Missile Works "Cyber Monday" Sale - 11/28/2016 - 9AM to 9PM MST

MWC

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I'd expect TRA might give consideration to its use for record attempts if an appropriate petition is made. Kurt

I've kept the records committee in the loop, and we've met all their requirements for compliance. Now that we're releasing this system for sale, they'll be updating their web page and listing the RTx/GPS System as an option.

https://www.tripoli.org/Records/Approved-GPS
 

jd2cylman

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Jim,

Can you give me the "cave man" difference between the standard RTx and the Navigator RTx again? I think the Navigator is the one I want, but don't recall...

Adrian
 

MWC

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Jim,

Can you give me the "cave man" difference between the standard RTx and the Navigator RTx again? I think the Navigator is the one I want, but don't recall...

Adrian


Gort make fire!

The Navigator Base unit has a GPS module allowing it compute an autonomous navigational solution to the Rocket unit for display on the optional LCD (Heading, Distance and ETA). Standard systems rely on secondary GPS enabled devices, usually a handheld GPS or an Android "Rocket" app. One can manually transpose Lat/Lon from the optional LCD to a secondary GPS enabled device or send Lat/Lon coordinates via optional Bluetooth to your "Rocket" app.

And you'll need to choose you "Rocket" antenna style and GPS module mounting preference too.
 

jd2cylman

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Gort make fire! :tongue:

The Navigator Base unit has a GPS module allowing it compute an autonomous navigational solution to the Rocket unit for display on the optional LCD (Heading, Distance and ETA). Standard systems rely on secondary GPS enabled devices, usually a handheld GPS or an Android "Rocket" app. One can manually transpose Lat/Lon from the optional LCD to a secondary GPS enabled device or send Lat/Lon coordinates via optional Bluetooth to your "Rocket" app.

And you'll need to choose you "Rocket" antenna style and GPS module mounting preference too.

OK, Thanks!!! Yep, Navigator it is for me... I think you said the wire whip will be sufficient for most "standard" flights, but I don't remember what was suggested about the GPS mount for mere mortals like me who like to keep the rocket in the same county...

Adrian
 

ColumbiaNX01

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Which is the better antenna choice? The whip antenna or the jack for a screw on antenna? If I want to use the the GPS on a 3d printed sled that missile works sells I need to get the edge mount?
 

ksaves2

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Gort make fire!

The Navigator Base unit has a GPS module allowing it compute an autonomous navigational solution to the Rocket unit for display on the optional LCD (Heading, Distance and ETA). Standard systems rely on secondary GPS enabled devices, usually a handheld GPS or an Android "Rocket" app. One can manually transpose Lat/Lon from the optional LCD to a secondary GPS enabled device or send Lat/Lon coordinates via optional Bluetooth to your "Rocket" app.

And you'll need to choose you "Rocket" antenna style and GPS module mounting preference too.

Ew Kay, What would be a full system with the RTx tracker, LCD Navigator/Receiver with B/T capability, computer interface to off load the position data on the tracker to a computer and the proper case for the receiver? (I think it's the $34.95 one)

Kurt
 

ksaves2

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OK, Thanks!!! Yep, Navigator it is for me... I think you said the wire whip will be sufficient for most "standard" flights, but I don't remember what was suggested about the GPS mount for mere mortals like me who like to keep the rocket in the same county...

Adrian

If the whip is inside a metallic painted rocket one could have a range problem. With RP-SMA, might be a space issue if bay size is limited and one wants the antenna completely inside the bay. On the other hand, there are a variety of interconnect cables that can be found that can be screwed into an RP-SMA socket with a bulkhead mount on the end that can be on an aft facing bulkhead that is exposed at apogee deployment: https://www.ebay.com/itm/4-RP-SMA-F...607419?hash=item1a071ec7bb:g:bZ0AAOSwd0BV7CdD

If one wants the best range, the optimal antenna is deployment in "free air". If ones electronics bay or nosecone mounting situation is radio lucent that would work also. What one should try to avoid is the antenna paralleling any metal or all-thread.
That includes 9V batteries on the other side of the sled directly behind the antenna (wire or otherwise).

Now the very erudite out there are going to be posting, "I've flown the RTx folded back along itself, paralleling metal all-thread just fine. You're full of baloney." Well remember, more Rf horsepower can overcome a less than optimal setup.
Sure if ones rocket doesn't end up very far away, it may work but I will bet an optimally setup transmitting antenna (and receive station antenna for that matter) will trump the range that can be had when one violates the rules of an
antenna in free space. Ones mileage will vary. Kurt
 

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In addition to a couple of RRC3 altimeters, I was planning to pick up a couple of sleds, but I just realized the distance between all thread rods on my new Binder design Excel kit is 2 1/4" I don't see a sled that fits. Am I out of luck as far as 3D printed sleds go?
 
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Buckeye

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You can drill new holes in the bulkheads for threaded rod that corresponds to the sled dimensions. Plug up the old holes with epoxy.
 

jd2cylman

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OK,
Kurt's talked me into the RPSMA jack. It looks like Jim has an antenna with a cable that I can just bolt through the aft bulkhead of my AV bay. Now edge or flush. Edge is better I think I recall.

Adrian
 
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calambert

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You can drill new holes in the bulkheads for threaded rod that corresponds to the sled dimensions. Plug up the old holes with epoxy.

Thanks, I was thinking of drilling new holes, but had not thought of filling the old ones with epoxy. That should do it. It just took me by surprise when I noticed there wasn't a sled that fit.
 

dshmel

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Ew Kay, What would be a full system with the RTx tracker, LCD Navigator/Receiver with B/T capability, computer interface to off load the position data on the tracker to a computer and the proper case for the receiver? (I think it's the $34.95 one)

Kurt

I had the same question, what would be a complete turn key system? I would want the transmitter, receiver, case, etc. Everything except the batteries.
 

ksaves2

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OK,
Kurt's talked me into the RPSMA jack. It looks like Jim has an antenna with a cable that I can just bolt through the aft bulkhead of my AV bay. Now edge or flush. Edge is better I think I recall.

Adrian

I don't know if there is that much difference in real use. First of all, under acceleration the GPS can lose lock because of Doppler effects of the received signal. I thank Keith Packard for pointing that out in a post on TRF. Plus if one looks at
the G limits of the commercial GPS receiver chipsets, most of them are only guaranteed to 4G's acceleration. Doesn't mean they break it means they might break lock momentarily. In addition there is a 1000 knot/ 1200mph speed limit
so a commercial GPS can't be used for a guided rocket with nefarious purposes in mind. Your mach screamer might not get a lock temporarily due to the above phenomena.

Once in the coast phase of the boost, an upward facing GPS has a clear overall shot of the sky. A side facing one still has a good shot of the horizon but whether or not high frequency spinning makes a difference for amateur rocketry purposes
I don't know.

If one gets an upward facing GPS antenna, might be able to get a lock some time before apogee and on descent here's where it may get tricky. If the upward facing antenna is lying horizontally on descent facing the horizon, that still is a pretty good position to get and keep a fair number of satellites locked. If ones descent has the GPS antenna facing the ground, that would be less optimal. Will the GPS keep lock? Maybe and likely but there's a better chance if it were facing the horizon or up to the sky. That's where technically a side facing antenna might have an edge. But then again, both configurations are going to be flopping around on descent anyways. I think that's the reason some Rf positions are missed on descent at the
receiver. Please note, with onboard memory recording the GPS positions written to memory one can miss a bunch of Rf packets but the GPS may still have a lock and dutifully writing the positions to memory for later download.
Found that out when a metallic painted rocket couldn't get the Rf out of the airframe but the Rf attenuation did NOT extend to the GPS receiver. When I belatedly did a download attempt of the Beeline GPS .kml memory file, every darned position was recorded once a second with a 7 to 11 satellite lock!! I was lucky the rocket recovered within sight.

Once the rocket has landed, the side facing GPS antenna might be facing down, up or either side. Now I've taken a Sainsonic AP510 laid it sideways and it keeps a lock pretty well. It has an upward facing GPS antenna so it was
facing sideways for the test. An upward facing GPS antenna of a RTx as opposed to a side mounted one like I've just mentioned will be pointed sideways on the ground unless the nosecone containing a RTx "sticks" the landing and is pointed down. Of course the upward facing GPS receive antenna will be facing sidways over the ground if in a mid-section mounted ebay.

In the reality of amateur rocketry, I don't know if there is that much difference between the two configurations as there are so many variables involved. If one has an idea as to the configuration of their dual deploy rocket as it descends, one configuration might be "better" than another but is it accuracy to the point of absurdity? I don't know. The only way to find out would be to fly two RTx units of upward and side facing GPS antennas in the same
rocket, multiple times and see if it makes a difference. I've flown all my GPS trackers with side mounted antennas and got the rockets back every time except the one that crashed.

My gut feeling me thinks when it comes to "finding the rocket" either configuration will work equally the same. Any comments from anyone better informed on this subject? I'm open to learning if what I mention above is inaccurate
and can be changed. Kurt
 

woferry

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I've flown a bunch of Eggtimer GPS units (I own about a half-dozen EF TX's and a few ET TRS's), but I'm interested in giving the RTX a shot, especially for an upcoming 2-stage rocket where I'd like to run two GPS trackers at the same time so I could use one Eggfinder and one RTX.

The setup I like to run with my Eggfinders is one transmitter and two receivers, one of the receivers is handheld (EF LCD) and the other is back at 'camp' with my laptop (EF RX), recording all of the data. I guess it sounds like the RTX does its own logging, so I can skip the laptop connection and just download the information post-flight? Is the recording done on the part that flies, or the base unit, i.e. if the unthinkable happens and the rocket crashes, is the log gone or is it captured by the receiver?

What I can't really figure out is what are all of the pieces I need to have a fully-working system, ideally including an RRC3 connection since it seems then the RTX can transmit the altimeter information as well(??). I looked over the RTX User Manual and it really didn't help me to understand the different pieces involved. I've never owned any Missile Works electronics, so I'm not sure what would be needed to make the RRC3 go either, can the same LCD screen work with the RRC3 as well as the RTX?

In short, can anyone who understands all of the Missile Works pieces provide a 'shopping list' that I could use for tomorrow's sale? It would be greatly appreciated. To summarize, my requirements are:

1) GPS tracker in the rocket (duh)
2) Handheld unit to report GPS information and take while searching for the rocket
3) Ability to download GPS tracks to a computer (post-flight, or during flight if it isn't recorded)
With a nice-to-have of:
4) Ability to live downlink data from on-board RRC3 (? - I think it works this way)
Actually, #4 suggests I might like to have the data recorded on my computer live rather than downloaded later (seems like someone could do a Kate-like thing with this?), so knowing what extra hardware would be necessary to set up a second receiver connected to a computer would be nice. Computer in my case means a Mac if that matters.

Thanks in advance.
 

MWC

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OK, Thanks!!! Yep, Navigator it is for me... I think you said the wire whip will be sufficient for most "standard" flights, but I don't remember what was suggested about the GPS mount for mere mortals like me who like to keep the rocket in the same county...

Adrian

The wire-whip should be sufficient and it's certainly an easier install, especially if you plan on sending this up in multiple projects. Wire whips also work especially well for nosecone installs.

As far as the GPS module orientation goes, it's a matter of choice. There's a more optimal constellation with the edge mount, but it's downside is the hassle of mounting. It won't sit flush on a traditional sled, but it can bolt on directly to the 3D PLA sleds we sell (since the edge mounts sits "off the edge" of the sled).

As a note to all, ONLY the edge mount version mounts directly on our 3D PLA sleds with the GPS module hanging over the edge. You'll need additional coupler space for the module to sit behind your bulkhead.
 

MWC

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In addition to a couple of RRC3 altimeters, I was planning to pick up a couple of sleds, but I just realized the distance between all thread rods on my new Binder design Excel kit is 2 1/4" I don't see a sled that fits. Am I out of luck as far as 3D printed sleds go?

All-thread spacing is not standardized, so as suggested you can plug/re-drill or create new bulkheads. I've listed the all-thread centers and sizes for each sled model in the product detail pages for each sled.
 

MWC

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Ew Kay, What would be a full system with the RTx tracker, LCD Navigator/Receiver with B/T capability, computer interface to off load the position data on the tracker to a computer and the proper case for the receiver? (I think it's the $34.95 one)

Kurt

- Navigator $260
- BTMM module (x2) $20
- 3D PLA RTx case kit ~$32
- LCD Module $40
- LCD 3D PLA ~$15

You'd need to choose your antenna option (whip or jack) and GPS mount (flush or edge), so give or take a few bucks.

One "could" take the BTMM module out of the base RTx handheld to "upload" flash recordings from your "rocket" RTx, but for an extra $10 you could have a Bluetooth linked dedicated for post-flight uploads to your PC.
 

tim cubbedge

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This is what I bought as a beta tester:
LCD terminal
RTx/GPS navigator system (flush mount with whip antenna)
3D printed LCD case
3D printed Rtx case

As Jim said, you also need batteries. I'm using 450mA 2S Lipo in transmitters and a 300mA 2S lipo in reciever.

That's it if you want a standalone unit that will walk you to your rocket every time. I don't use Bluetooth or any computers or any other handheld device in the field. I download all data later. It's simple and worth its price and I'm buying a second transmitter tomorrow.
 

MWC

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The setup I like to run with my Eggfinders is one transmitter and two receivers, one of the receivers is handheld (EF LCD) and the other is back at 'camp' with my laptop (EF RX), recording all of the data. I guess it sounds like the RTX does its own logging, so I can skip the laptop connection and just download the information post-flight? Is the recording done on the part that flies, or the base unit, i.e. if the unthinkable happens and the rocket crashes, is the log gone or is it captured by the receiver?

Correct, Will. The "Rocket" unit will persist all the GPS data to it's local flash memory for post flight upload (7 slots of 68 minutes each). If you crash your project or it never comes back that data could be lost. The radios use a "many-to-one" network scheme, so you could "stream" the Base unit data output to a PC app (like uCenter for example), and once you've landed, disconnect and take the base unit to assist in recovery. You could have a USB-IO link or a Bluetooth link to you PC, but it's an exclusive link (one paired device at a time).

What I can't really figure out is what are all of the pieces I need to have a fully-working system, ideally including an RRC3 connection since it seems then the RTX can transmit the altimeter information as well(??). I looked over the RTX User Manual and it really didn't help me to understand the different pieces involved. I've never owned any Missile Works electronics, so I'm not sure what would be needed to make the RRC3 go either, can the same LCD screen work with the RRC3 as well as the RTX?

It's a double-edged sword having all the configurable options, but that's how I roll... It places the onus on the end-user to determine the best collection of parts and pieces. Maybe you already own an LCD or USB module, maybe you want a spare device, mayber you want all wireless Bluetooth interfacing, PC or Android endpoints, or you want to use your trusty Garmin or Magellan handheld...

I made a list for Kurt S. above that lists all the major parts... barring an interface cable between the RRC3 altimeter and RTx, it's everything you need. Also relaize that you can change capabilities on the fly... LCD, Bluetooth, USB, RRC3 tether, etc.

The RRC3 plugs and plays with all the same modules (BTMM, LCDT, USB-IO), so it really comes down to your preference, project needs and budget. Get exclusive endpoints for all your toys, or you can share modules as your budget and fuss-factor allow.


To summarize, my requirements are:

1) GPS tracker in the rocket (duh)
2) Handheld unit to report GPS information and take while searching for the rocket
3) Ability to download GPS tracks to a computer (post-flight, or during flight if it isn't recorded)
With a nice-to-have of:
4) Ability to live downlink data from on-board RRC3 (? - I think it works this way)
Actually, #4 suggests I might like to have the data recorded on my computer live rather than downloaded later (seems like someone could do a Kate-like thing with this?), so knowing what extra hardware would be necessary to set up a second receiver connected to a computer would be nice. Computer in my case means a Mac if that matters.

Thanks in advance.

I'd suggest the same collection as I did for Kurt, then add an optional RRC3 and tether cable if you want. The "Kate/Telemetrum" talking is coming as I'm going to start on a multi-platform app that will fuse RRC3/RTx data into a single HUD. I've even got a volunteer to assist with collaborating on the app development.
 

MWC

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"Cyber Savings" #5 / Final Update

We've expanded the Cyber Sale to the following items for additional $avings:

- LCD Modules
- USB IO Modules
- PET2+ Timers
- 6/32 Screw Switches

Also, spend $100 or more during our Cyber Monday Sale and receive FREE SHIPPING with a $7 discount at Checkout
 

claytonbirchenough

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This is what I bought as a beta tester:
LCD terminal
RTx/GPS navigator system (flush mount with whip antenna)
3D printed LCD case
3D printed Rtx case

As Jim said, you also need batteries. I'm using 450mA 2S Lipo in transmitters and a 300mA 2S lipo in reciever.

That's it if you want a standalone unit that will walk you to your rocket every time. I don't use Bluetooth or any computers or any other handheld device in the field. I download all data later. It's simple and worth its price and I'm buying a second transmitter tomorrow.

You don't need no more stinking electronics! :p:p:p
 
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