# Altimeters: Comparison guide

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#### azzie

##### Well-Known Member
2014 was a great year for electronics in rocketry - we've seen many new devices which are getting smarter, smaller and cheaper. With all the changes, it gets harder to keep track of all available options (don't get me wrong - it's a good problem to have!).

My attempt to simplify it resulted in an extensive list of all currently available model rocket altimeters and their parameters, such as dimensions, weight, sensors being used, interfaces, pyro options, battery and voltage requirements, etc. All data was compiled from vendor datasheets and manuals. If it's something TRF community finds useful, I'd keep maintaining it.

Link: Model rocket altimeters: Comparison guide.

Now here's how you could help: I'm missing some data for few altimeters (look for question marks), mostly related to dimensions and recording functions. If you have one, measure it / post a file with a recorded flight, and I'll update the guide accordingly.

All comments (except negative ones) are welcome!

--Alex
https://RocketsEtc.com/

#### BEC

##### Well-Known Member
That's brilliant! I may well cite this in my NARCON presentation on this subject.

I can get you some of the question marks....and at least one correction...which is saying that the Estes altimeter fits in BT-20 is a bit of a stretch....it will go in one, but only if you let it distort the tube some.

Also - there are two form factors of the Jolly Logic devices. The current ones are larger than the originals - I haven't checked yet to see which numbers you have. Since I'm sure there are lots of the older devices out there, it might make sense to list both types.

Finally - on the PC column - it might be useful (but further complicating) to note what platforms are supported. For example, PerfectFlite's software is available for both Windows and MacOS. Altus Metrum supports both of those plus Linux.

Added later: for the tube-fit column: do you want just Estes tube size designations? For example the current Jolly Logic devices fit in Centuri/Semroc ST-8 quite easily....but don't fit in BT-20 at all. So would you prefer to quote that as "BT-50"?

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#### H_Rocket

##### Death by Powerpoint
It might be worthwhile to add a column indicating whether the product is still available.

#### Woody's Workshop

##### Well-Known Member
TRF Supporter
This is perfect idea. For people like me trying to get into the MPR & learning DD, this would be the "Go To" Tool and save much valuable time looking it all up.

#### azzie

##### Well-Known Member
there are two form factors of the Jolly Logic devices. The current ones are larger than the originals
It might be worthwhile to add a column indicating whether the product is still available.
I'm planning to list only currently available devices (i.e. that can be immediately purchased from vendor or reseller). I'd like it to be a research tool for "new projects" rather than for maintaining history.

Finally - on the PC column - it might be useful (but further complicating) to note what platforms are supported.
That's a good idea! I could use platform abbreviation in "PC" column instead of checkmark. "W,M" will indicate "Windows,Mac"... Let me think about it.

do you want just Estes tube size designations?
I think we should stick with Estes BT classification - it's a sort of "gold standard" of diameters that everyone's familiar with.

#### CarVac

##### Well-Known Member
You misspelled EggTimer as Eggimer. It's kinda funny to pronounce that.

Otherwise, that's an incredibly detailed and informative chart. Great work!

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#### CarVac

##### Well-Known Member
I think we should stick with Estes BT classification - it's a sort of "gold standard" of diameters that everyone's familiar with.
Personally, I have no clue what the Estes BT sizes are...

#### wfcook

##### Mayhem Rocketry, LLC
Great chart! A couple of suggestions:

It would be useful in the sensors/accel column to note the maximum acceleration that the sensor can handle. The Raven3, for example, comes in two versions (70G and 200G), while the Altimeter2 can handle 24G.

Also of interest would be whether each altimeter is approved for various rocketry competitions.

Sent from my iPhone using Rocketry Forum

#### Buckeye

##### Well-Known Member
TRF Supporter
Personally, I have no clue what the Estes BT sizes are...
+1 to that.

BT-50? That tells me nothing. 29mm, 1.52", etc. are numbers I can get my arms around. Since these electronics usually go into MPR and HPR rockets, I suggest using proper dimensions (preferably mm) as the "gold standard" for diameter. Time to move on from 1973.

Overall, very nice chart. Great effort. Thanks.

#### nute

##### Well-Known Member
Great chart!!
One thing I see, at first glance, is that the firefly reports speed in mph on landing as well as altitude.

Nate

#### BEC

##### Well-Known Member
Since these electronics usually go into MPR and HPR rockets, I suggest using proper dimensions (preferably mm) as the "gold standard" for diameter.
The ones that do deployment charges - yes. For the others, the intended application is all the way down to 1/2A-powered LPRs and some (FireFly, MicroPeak, Adrel ALT-BMP, PicoAlt P1) are all small enough to be used that way. I've flown a TeleMini in a BT-50-based LPR - an Estes Nova Payloader. It's cool to get the downlinked altitude and flight phases that way.

BTW, BT-50 is 24mm....

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#### Winston

##### Lorenzo von Matterhorn
2014 was a great year for electronics in rocketry - we've seen many new devices which are getting smarter, smaller and cheaper. With all the changes, it gets harder to keep track of all available options (don't get me wrong - it's a good problem to have!).

My attempt to simplify it resulted in an extensive list of all currently available model rocket altimeters and their parameters, such as dimensions, weight, sensors being used, interfaces, pyro options, battery and voltage requirements, etc. All data was compiled from vendor datasheets and manuals. If it's something TRF community finds useful, I'd keep maintaining it.

Link: Model rocket altimeters: Comparison guide.

Now here's how you could help: I'm missing some data for few altimeters (look for question marks), mostly related to dimensions and recording functions. If you have one, measure it / post a file with a recorded flight, and I'll update the guide accordingly.

All comments (except negative ones) are welcome!

--Alex
https://RocketsEtc.com/
VERY nice! Thanks. One thing you might add - a gyro column. I know of a few devices that have them - the Telemetrum series and the upcoming Apollo:

https://carbonorigins.com/apollo

With the Apollo, the orientation of the rocket in flight will be shown with a 3D graphics rendering by the data reduction software. I suspect gyros could be useful to supply good primary sensor data to show any instabilities during flight along with the mode(s) of those instabilities.

#### kweaver

##### Always willing to learn!
TRF Supporter
Great chart!
Thanks for all the work!
Agree on mm suggestion.
Maybe you could possibly do: >BT5/13mm, >BT20/18mm, >BT50/24mm, >BT55/29mm etc.
Would really help us bodytube number challenged.

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#### azzie

##### Well-Known Member
Thank you for good words and suggestions! Few improvements:

* Some vendors charge extra for USB cables and RF receivers, but altimeter is not fully functional without them. Added a column with "Kit" price that includes PC cable / RF receiver, where applicable.

* Changed body tube size from Estes to millimeters. If you hoover the mouse over the value, tooltip will show BT-xx size as well.

* Added supported operating systems (Win, Mac, Linux)

#### Moon Knight

##### Well-Known Member
I would love to see which are competition certified, too. Thanks for the great work.

#### BEC

##### Well-Known Member
I would love to see which are competition certified, too. Thanks for the great work.

#### azzie

##### Well-Known Member
Can someone make this thread sticky?

#### kjhill

##### New Member
I am going after my lvl3 cert and is looking at buying my main flight computer. I will use my old and trusted computer from my lvl 1 and 2 flights for my backup but need to buy my main. my back up is a stratologger perfectflite and it worked great for my lvl1 and 2. it should work great for my back up. now for my main there are many to look at can someone tell me what they like. I am looking at Marsa54L and the G-Wiz HCX

#### ksaves2

I am going after my lvl3 cert and is looking at buying my main flight computer. I will use my old and trusted computer from my lvl 1 and 2 flights for my backup but need to buy my main. my back up is a stratologger perfectflite and it worked great for my lvl1 and 2. it should work great for my back up. now for my main there are many to look at can someone tell me what they like. I am looking at Marsa54L and the G-Wiz HCX
What do you want to do in the future? The Marsa 54 is certainly a nice unit. I don't know how hard it is to order a G-Wiz HCX. Hawk Mountain has them listed.
How much you wanna spend? The ivory tower boys will say, "You need two different altimeters." Balderdash!!! You could use a second stratologger and use an apogee delay on the second unit for backup. That's what it's for.

Then again, if you want something that is "data rich" a Raven III is nice to download all sorts of interesting information after the flight and you don't have to buy any "special" interfaces to do so. (Ditto that for the Marsa 54L)

I say again, "What do you want to do in the future?" This is relevant to what you might buy. If you're good with a soldering pencil, you could build an EggTimer TRS and have a two channel controller AND gps tracker for $140.00. Can't beat that price. Kurt Last edited: #### kjhill ##### New Member I would like a data rich unit. I would like to know how close to the sound barrier I was and if I break it. I don't know that much about Featherweight. #### azzie ##### Well-Known Member I would like a data rich unit. I would like to know how close to the sound barrier I was and if I break it. Go to altimeter comparison guide. Look for altimeters with "Record" function. You will see "Click!" in the Record column. Well, click on it and it will tell you which information is recorded by each altimeter. #### ksaves2 ##### Lifetime Supporter TRF Lifetime Supporter I would like a data rich unit. I would like to know how close to the sound barrier I was and if I break it. I don't know that much about Featherweight. Weeeeell, With a good ol' MAWD on an L1400 flight in a stretched 3" Wildman rocket, I saw a little "blip" that was significantly more than baseline noise when it was expect to be going Mach one on a simulator and another when it dropped below Mach 1. I've had a lot of subsonic flights with the MAWD and never saw anything like this before. I suspected it was possible to see on the baro/altitude the shockwave passage but didn't know if it was strong enough to "see through the noise". Well, it was with that rocket. Oh, the Featherweight Raven III will record plenty of information for you to ponder. Kurt Last edited: #### John Beans ##### Founder, Jolly Logic TRF Supporter Tweak: Jolly Logic AltimeterTwo memory is 100 flights. #### John Beans ##### Founder, Jolly Logic TRF Supporter Alex, Here's the data for AltimeterThree. Can we please add an interface column for "Mobile"? No plans to support PCs in the field, and we also have more products coming that leverage mobile devices (phones and tablets). Addition: Jolly Logic AltimeterThree. Price:$99.95
Max alt: 29,500 ft <-- which is calibrated (not max-at-reduced-accuracy) altitude, as we prefer
Same dimensions as AltimeterOne and AltimeterTwo.
Sensors: Baro + 3-axis acceleration
OS: Apple iOS, Android
Memory: &#8734; or n/a (only limited by memory on phone/tablet)
PostFlight & Record: graph of altitude, graphs of acceleration (X, Y, Z, and Total), max altitude, flight duration, flight notes
Battery: built-in
What is comp? Temp-compensated? Yes.

Ideas for future columns, I guess once they become more common:
2. Export formats: Excel, Open Doc, csv, text, binary, jpg, png, gif, etc.
3. Flight notes

#### Randy'sRocketShop

##### Member
Alex,
Thanks so much for publishing this! This will save some time with my upcoming DD project.

#### BEC

##### Well-Known Member
I think "comp" is "approved for NAR competition" which the A3 isn't.

#### John Beans

##### Founder, Jolly Logic
TRF Supporter
I think "comp" is "approved for NAR competition" which the A3 isn't.
Thanks. I could not figure that out. You're correct, of course.

#### azzie

##### Well-Known Member
Here's the data for AltimeterThree.
Thank you John!! I updated the list. If I missed anything, please PM and I'll make it right.

Mobile and social media are definitely getting traction with altimeters. I'll think how to add it... Do we have onboard camera that posts its video on youtube, even if it's stuck in a tree?

#### John Beans

##### Founder, Jolly Logic
TRF Supporter
Alex,
Cool, thanks.

P.S. Don't forget to update AltimeterTwo to 100 flight memory, please.