RECOMMEND A GOOD ALTIMETER

[redlinepilot]

This will be used for mid power flight in rockets with 2" to 4" body tube. I don't have any experiance with the altimeters presently on the market so I'm reaching out for suggestions.

[cjl]

Featherweight Raven?

What features are you looking for?

[stantonjtroy]

Not trying to hijack this thread but I was about to post the same question. In addition to the question posed, MY specific intrest is in duel deployment. Not too worried about data recording or reporting just reliable Apogee then main at X feet. I have an Adept ALT-50K whitch I've had for years but am just getting ready to use for the first time. I'm looking to aquire a couple more altimeters and have noticed there is a lot more to choose from since my last purchase. any thoughts?

[troj]

For a first altimeter, it's hard to beat the PerfectFlite MAWD. The RRC2 Mini is a close second.

Lots of others on the market that do great things, but the MAWD and RRC2 are inexpensive and just plain work. The others tend to have more features, but also cost more because of it, and are typically also more difficult to configure because of it.

-Kevin

[RandyT0001]

Just for quick comparison (I've been looking at various altimeters also over the past few weeks) here's a brief paragraph about each one mentioned so far.

The Adept ALTS2 Altimeter has a battery mounted on it circuit board directly and includes 24'" long CAB leads for deployment charges (like to the bottom of the airframe tube where motor ejection normally occurs). It has limited choices on main parachute deployment of either 750ft or 250ft AGL. It uses a barometric sensor and in is basic version is limited to 15k ft MSL (so if you fly in CO someday you might be limited to 10k AGL flights). It does not log any flight parameters. For about 10% more price you can get the altimeter usable up to 50k ft MSL. It is 4.5" long by 0.9” wide by 0.65” thick and weighs 0.9 ounces (including battery).

The RRC2 mini altimeter by Missileworks is smaller at 1" wide by 3.15" long (by 0.5"? thick) but does not have a battery mounted on the circuit board, the use has to buy a seperate battery cable/clip to secure the battery to the altimeter 'sled'. It uses compression screw terminals so normal solid wires for deployment charges can be used. It use a barometric sensor and is calibrated up to 40k ft MSL. The main deployment can be adjusted in 100' increments from 300' to 3000' AGL. Both the apogee drogue and main have additional time delay options if the unit is used as a backup for other altimeters (such as is used in L3 rockets). To use some features it has to be programmed by operator and it logs four flight parameters. It weighs 0.6 oz (W/O battery).

The MAWD by PerfectFlite is 3.0” long by 0.9” wide by 0.7” thick, weighs 0.7 oz, that also uses compression screw terminals for deplymnet charge hookup and the unit external power switch (like the RRC2). Like the RRC2 the battery must be secured by the operator by a seperate clip onto the 'sled'. It is calibrated up to 25k ft MSL. It's main parachute is adjustable from 300' to 1700' in 200' increments by the use of DIP switches which is easier than the programming of the RRC2. It is also a logging altimeter that requires a seperately purchased cable to d/l data to a computer.

Featherweight's Raven altimeter is the smallest of the four at 1.8" long by 0.8" wide by 0.47" thick and the lightest at 0.24 oz. (W/O battery). As with the previous two the battery is not mounted on the board so the user must secure the battery to the 'sled' and connect it to the altimeter. The Raven is an accelerometer based unit with a barametric sensor backup (up to 100k ft MSL). It uses compression screw terminals and has four outputs (vs two for the other three altimeters). The unit has multiple adjustments to it's four outputs that requires a computer link (using seperate user supplied mini USB cable) for programing (unlike other altimeters above that use onboard switches to program). It logs flight data.

[Adrian A]

Featherweight's Raven altimeter is the smallest of the four at 1.8" long by 0.8" wide (by 0.7"? thick) and the lightest at 0.24 oz. (W/O battery). As with the previous two the battery is not mounted on the board (an option to mount small A23 batteries exists for higher price). The Raven is an accelerometer based unit with a barametric sensor backup (up to 100k ft MSL). It uses compression screw terminals and has four outputs (vs two for the other three altimeters). The unit has multiple adjustments to it's four outputs that requires a computer link (using seperate user supplied mini USB cable) for programing (unlike other altimeters above that use onboard switches to program). It logs flight data.

Thanks for the summary, Randy. A couple of clarifications:
The height of the Raven 0.47". It fits easily into 24mm tubes or larger.

The A23 version is sold out and will not be put back into production. However, there will soon be av-bay kits available that include a li-polymer battery, battery charger, and magnetically-activated arm switch. The 38mm version of the av-bay kit should be available within a couple of weeks. The kit allows a complete av-bay installation without requiring any wiring.

The Raven can be flown without ever hooking it up to a computer, since the default output settings will work for almost any dual-deploy application. Changing the deployment output settings is done via the Featherweight Interface Program (FIP) graphical user interface. Using the FIP, you can also perform a realistic simulated flight test of your av-bay setup, and see graphs of recorded data, either from a ground test or flight test.

[Zeus-cat]

I have the Perfectflite MAWD (dual deploy) and Perfectflite Alt15K Rev 2 (logging only, logs 3 flights). I can tell you that if you like playing with data you should seriously consider an altimeter that logs data as well as being dual deploy capable.

I have attached Excel files showing the output of both altimeters. The MAWD data clearly shows the rapid descent from apogee until the main chute fully depolys at 200 feet (main was set for 300, but the rocket drops another 100 feet before the chute fully opens).

[Zeus-cat]

The A23 version is sold out and will not be put back into production. However, there will soon be av-bay kits available that include a li-polymer battery, battery charger, and magnetically-activated arm switch. The 38mm version of the av-bay kit should be available within a couple of weeks. The kit allows a complete av-bay installation without requiring any wiring.

I know I'll be checking that out!

[NjCo]

For altimeters that have a link to a computer, is this generally through a USB cable? And for these altimeters I would assume you need some sort of program running on the computer to deal with setting options on the altimeter and dealing with data downloaded from the altimeter (for those that record data). Are there any recording altimeters that will work on a Mac? Looks like what we need is a giant chart to compare all of the features for all of the altimeters out there. There are a lot of options to sort through.

[RandyT0001]

For altimeters that have a link to a computer, is this generally through a USB cable? And for these altimeters I would assume you need some sort of program running on the computer to deal with setting options on the altimeter and dealing with data downloaded from the altimeter (for those that record data). Are there any recording altimeters that will work on a Mac? Looks like what we need is a giant chart to compare all of the features for all of the altimeters out there. There are a lot of options to sort through.

Generally done through a USB or mini USB cable (some older ones still use serial port connections). The logging altimeters come with software to run on the computer for d/l. Of the four listed here only the Raven requires a computer for adjustments to outputs (factory pre-sets allow for the use as a dual deployment with apogee deploy and main at 700' AGL w/o computer hookup). The PerfectFlite MAWD has a seperate computer d/l cable for serial port interface with a Mac for sale. A little bit of research in the Rocketry Electronics section of the Research thread here on TRF let's one compare products.

[rocket999]

I haven't had much experience with other altimeters, but I really like the Perfectflight MAWD. Great for rockets in that diameter.

Sam

[BsSmith]

I've used a Featherweight Parrot and a Perfectflite MAWD. Both have their ups and downs.

The MAWD is simple to use and the mach delay and main deployment settings can be easily changed at the field. However, it can't be used near transitions or in a nose cone. It also can't hold more that one log at a time, which is a problem for me because I like logs.

The Parrot is a great little altimeter that can fit in pretty much anything you want it to, and the logs and interface programs are great. It can hold up to five flight logs at a time. My only complaints are that you can't change the settings at the field without a laptop, and you have to take apart the av bay to turn on the altimeter. I haven't had any experience with the Raven yet (I just ordered one yesterday), but it looks like it may be the same. If the altimeter battery is externally mounted, it may be possible to run a switch to that.

[troj]

The Parrot is a great little altimeter that can fit in pretty much anything you want it to, and the logs and interface programs are great. It can hold up to five flight logs at a time. My only complaints are that you can't change the settings at the field without a laptop, and you have to take apart the av bay to turn on the altimeter. I haven't had any experience with the Raven yet (I just ordered one yesterday), but it looks like it may be the same. If the altimeter battery is externally mounted, it may be possible to run a switch to that.

I'd agree with most of what you said, but regarding "you have to take apart the av bay to turn on the altimeter" is a function of av bay design, not the altimeter itself.

-Kevin

[BsSmith]

I'd agree with most of what you said, but regarding "you have to take apart the av bay to turn on the altimeter" is a function of av bay design, not the altimeter itself.

-Kevin

The main power switch and arming switch for the altimeter are screw switches mounted to the altimeter board itself. So, you'd either need to take apart the bay to turn those switches or you'd need to have a port that you can put a screwdriver through to turn them. Once the altimeter is on and beeping, you can fully arm it with an external switch on the pad.

[cjl]

The main power switch and arming switch for the altimeter is a screw switch mounted to the altimeter itself. So, you'd either need to take apart the bay to turn those switches or you'd need to have a port that you can put a screwdriver through to turn them. Once the altimeter is on and beeping, you can fully arm it with an external switch on the pad.

That's not true with the Raven, just so you know.

[BsSmith]

That's not true with the Raven, just so you know.

That's great!

My only real complaint with the Parrot was that. Not being able to change the settings at the field is fine, I've never had to do it, but the switches mounted on the board was a little bit of a hassle.

I'm really glad to see that.

[Handeman]

For a very reliable easy to use altimeter, the Perfectflite HiAlt45 is hard to beat. It does not record data. It only uses one battery. It does have high current outputs so it'll fire any ematch.

I've had the HiAlt45 for three years now. It's performed perfectly including several 80+G flights on Warp 9 motors, has never failed to fire a charge, whether its a commercial ematch or homemade ematches, or Xmas tree bulb charges. I made several batches of home made ematches and the HiAlt45 fire over two dozen on the same battery without fail. Another batch of ematches used with a MAWD, only fired half of the ematches because of the lower peak output current of the MAWD.

If you only need the peak altitude and dependable dual deploy at a good price, I know the HiAlt45 is a good choice.
I can't talk about the altimeters I haven't used.

[stickershock23]

Some great stuff in this thread.

Personal choice? I have NEVER had a problem with a MAWD or HI ALT 45. for the price they are very nice. and just plain work. and are easy to use. buy thema little on the simple side. but if you don't need all the bells and whistles why

I Just bought 2 ravens.. I have not flown them. but I will say they are a little more expensive, but WELL worth the expense. the big thing is they record 5 flights. (were the MAWD does 1) and they are computer interfaced and programmable. I just got playing with mine, and with the support offered by Featherweight, its pretty easy to program.

I am very impressed so far with the raven... Oh its its friggin tiny!

[troj]

The main power switch and arming switch for the altimeter are screw switches mounted to the altimeter board itself. So, you'd either need to take apart the bay to turn those switches or you'd need to have a port that you can put a screwdriver through to turn them. Once the altimeter is on and beeping, you can fully arm it with an external switch on the pad.

Yep, I have a pair of them. It's no different than the AltAcc, which was also armed via a screw switch on the board.

...and that's the default configuration. When I purchased mine, I had the option for having the screw switch on the board, or not.

It's also possible to clip the wires to the battery (or desolder one of them) and put a remote switch in place.

Even with the stock configuration that mine came with, it's a function of how the bay is designed. I can easily place a hole such that I can power on the altimeter without disassembling anything.

-Kevin

[brianc]

The main power switch and arming switch for the altimeter are screw switches mounted to the altimeter board itself. So, you'd either need to take apart the bay to turn those switches or you'd need to have a port that you can put a screwdriver through to turn them. Once the altimeter is on and beeping, you can fully arm it with an external switch on the pad.

You can also add an external power switch to the Parrot.

I described how I did it in this thread on the Featherweight site.
http://myforum.featherweightaltimete...aspx?id=142505

[Handeman]

Some great stuff in this thread.

I Just bought 2 ravens.. I have not flown them. but I will say they are a little more expensive, but WELL worth the expense. the big thing is they record 5 flights. (were the MAWD does 1) and they are computer interfaced and programmable. I just got playing with mine, and with the support offered by Featherweight, its pretty easy to program.

I haven't been looking for another altimeter in a while. When the raven is programmed, do you have to use the computer interface? I would want to use it in several rockets and don't want to have to drag a laptop out to the site to re-program an altimeter just to switch rockets.

[BsSmith]

I haven't been looking for another altimeter in a while. When the raven is programmed, do you have to use the computer interface? I would want to use it in several rockets and don't want to have to drag a laptop out to the site to re-program an altimeter just to switch rockets.

I'm pretty sure that it can only be programmed with a computer. That being said, it has four output channels that can each be programmed to a different setting. If you have different needs for two different rockets, just program them into the altimeter so it can be used for both.

[cjl]

I haven't been looking for another altimeter in a while. When the raven is programmed, do you have to use the computer interface? I would want to use it in several rockets and don't want to have to drag a laptop out to the site to re-program an altimeter just to switch rockets.

It requires a computer to reprogram, but I don't see why you would need to. A single program should work quite well for many rockets.

[Adrian A]

I'm pretty sure that it can only be programmed with a computer. That being said, it has four output channels that can each be programmed to a different setting. If you have different needs for two different rockets, just program them into the altimeter so it can be used for both.

Since the mach inhibit is automatic based on the in-flight measured velocity, there is no need to ever set a Mach delay. That leaves the main deployment altitude as something you might want to change between rockets.

There is one selectable AGL<value that can be used for main deployment on any of the channels, but it's a single value for the altimeter. So if you can pick a main deployment altitude that would work for all your rockets, you wouldn't need to ever change the deployment settings to move it from one rocket to another.

[bsexton]

I've been very happy with my Missile Works RRC2 altimeters (I have 3 of them) particularly the latest RRC2 Mini.

[karlbaum]

I love my Featherweight Raven. It does everything I want. But if you don't want data recording the Transolve P6-k is a workhorse. It fires my charges every time with no problems.