Altimeter Suggestion

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Moldie

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Howdy all,

I recently aquired a LOC Fantom (4") with the LOC E-Bay.
http://shop.rocketsbymelissa.com/pr...78AE.qscstrfrnt03?categoryId=15&productId=124

I am planning on making this my first dual deploy attempt. I am deciding between the Missileworks RRC2-mini Altimeter
http://www.missileworks.com/mm5/mer...C&Product_Code=RRC2-mini&Category_Code=cat050

and the Perfectflite miniAlt/WD logging dual event altimeter
http://68.178.208.82/cgi/PF_Store/perlshop.cgi?ACTION=thispage&thispage=MAWD.html&ORDER_ID=222284032

I am leaning towards the Missile Works but don't have any experience with either. And on a secondary note, the Perfectflite Ejection Charge Kits seem pretty solid. Any suggestions would be great.

Thanks.
 

Viperfixr

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It's a simpler, first altimeter, and it's reliability is tops. It also has a download capability that the RRC2 doesn't have. I don't have a MW RRC2, but I steered away from it for my first DD altimeter because the setup is more complex without the DIP switches (which are very easy).
 

lmt56

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Simple
Get one of each.
Always good to have a backup when dual deploy.
 

DMcCauley

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I would get the Perfectflite MAWD. Out of all the altimeters i've used, and i have had about all of them (Ozark, GWiz, RRC, Perfectflite), i like the MAWD the best and it has been the most reliable. ARTS2 is good too, but it has a few more bells and whistles.
 

RCBrust

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I've also been trying to decide between the MAWD and the RRC2. I was pretty well set on the MAWD until I thought I read somewhere that it has limited output current capability.

Does anyone have any more information regarding this or further comment?

Thanks,
Randy
 

DMcCauley

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The MAWD has more than enough current capability for even several ematches in parallel.

Never had an ematch that failed to light yet.
 

RCBrust

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Which e-match brand(s) have you used with it?

Thanks,
Randy
 

blackjack2564

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I have the RRC2 mini...Perfectflite Mawd and HiAlt 45.
Keep in mind that the Mawd also requires the data download kit costing an extra 30.00. Taking the total cost to 130.00.

If it were me, just starting out again, I 'd rather have 2 altimeters for an extra 30.00 2x80 =160 than just one for 130.00

The HiAlt is 80.00 as well as the Mini.

I have used all 3 with. Oraxels, davey fire's, J-tek and M-tek. and even the mini xmas tree lite bulbs. They have all worked fine and supplied the needed power to fire.

More important to the first time user, is to find out what some of your flying buddies use. That way they can help you out over the "first time jitters" at your launches.

All 3 units mentioned are very high quality,quite small and will take a lot of abuse .
 

troj

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I've owned an AltAcc, RDAS, RRC2, RRC2 Mini, MAWD and a G-Wiz LC Deluxe.

Of those, my RRC2 Mini and MAWD are my favorites. Simple, easy to use, and they just work.

FWIW, our big projects fly with a pair of MAWDs running the critical recovery events. We've never had a problem with them. I'd have no qualms about putting the RRC2s in the same role, although our driver boards are designed specifically for the MAWD's output (we fire 16 matches based on the output of 2 MAWDs).

-Kevin
 

Moldie

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Thanks for all the great info. It has been very helpful. It looks like the Perfectflite will be the winner. When I pull the trigger and make the purchase, I will let ya'll know.

Thanks again,
Moldie
 
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RCBrust

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RRC2 Mini users,

Can this unit run through a momentary lapse of power like the MAWD can? Just went to check the MissileWorks website to see if it's mentioned there but it's down temporarily.

Thanks,
Randy
 

troj

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RRC2 Mini users,

Can this unit run through a momentary lapse of power like the MAWD can? Just went to check the MissileWorks website to see if it's mentioned there but it's down temporarily.
I don't know the answer, although it does make me wonder why you're asking it?

The idea of planning around an altimeter losing power, and hoping it comes back up properly just kinda scares me.

-Kevin
 

hognutz63

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RRC2 Mini users,

Can this unit run through a momentary lapse of power like the MAWD can? Just went to check the MissileWorks website to see if it's mentioned there but it's down temporarily.
I don't know the answer either, but Jim Amos has always answered any questions I have emailed him in a very timely manner.
 

DMcCauley

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I don't know the answer, although it does make me wonder why you're asking it?

The idea of planning around an altimeter losing power, and hoping it comes back up properly just kinda scares me.

-Kevin
Not sure why this scares you. Its certaintly is a condition in which you want your electronics to protect against - caused by either a transient break in electrical contacts in a switch, battery connector, wire, etc...

If done properly, your altimeter never loses power during these "glitches." A small capacitor isolated at the input of the uProc will be sized to maintain the proper voltage during these glitches for some specified period of time.

You certaintly don't want your altimeter to lose power and reset for a transient glitch due to a bounching contact, or something on a switch or your battery connector.
 

RCBrust

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Not sure why this scares you. Its certaintly is a condition in which you want your electronics to protect against - caused by either a transient break in electrical contacts in a switch, battery connector, wire, etc...

If done properly, your altimeter never loses power during these "glitches." A small capacitor isolated at the input of the uProc will be sized to maintain the proper voltage during these glitches for some specified period of time.

You certaintly don't want your altimeter to lose power and reset for a transient glitch due to a bounching contact, or something on a switch or your battery connector.
Bingo.
 

troj

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Not sure why this scares you. Its certaintly is a condition in which you want your electronics to protect against - caused by either a transient break in electrical contacts in a switch, battery connector, wire, etc...

If done properly, your altimeter never loses power during these "glitches." A small capacitor isolated at the input of the uProc will be sized to maintain the proper voltage during these glitches for some specified period of time.

You certaintly don't want your altimeter to lose power and reset for a transient glitch due to a bounching contact, or something on a switch or your battery connector.
It scares me because it can easily lead to sloppy construction by people who see such an idea, and assume it's okay, "because the altimeter can handle a power glitch."

I'd much rather design wiring and recovery such that I assume the altimeter can't take it, and I have to provide a constant, reliable power source, or my rocket will be toast.

-Kevin
 

RCBrust

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I'd much rather design wiring and recovery such that I assume the altimeter can't take it, and I have to provide a constant, reliable power source, or my rocket will be toast.
Agree 100%. And then I like to add the ability of the altimeter to withstand power glitches on top of that.

Randy
 

DMcCauley

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It scares me because it can easily lead to sloppy construction by people who see such an idea, and assume it's okay, "because the altimeter can handle a power glitch."

I'd much rather design wiring and recovery such that I assume the altimeter can't take it, and I have to provide a constant, reliable power source, or my rocket will be toast.

-Kevin
No. What it does is simply add another layer of protection. I don't care who you are, what your background is, and how many systems you've built, there is always the possibility that you'll have an intermittent connection, regardless of what steps you take to avoid it.

Having an altimeter to withstand such a "glitch" or whatever you want to call it is just good design practice and common sense. No, its not a substitute for good wiring practices, but as i said before, its another layer of protection.

As a professional power systems engineer, i've worked on everything from shipboard radar to planetary space probe power systems. Every design i've worked on has a similar requirement regarding intermittant loss of power for the very same reasons.

So again, is it scary someone is asking about this? Absolutely not. In fact, it shows me this guy is actually doing some thinking into the possible failure modes a recovery system might see and is simply inquiring about how the electronics being used within that system might deal with a power glitch of some type.
 

DMcCauley

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I don't know the answer, although it does make me wonder why you're asking it?

The idea of planning around an altimeter losing power, and hoping it comes back up properly just kinda scares me.

-Kevin
Also, the reason this guy is probably asking the question is simply to compare altimeters and find any discriminators which may help him in his final decision.

If altimeter A does everything altimeter B does, but also can handle a 1 second power glitch, than obviously thats a major discriminator and you would want to go with altimeter A for that extra layer of protection.

No one ever said this guy was planning on purposely losing power to an altimeter. Thats a bit silly, don't you think?
 

troj

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So again, is it scary someone is asking about this? Absolutely not. In fact, it shows me this guy is actually doing some thinking into the possible failure modes a recovery system might see and is simply inquiring about how the electronics being used within that system might deal with a power glitch of some type.
Sorry, but I disagree.

Why?

Because while some folks will understand to not rely on the altimeter handling it, there are those who will take the "eh, I can be sloppy, because the altimeter can handle a power glitch" attitude.

There's an altimeter out there that's known for having two batteries be strongly recommended. Yet there are people who fly it with one, "because it's always worked for me that way."

-Kevin
 

DMcCauley

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Sorry, but I disagree.

Why?

Because while some folks will understand to not rely on the altimeter handling it, there are those who will take the "eh, I can be sloppy, because the altimeter can handle a power glitch" attitude.

-Kevin
Thats ridiculous. I challenge you to find one person out there who has purposedly went out of their way to make their wiring "sloppy" because of the fact an altitmeter can handle a power glitch.

Thats like someone asking if Rocket ABC can survive a ballistic landing and then not using any sort of recovery system period.
 

NJnike

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I don't think someone wanting to make sure their bases are covered will promote sloppy work. From my experiences I've learned that anyone who does sloppy work does so habitually and there's little that's going to change that. Whether they have a fool-proof system or one that's a little iffy, they're going to put the same amount of effort and attention into whatever they're building. I've seen folks at launches that I outright told "there's a big crack down the side of your rocket so I wouldn't fly that if I were you" and they thanked me for the heads-up. 15 minutes later that rocket was in several pieces when they ignored me and flew it anyway. People are gonna do what they're gonna do.
 

DMcCauley

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I don't think someone wanting to make sure their bases are covered will promote sloppy work. From my experiences I've learned that anyone who does sloppy work does so habitually and there's little that's going to change that. Whether they have a fool-proof system or one that's a little iffy, they're going to put the same amount of effort and attention into whatever they're building. I've seen folks at launches that I outright told "there's a big crack down the side of your rocket so I wouldn't fly that if I were you" and they thanked me for the heads-up. 15 minutes later that rocket was in several pieces when they ignored me and flew it anyway. People are gonna do what they're gonna do.
Nicely said Randy.
As my point was, the power protection is merely another layer of protection to the recovery system.

BTW, i'll make sure i repair that big crack! :D
 
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