Lighest Available Altimeter That Records Flight Duration

[BEC]

I've been thinking about this some more, and even if I found or custom ordered some tiny batteries with the 1.25 mm PicoBlade connectors to sell with these, they wouldn't be compatible with my existing charger anyway, since it's designed for the 150mAhr+ batteries that I sell and charges with a 125 mA of current. So if I take this on I'm signing up for sourcing tiny batteries and making a new charger. In that case, using the SH connector would be the right way to go, since it's even smaller and each class of battery would have its own connector and place to charge it. Adding a new charger would add to the cost, though.

Of course one only needs to buy one charger to support several altimeters. FlightSketch also created a tiny charger to handle those little 9mAh cells...and its lowest charge rate is 15mA, so still pushing things a bit.

But an ION is $20... so if you lose it you're not out more than the cost of an E12 motor 3-pack. The other altimeters are a lot more..

Indeed. $20 plus the cost of the cell (and assuming one has an appropriate charger already).

There was a time when the FS Mini was $19, but we all knew that wasn't sustainable. I don't think that's what happened to FlightSketch, though. Something else is going on in his real life I'm positive. I just hope Russ and his family are OK.

For a model that has the room and the mass budget for the ION and a 110 mAh cell, and is OK with the slightly different results he/she will see relative to others (as we've discussed ad nauseam via emails) it works well.

BTW Bernie, if you remove that little yellow tab over the buzzer it will be a whole lot louder. The manufacturers put them there to prevent flux intrusion when they're being soldered.

Oh, I know. That's why I leave it on there. It's plenty loud as it is.

 

[Art Upton]

But an ION is $20... so if you lose it you're not out more than the cost of an E12 motor 3-pack.

Do they make those still ?

But I agree, if you lose one it's $20 not much in the 'game' of things competitive.

 

[BEC]

Do they make those still ?

But I agree, if you lose one it's $20 not much in the 'game' of things competitive.

Well, actually, YOU make it (well assemble it). But yes, the kits are available.

It is not accepted for NAR contest use and it's so big and heavy relative to those which are, that I can't imagine it being used that way.

 

[Art Upton]

Well, actually, YOU make it (well assemble it). But yes, the kits are available.

It is not accepted for NAR contest use and it's so big and heavy relative to those which are, that I can't imagine it being used that way.

See the bolded part of my question... Do they make a 3 pack of E12s anymore

 

[BEC]

See the bolded part of my question... Do they make a 3 pack of E12s anymore

View attachment 676476

Ooops....

But yes, they do: https://estesrockets.com/products/e12-6-engines

And Cris is right, an ION and a cell to power it is about the same price.

 

[Art Upton]

Ooops....

But yes, they do: https://estesrockets.com/products/e12-6-engines

And Cris is right, an ION and a cell to power it is about the same price.

OK, those are the old packs, weird they still have them in stock to sell?

The newest come in re-sealable 2-packs now with the new date codes, as do the D12s

 

[BEC]

Indeed....though at Hobby Lobby's prices you can get two of those four-packs for the retail price of the 3-packs on the Estes site and therefore 3-packs at a place like HobbyTown USA or an independent hobby shop, if such things still exist.

I got some C11s and D12s from the recall with those new date codes, and it turns out that I have some B6-4s and C6-5s from recent bulk packs that have a sort of in-between date code that has an extra character over the ones we've been seeing for the past 15+ years. But that's a subject for a different thread, I think, than one about altimeters.

 

[Art Upton]

Indeed....though at Hobby Lobby's prices you can get two of those four-packs for the retail price of the 3-packs on the Estes site and therefore 3-packs at a place like HobbyTown USA or an independent hobby shop, if such things still exist.

I got some C11s and D12s from the recall with those new date codes, and it turns out that I have some B6-4s and C6-5s from recent bulk packs that have a sort of in-between date code that has an extra character over the ones we've been seeing for the past 15+ years. But that's a subject for a different thread, I think, than one about altimeters.

No E motors at my Hobby Town, very little in rockets now after they moved to a new location

 

[dpower]

What would you guys think about a competition altimeter that is 0.76" x 0.355" with no mounting holes but with:

• battery connector
• Bluetooth to the Featherweight UI phone app
• 32G accel
• Gyro
• Baro sensor
• 2 LEDs
• 16 Mbits flight data (1/8 of the Blue Raven, same as the Blue Jay)

The thing I'm most unsure about is which battery connector to use. I like the 1.25mm picoblade connectors, but the smallest available batteries are now using JST-SH 1mm pitch connectors. I'm not enthusiastic about taking on another battery standard and making a new charger for it.

Here's an example: https://www.sparkfun.com/products/25270. Its datasheet says less than 2 grams. I may buy a few to see how much less. Or maybe I could get some tiny batteries made with the 1.25mm picoblade connector I'm already using.

The Flightsketch used a 9 mA battery with the 1.25mm picoblade connector, says it's 0.49 grams: https://flightsketch.com/store/catalog/9mah-lipo-battery_502/

Count me in for multiples, and a number of NRC fliers in my club would be interested. The comp is great, but unobtainable, I have just one left, will use it for this season's NRC while it's still approved. Having BT is a real help when trying to locate a device after it's landed. The Adrel is a non-starter, I'm not interested in buying a windows computer just for that device. I've been getting by with MicroPeaks, but they won't fit in a BT-5 without squishing it flat, and FireFlys for BT-20 and larger models. I always use a tether, so I highly recommend a single hole somewhere. That's one downside of the FireFly. The connector wouldn't matter to me, as long as it's reasonably robust, won't rip off the board when removing to recharge, and ready-made chargers are available. The cost of a charger is negligible for competition fliers, where altimeters sometimes end up being a consumable!

We NRC fliers desperately need a BT-5 bluetooth altimeter!

 

[lr64]

I just checked the local Craigslist. One Windows 10 laptop at $20, though it needs a new battery. One at $30. A bunch at $50. I wonder if Adrel is going to update when support for Windows 10 ends. Of course, it will take up space, and it will turn into a pumpkin on 10/14/25

 

[lr64]

BTW, what is the mean number of flights between CATOs for a rocket that uses 3 E12s? It had better have an inexpensive altimeter! ;-)

 

[shockie]

Just for your information, the NCR Adtel MaxAlt software won't run on windows 11.

I get an error message saying a .dll is not found.

It only runs on win 10, and unfortunately there's no win 10 compatability mode in win 11. Yet.

I may install win 10 in a VM and see if the USB data port is seen . VMware usually has pretty good USB pass thru.

 

[BEC]

Hmmmmm.....I'd been curious about that. I wonder what the folks at Adrel are planning to do. The barometric sensor they use is also now obsolete.

 

[Gus]

Adrian,

The review and advice given by Bernard is magnificent. His notes are incredibly complete and I agree with everything he has written here, having personally flown all the mentioned devices. Definitely rely upon Bernard for his incredibly thorough and well-reasoned input.

Bernard and I know each other well and I'm pretty sure he will agree that virtually no one flies more competition altimeters or pushes them harder than me. I flew 3 record attempt flights just today (lost one altimeter). And I've lost more altimeters in more countries than many of you have been to, LOL.

My two cents. All I fly anymore are Adrel BMPs. At 1.6 g and small enough to fit in a 10 mm tube you can fit the unit and battery inside a BT-5 vacuform nosecone. The Adrels have been around 15 years and are just stupidly reliable and simple to use. The tether Bernard mentions was my invention and I often use it to simply tie the Adrel to a nosecone inside a body tube, no separate altimeter compartment required. I always use a bit of wadding below them but have never had one damaged by ejection gasses. My daughter actually had one run over by a truck and it still read just fine. Like I said, they are just ridiculously reliable. Prepping my altitude attempts often takes 2 - 3 hours (yes, for what are basically 3 FNCs with a streamer). So to fly one of these attempts successfully and then get an altimeter no-read is just not acceptable.

Your proposal sounds very exciting. Regarding electrical connectors, I use the smaller connectors on micro tracking devices but, for robustness, prefer the Adrel sized connectors. Not just less breakable, but easier on my geriatric fingers and eyes.

For competition make sure that whatever you produce has easily downloadable flight graphs. Non-graphing altimeters are not allowed for record setting. The FS Comp had bluetooth downloadable flight graphs but they got downloaded to an online site which I always found cumbersome and confusing. I also found it confusing at competition events to call up the altimeter on my phone and see 6 other competitors listed.

I understand your frustration with the certification process you went through for TARC. But the reason the Adrel has been the only approved FAI altimeter, until just recently, is that everything FAI is so hugely bureaucratic and opaque.

There is currently a brand new Serbian altimeter we will be required to use at next summer's FAI World Spacemodeling Championship which was very secretly certified and for which we have received no data. It is larger than the Adrel and weight is roughly double the Adrel. It broadcasts its data inflight which sounds nice but prevents the use of carbon airframes which is a real problem for many of us. We are currently unable to purchase any of the units online but were told by our British colleagues who went to the European Championship that we could supposedly purchase 10 altimeters and one receiver for 4500 euro ($5000)! Needless to say, we have so far declined so we will probably first get to use them in the actual contest next summer. Data sheet for this altimeter is attached below.

Again, your proposal to create a new competition altimeter is really exciting. Please feel free to count on me, as well as Bernard, for any advice or help I can give.

Steve Kristal

 

[shockie]

What would you guys think about a competition altimeter that is 0.76" x 0.355" with no mounting holes but with:

• battery connector
• Bluetooth to the Featherweight UI phone app
• 32G accel
• Gyro
• Baro sensor
• 2 LEDs
• 16 Mbits flight data (1/8 of the Blue Raven, same as the Blue Jay)

The thing I'm most unsure about is which battery connector to use. I like the 1.25mm picoblade connectors, but the smallest available batteries are now using JST-SH 1mm pitch connectors. I'm not enthusiastic about taking on another battery standard and making a new charger for it.

Here's an example: https://www.sparkfun.com/products/25270. Its datasheet says less than 2 grams. I may buy a few to see how much less. Or maybe I could get some tiny batteries made with the 1.25mm picoblade connector I'm already using.

The Flightsketch used a 9 mA battery with the 1.25mm picoblade connector, says it's 0.49 grams: https://flightsketch.com/store/catalog/9mah-lipo-battery_502/

Could you just reverse-engineer the FS mini or comp? But using newer IC? "we can rebuild it, faster and stronger".

I could use at least 10 FS comp or their replicas, right now.
Of course, at a reasonable price.

Does anybody remember Robert Dehate(s) Pico Alt altimeters from the early 2000's. Circa 2005

I had several of his products back then.

 

[WillMarchant]

Does anybody remember Robert Dehate(s) Pico Alt altimeters from the early 2000's. Circa 2005

I had several of his products back then.

Robert shows some in stock at https://cart.amwprox.com/index.php?...category&virtuemart_category_id=77&Itemid=474

 

[Gus]

Could you just reverse-engineer the FS mini or comp? But using newer IC? "we can rebuild it, faster and stronger".

I could use at least 10 FS comp or their replicas, right now.
Of course, at a reasonable price.

Does anybody remember Robert Dehate(s) Pico Alt altimeters from the early 2000's. Circa 2005

I had several of his products back then.

Shockie,

Just curious why you need 10 FS Comps.

Steve

 

[cerving]

This is great info and super helpful to me.


...
As for the apogee filtering, about 10+ years ago I put in a bid to provide altimeters for TARC, and I prototyped and flew several units that included a pretty effective filter for getting true apogee in the face of transients. I made a rocket that flew several of the units at the same time to demonstrate the repeatability. Unfortunately, the person who was running that selection process did it with a vacuum chamber that had a pressure profile that had nothing to do with a real flight, so he got garbage results and my altimeter was not selected. It was such a frustrating experience that I have stayed away from competition altimeters ever since. This might be a good time for me to try again on a project like this.

Adrian, yup, vacuum box tests are good for functionality testing only... they aren't a very good flight simulation. I would think that if they were going to "certify" your altimeter that they would have to actually fly it. I know that Bernard Cawley actually flight tests them, if you wanted to make a competition or TARC certified altimeter he would be the one to go to.

 

[WizardOfBoz]

But an ION is $20... so if you lose it you're not out more than the cost of an E12 motor 3-pack. The other altimeters are a lot more...

Also one can download the data with a phone.

 

[BEC]

Wow, thanks Steve and Cris for your vote of confidence in my altimeter testing.

Yes, I do fly them. I have a little vacuum bottle thing that I got from Tommy Billings at Adept some time ago that I use for initial checks but other than that it's take 'em out and put 'em in a rocket and fly them, often alongside other known good devices for comparison's sake. Then I bombard the maker with more notes than I suspect he wants. Keith Packard, John Beans, Russ Parrish, Cris Erving and Marcelo Goluboff all know this from experience.

 

[cerving]

OK, those are the old packs, weird they still have them in stock to sell?

The newest come in re-sealable 2-packs now with the new date codes, as do the D12s

View attachment 676490

Ah... haven't bought any of them in awhile. I have a bunch in my LPR 18/24mm box... all in 3-packs.

 

[Art Upton]

Ah... haven't bought any of them in awhile. I have a bunch in my LPR 18/24mm box... all in 3-packs.

I like these new packs for storing easier then the bubble packs. Plus no plastic to come loose and loose ignitors. And in a Range Bag at the field, the resealable pouch is nice. I will save them when empty to put older bubble pack motors in after breaking the 3 pack open, put the other two in the resealable pouch.

While I have lots and lots of range boxes from over the years I used to load my truck up with to have just about everything I did or didn't need with me...I have one of these I have been using this year for 'Just what I need' when getting a ride to the local launch.


https://www.harborfreight.com/tool-...ags/12-in-tool-bag-with-21-pockets-61467.html

 

[shockie]

Shockie,

Just curious why you need 10 FS Comps.

Steve

Spares. In case the 1st one flys away.