

MikeyDSlagle

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Send Chris at Eggtimer an email, maybe he can help. Maybe a secondary circuit to change the beep to a flash using a microphone or a wired in circuit with a transistor?
 

cerving

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I can probably create a special build for you with a lower buzzer frequency... email me at [email protected]
 

Voyager1

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If this is the standard Eggtimer RevD, then all you have to do for visual indication is to wire an LED with a series resistor (say, 500 - 1k ohms) onto the "BUZ" terminal pads on the edge of the board next to the "RDY" terminal, adjacent the buzzer. The LED will indicate exactly what the buzzer is sounding out visually. The inner pad should be connected to the LED anode (+).
 

Zeus-cat

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Are you in a club? I can't believe there would be anyone in my club who wouldn't go out to the pad to assist someone in this situation. Many of us help people new to low power, mid power and high power set up their first few launches at those levels. If you are not in a club can you find a buddy to be your ears?
 

snrkl

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I can probably create a special build for you with a lower buzzer frequency... email me at [email protected]
OK - the more I see, the more I want to send @cerving money for products..

Seriously @cerving: after looking at your site fir the first time last night, I like your sales system ("contact us, we want to chat first to make sure you get the right thing") so much, I am now planning something that flies high enough to warrant an eggfinder mini...
 

ecarson

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Thanks for the suggestions so far. In reality, my hearing only comes to anywhere close to normal at about 1000 Hz, which is well
below any buzzer I have seen. From 1000 Hz to 3000 Hz it drops off ski slope.

I like the idea of the LED with resistor to the "buzzer" pads, but only if there is no possibility of damage to the board.

I'm recently (2015) retired, and have been working on a complete scratch design and build to achieve Level 1. I am in Tripoli,
but have not yet joined a club. There are two prefectures of Tripoli I am considering right now to align with, but have not yet
decided which. Both are a 3 hour drive away from me (Huntsville, AL or Nashville, TN). I've attended a couple of launches this year
just to observe, and take photographs of the rockets and recovery configurations.

I built and launched quite a few low power rockets back in the late 1960's and early 70's. Then again in the early 80's while in
college. The idea of dual-deployment piqued new interest , as I lost a major portion of my early birds to winds aloft. I saw that
if done right, it was only a short walk to recover the rocket. As such, I don't see getting this rocket to a pad until late September
or October. I am using the EggTimer as a main, and an Adept DDC22 as backup.

I plan on attending Southern Thunder at Manchester this weekend (if storm Cindy doesn't scrub it).

I'll email the fellow at EggTimer to see if the LED and resistor is completely OK to use off the buzzer pads.
 

Voyager1

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... I'll email the fellow at EggTimer to see if the LED and resistor is completely OK to use off the buzzer pads.
Yes, it would be a sensible plan to check with Cris. I have actually connected an LED in this way to one of my Eggtimers and it appears to be fine. Whether this parallel connection strategy is electrically sound depends on the loading that the resistor and LED presents to the buzzer drive line from the processor chip. It might also depend on whether the installed buzzer is a simple piezo (or electromagnetic) buzzer, or if it has built in driver/oscillator circuit. If Cris can reprogram the frequency, it suggests the former type.
 

Lowpuller

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I like the visual cue as well. I use an Eggfinder TRS and a MW RRC2. Frankly when everything starts beeping you really have to listen hard to determine what is taking place.

There is a German guy that launches at Camden who builds his own altimeters. He runs the LED to the exterior of the AV Bay. You can see his LED flashing from the launch button so he knows his altimeter is working from a distance. I thought that was a really cool idea.
 

Steve Shannon

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Thanks for the suggestions so far. In reality, my hearing only comes to anywhere close to normal at about 1000 Hz, which is well
below any buzzer I have seen. From 1000 Hz to 3000 Hz it drops off ski slope.

I like the idea of the LED with resistor to the "buzzer" pads, but only if there is no possibility of damage to the board.

I'm recently (2015) retired, and have been working on a complete scratch design and build to achieve Level 1. I am in Tripoli,
but have not yet joined a club. There are two prefectures of Tripoli I am considering right now to align with, but have not yet
decided which. Both are a 3 hour drive away from me (Huntsville, AL or Nashville, TN). I've attended a couple of launches this year
just to observe, and take photographs of the rockets and recovery configurations.

I built and launched quite a few low power rockets back in the late 1960's and early 70's. Then again in the early 80's while in
college. The idea of dual-deployment piqued new interest , as I lost a major portion of my early birds to winds aloft. I saw that
if done right, it was only a short walk to recover the rocket. As such, I don't see getting this rocket to a pad until late September
or October. I am using the EggTimer as a main, and an Adept DDC22 as backup.

I plan on attending Southern Thunder at Manchester this weekend (if storm Cindy doesn't scrub it).

I'll email the fellow at EggTimer to see if the LED and resistor is completely OK to use off the buzzer pads.
My dad had severe hearing loss that started in WWII and wasn't helped by a lifetime of shooting and operating heavy machinery. It's amazing how many people respond by nearly yelling, not realizing that louder isn't always the answer.
Just so you know, the nice guy who mentioned making a custom build a few posts above (cerving) is the fellow at EggTimer. I've not met him but I'm impressed by how helpful he has been to people on the forums.


Steve Shannon
 

T-Rex

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On page 12 of the Rev D Eggtimer manual, it discusses adding an external LED that mimics the yellow LED on the board. I have done this on Fat Daddy, because the sled is mounted in a tube inside the nosecone, and it works great. I used a 'purple' led and can see it in the daylight.

I'll try and get a picture and upload it after while.....
 

r66astro

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I have the same problem.. Not so much the hertz just too low. I do not remember where I got them but I just install a bigger transducer. Now if I am close I can hear.
Bill
 

ecarson

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Mr. Erving at EggTimer got back with me today, and indicated that the LED and resistor solution is workable. Many
thanks for verifying this is OK to do.

I've just spent the last eight hours assembling the second unit myself. Not being extensively experienced with building
electronics of this sort, I was glad to have the first unit already assembled. A big thank you to Conner McGrath for that.

I must admit, I was very surprised when the unit I just assembled myself booted up in the terminal, and programmed
without problem. I was quite meticulous, following the instructions to the letter. I also referenced the other unit from
time to time to make sure. I triple checked it all. I also had excellent tools. A feedback controlled soldering station, and
some of that fine Kester 63/37 solder at 0.020" diameter. I also used MG Chemicals no-clean flux paste applied with a toothpick to the pads
very sparingly. It made a big difference.

Being up in years, I had to use 3.5X magnifiers on top of my glasses. I also used a 20X loupe to inspect every last solder connection,
and I did find a few that needed to be redone. I tested using the mini- Christmas tree light bulbs to simulate igniters. All worked
perfectly. I also might add, that a good dose of beta-blockers (for blood pressure) sure helped with the hand trembling.

I will find a suitable LED and resistor and try the suggested solution after I return from Manchester. For now, I'm beat...but happy.

The top unit is the Conner McGrath build, and the bottom is the one I finished myself about an hour ago.
053 (Large).jpg
 

Voyager1

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On page 12 of the Rev D Eggtimer manual, it discusses adding an external LED that mimics the yellow LED on the board. I have done this on Fat Daddy, because the sled is mounted in a tube inside the nosecone, and it works great. I used a 'purple' led and can see it in the daylight.

I'll try and get a picture and upload it after while.....
Good man Terry, if in doubt, read the manual! Any of these mods should be implemented with reference to the advice in the manual, or better still, from Cris.

With regard to the use of the "BUZ" output connection on the Eggtimer RevD, on page 12 it is stated that a piezo device can be connected to this output providing that the extra current load is less than 20 mA. This is in accord with the maximum DC output current for the ATMega328P processors' I/O pin of 40 mA. This means that if you have 2 similar piezo devices connected in parallel, the average current load for each device should be less than 40mA / 2 = 20mA.

If you were to instead connect an LED with a series resistor to the "BUZ" pads, you would need to ensure that the extra current load was less than the 20 mA limit. As an example, if you were to use a high efficiency red LED with a typical forward voltage of about 2V, then to have a maximum LED current of, say 15 mA, you would require a series resistor of about 87 Ohms (91 Ohms as a preferred value) as a minimum value. I would probably err on the safe side and use 130 Ohm for a 10 mA LED current, particularly if you only wanted to view it in close proximity to the Eggtimer, and not from the launch position.

Any of these undocumented mods come with the caveat that you do so at your own risk of possible damage to your Eggtimer. Personally, I'm happy with the precautions that I've taken in this case and it seems to work just fine.

As my club members constantly remind me - "What could possibly go wrong!".
 

mrwalsh85

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Are you in a club? I can't believe there would be anyone in my club who wouldn't go out to the pad to assist someone in this situation. Many of us help people new to low power, mid power and high power set up their first few launches at those levels. If you are not in a club can you find a buddy to be your ears?
There are several.... Hindrances... with this, if you will. 1 - it makes that person very dependent on others to fly their own rocket. 2 - It places liability on that other person -- "I swore I heard 3 beeps!"

I have the same problem. I am profoundly deaf. I speak well and hear/lipread very well. However I am still very deaf, to the effect that I use Video Relay Interpreting to make phone calls (via video interpreter).

I have modified most of my electronics to accept LEDs in place of a buzzer (when there is not an option for a LED output). Jim Amos at Missileworks and I discussed the options for his latest product offerings, and he was very willing to work with me. Many thanks for that. John Derimiggio of MARSA Systems has a LED output on his board as well.... I have yet to change over my Raven(s) but Adrian recently confirmed it is doable.

This is a thread that I posted on visual indications. I use this method as much as possible. https://www.rocketryforum.com/showthread.php?62779-Altimeter-Status-Indicators

I have the following electronics and used the stated method for visual indicators:

Adept22 -- removed Piezo Buzzer, wired in dropping resistor and LED.
Missileworks RRC3 -- programmed auxilary output to accept LED.
Missileworks RRC2+ -- removed surface mounted LED and wired in an external LED.
Stratologger SL100 -- External output allows LED. The LED they offer is ENORMOUS. I use small LEDs so I had to find my own connector. Not hard.
MARSA54L -- External output allows LED.

Raven -- not yet completed.

I normally use harness connectors so that I can remove the altimeter bay from the rocket. In the thread above, you can see how I mounted my LEDs. I didn't want to be looking around the av bay for a LED, let alone worry about orientation. I also mount my screw switches directly to the airframe whenever possible. It just makes it very easy to work with.

I have used these methods on many rockets, as small as a LOC HiTech45 up to my L3. I used a stiffy coupler as the av bay, and simply drilled out the stiffy and pressed in a LED. Works like a charm.

More than glad to help you out if you choose to utilize other altimeter offerings (no offense Cris -- I really enjoy your products. I have 4 eggfinders!).

Mike
 

OverTheTop

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ecarson, seems from your post you have done a very meticulous job of the assembly and done everything right from what I read. Good work.

Now we need to convince more people to attempt assembly of these Egg kits. The surface-mount soldering puts a lot of people off.
 

jrkennedy2

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The kits are challenging but that's over 1/2 the fun. The Quantum is nice one because you can look how things are going with a WiFi connection and browser.

+1 for kit-builds!
 

cerving

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Another alternative is to go with the Eggtimer Quantum rather than the Classic. It has a WiFi interface to your phone/tablet, so you get remote continuity and arming/disarming, from over 100' away if you wish. You also get remote deployment charge testing and data downloading, so you don't have to mess with the data cable. The buzzer on the Quantum is a buffered magnetic type, so it's significantly louder than the one on the Classic (which probably won't help you much because of your high-frequency hearing loss, but it is an advantage over the Classic).
 

ecarson

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Quick update here. I ordered kits of 1/4 watt metal film resistors and LED's online. They were pretty inexpensive for large assortments.

I removed the buzzer from the board, on suggestion from cerving, to provide a little more current to the "BUZ" pads. It was doing me
little good, having to use the iPod app to detect the sound. After experimenting with a few combinations, I finally hit on using a
3mm bright white LED, with a 680 ohm resistor. This is working good, as now I can see what the buzzer would be doing, except now it
is bright white flashes of light. I'll take it outside tomorrow in the sunlight to check it out, but I am fairly confident it will be visible.

Currently working on a vacuum chamber test system. I'll post that later on in a new thread. Using an old "Air-Vac" venturi pump, I can smoothly get to
25" Hg in about 6 seconds on a 1 quart Mason Jar. My chart says that is over 40,000 ft. above sea-level. It has held this vacuum now over
2 hours. Cobbled it up from stuff I had in the basement.
 
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