# Long Range Avionics and Electronics

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##### New Member
I'm starting this new thread to get as much information as I can about all of the altimeter, drogue deployments, basic avionics, recovery devices, transmission and receiving video/data, and altitude based deployment devices. I am a partner of JackO. We are both apart of the Chaminade Aerospace Laboratory and I have been tasked with finding sufficient products to make sure we can get video, flight data, and the rocket safely to the ground. For those who have not read up on JackO's rocket, we have just finished our initial tests and are working to create a boosted dart to >150,000 ft.
To start off.
The dart would house all avionics and electronics (and keep them in there safely). Some problems I've been having is finding a purchasable altimeter and deployment system that can function from 150,000-200,000 ft in the air (plus the g force of the dart). There also needs to be a way to successfully transmit HD video from a gopro which is also in the rocket (THIS IS THE MOST IMPORTANT PART THAT MUST BE INCLUDED ABOVE ALL ELSE). We are also trying to attach a streamer system out of the booster and a parachute out of the dart.
For the electronics please also post about the software that would be needed and how to use.
We currently have $500 for all avionics and recovery for everything. I hope it is enough. Please feel free to make a list of parts that will be useful, and send some tips and tricks to JackO and I. Here's the rocket we are currently designing and building: (https://www.rocketryforum.com/showthread.php?138502-Chaminade-Rocket-Club-High-Power-Rocket) (https://www.rocketryforum.com/showt...ltitude-Questions-for-High-School-Rocket-Club) (https://www.dtic.mil/dtic/tr/fulltext/u2/750796.pdf) Thank You, Dongerbreadman #### DongerbreadMan ##### New Member For the live video feed, I have found numerous amounts of drone cameras that would be able to broadcast and is small enough to fit in the payload. I have also found an 18 degree angle downwards to be the best when recording its liftoff. However, the transmission is the biggest problem, while the camera can fit I don't know if the transmitter can fit in a 1.125 inch outer diameter tube. Here is what I was looking at (https://m.aliexpress.com/s/item/325...er-receiver-kit&spm=2114.40010208.4.19.TRO2Ry) I would need to know if that would be sufficient enough to make the trip 30+ miles in the air with live video footage. #### qquake2k ##### Captain Low-N-Slow You certainly have grandiose aspirations. I'll be watching with interest to see if you find any solutions. #### markkoelsch ##### Well-Known Member$500 you say? Do not think that is likely.

There are no altimeters I am aware of that will barometrically work at that altitude. Accelerometers maybe, but again questionable. At that altitude you need to look at sounding rockets- they do a lot with timers.

GPS possible, but again you are talking a fair chunk as just to keep a link you are going to need a sizable transmitter, and possibly an unlocked GPS to get around speed and altitude limits.

I would think, at a minimum, you need to considerably increase that budget. How much I am not sure.

Also, what are you going to use for deployment of chutes at that altitude?

#### ksaves2

I'm not an expert but some of the live video I've seen from amateur rockets has quite a bit of noise and wondered if a circularly polarized or quadrafilar antenna system would be optimal. The antenna system would take more importance if
the power output of the video transmitter were limited due to size and weight constraints. Everything of course can be overcome with brute horsepower (Rf output) but size and weight of batteries becomes critical. You're going to do
a boosted dart to 150k'. I'd say that's pretty optimistic and would venture a guess that the camera is going to reside on the booster and not on the dart. \$500.00 seems lowball for the necessary electronics on a project of this caliber.

I hope you've got access to a rocket mentor who has been close to those altitudes and for the amateur radio TV get an experienced Ham Radio person with a special interest in ATV (Amateur TV). Even then, a Ham person might not
have familiarity of an Rf link from a high G camera venue that might end up spinning at a high rate. Most go with an onboard camera and download the video after recovery. Live feed is only advantageous is you don't
expect to get the rocket back. Plus you'll need to do some test flying on lower impulse motors to see if your setup will hold up. Certainly would be stupid to sling it all together and test fly it the first time with the
high impulse attempt. You do that and I'd say untested your video feed will be crap besides the deal with getting the rocket to affect a recovery. This stuff on satellite repeater stuff may be a valid start: https://www.amsat.org/xtra/Getting Started 3.pdf

The other thing do you have an acceptable venue for the planned flight? I see you're from out West so there are some wide open spaces out there otherwise you'll have some 'splaining to do to the FAA. Kurt

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#### JackO

##### MIT AeroAstro Undergrad -- HSRPL Founder
To provide some details, our mentor was one of the leads on the Reaction Research Society's boosted dart to 50 miles up in 1996. Here is his hilarious and historic article on the event: https://www.rasaero.com/dloads/RRS 50 Statute Mile Boosted Dart.pdf

They were able to transmit video feed back from nearly double our altitude on 90's tech, so I'm confident we can rig up a system for our situation. We have access to many valuable mentors and resources, and as most of you know, I don't shy away from asking for help. Our challenge is going to be getting the transmitter, camera, and gps for altitude recording plus the streamer and timer (timers+streamers are the recovery system of choice for both the booster and the dart as of right now) into as thin a dart as possible.

Weight is not a concern as the dart needs to be as dense and thin as possible for max altitude. The RRS sent a 3.375" dart on an R engine to 270,000', the Super Loki Robin Dart sent a 1.625" dart to 380,000' on an O engine. We can build a P engine, but the altitude is going to be wholly determined by the diameter of the dart which hinges on the size of these avionics.

We plan to launch from Black Rock assuming we can't extend the standing 50k waiver at the Mojave Test Area. We're going2a to test the full avionics system on the RRS' alpha zinc-sulfur rockets before launch in the same way we plan to conduct a full static test of the engine.

-Jack

To provide some details, our mentor was one of the leads on the Reaction Research Society's boosted dart to 50 miles up in 1996. Here is his hilarious and historic article on the event: https://www.rasaero.com/dloads/RRS 50 Statute Mile Boosted Dart.pdf

They were able to transmit video feed back from nearly double our altitude on 90's tech, so I'm confident we can rig up a system for our situation. We have access to many valuable mentors and resources, and as most of you know, I don't shy away from asking for help. Our challenge is going to be getting the transmitter, camera, and gps for altitude recording plus the streamer and timer (timers+streamers are the recovery system of choice for both the booster and the dart as of right now) into as thin a dart as possible.

Weight is not a concern as the dart needs to be as dense and thin as possible for max altitude. The RRS sent a 3.375" dart on an R engine to 270,000', the Super Loki Robin Dart sent a 1.625" dart to 380,000' on an O engine. We can build a P engine, but the altitude is going to be wholly determined by the diameter of the dart which hinges on the size of these avionics.

We plan to launch from Black Rock assuming we can't extend the standing 50k waiver at the Mojave Test Area. We're going2a to test the full avionics system on the RRS' alpha zinc-sulfur rockets before launch in the same way we plan to conduct a full static test of the engine.

-Jack
You have 3 things working against you:
1. High-def live video requires high data rates (>5Mbps) 2.rockets require a low-gain antenna for transmission, and 3. You're looking for range that's longer than what commercial UAVs fly. I think you will have to figure out which 2 out of the 3 objectives are more important to you: Live video, high-def video, high altitude. You may want to shoot for live video with UAV cameras for as high as you can make the link work (use the highest-gain directional antenna on the ground that you can get), and record 4k video on the GoPro.

See the following link for an example of the size and price needed to just transmit standard-def video from that kind of range:

By the way, that article about the boosted dart was a great read.

#### RocketDestroyer

##### Well-Known Member
Do a search on "Amateur fast scan TV". You would need a Technician class license to run FSTV in the 430 MHz band.
https://www.hamuniverse.com/atvfastscantv.html

I know that Kate (https://www.multitronix.com) is way outside of your projected budget but recently Kate was tested to over 318,000 feet and still had a 10dB margin left at that distance. It is an example of what a well engineered system is capable of.

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#### ksaves2

Do a search on "Amateur fast scan TV". You would need a Technician class license to run FSTV in the 430 MHz band.
https://www.hamuniverse.com/atvfastscantv.html

I know that Kate (https://www.multitronix.com) is way outside of your projected budget but recently Kate was tested to over 318,000 feet and still had a 10dB margin left at that distance. It is an example of what a well engineered system is capable of.
They stick a Multitronix setup (Kate) in an Up Aerospace project or what? Kurt

#### JackO

##### MIT AeroAstro Undergrad -- HSRPL Founder
You have 3 things working against you:
1. High-def live video requires high data rates (>5Mbps) 2.rockets require a low-gain antenna for transmission, and 3. You're looking for range that's longer than what commercial UAVs fly. I think you will have to figure out which 2 out of the 3 objectives are more important to you: Live video, high-def video, high altitude. You may want to shoot for live video with UAV cameras for as high as you can make the link work (use the highest-gain directional antenna on the ground that you can get), and record 4k video on the GoPro.

See the following link for an example of the size and price needed to just transmit standard-def video from that kind of range:

By the way, that article about the boosted dart was a great read.

I can safely say that altitude is our top priority. Live video is second and HD video is third. I'm going to get into contact with the RRS member who built the transmitter for their boosted dart, and see what he suggests. But, the plan (read: goal) as of right now is going to be timer+streamer recovery for both the booster and the dart, lower quality video feed and altitude data transmitted live, the smallest HD camera we can possibly find in case we recover the dart intact (standard GoPro is too large), and some sort of GPS or tracking system for altitude measurement and finding the thing. Thanks for your guys' feedback!

-Jack

#### MClark

##### Well-Known Member
When you find a system as discribed in your budget please post, I will be in line for one.

M

##### New Member

I've found two different systems within rf-links.com that can go up to 40 miles and a system from fpvpro.com. I am still researching optimal frequencies and am not yet familiarised with the specifics of this. However within these systems I see that I can shed the case of the device to make room inside the dart. There is also a factor of connection quality, it says that they work with line of sight connection but the antenna inside the payload and I am still working out if the connection will be strong enough for consistent video. I am going ahead to talk to these companies and ask them the same questions. Also, most of these connections take 12V power connections and I am not sure how big of batteries would have to be on board during flight. These batteries would most likely be expensive and heavy so I am also looking into efficient lightweight power cells.

I will be giving an update soon once I get a response from the companies and from a mentor.

#### ksaves2

Technically 1.5Watts on 70cm ham band requires a Ham license to operate and I don't know how one would add a callsign in the transmission. I believe this is one of those gray area
deals. Looks like it has to be used in conjunction with the R/C radio system. Kurt

#### JackO

##### MIT AeroAstro Undergrad -- HSRPL Founder
Right now, we're considering upping our budget and investing in the Kate system. We would have to slim down her bulkheads and maybe rearrange the battery mount etc. to fit inside of our dart. Also, there's the issue of an interior antenna in a steel dart... carbon fiber would melt at Mach3/4. Suggestions?

#### cerving

##### Owner, Eggtimer Rocketry
TRF Supporter
im trying to find a really cheap GPS device. do you think i could convert this into one?
heres the link: View attachment 319103
https://www.aliexpress.com/item/gps...lgo_pvid=ac3ea3d9-993e-45cf-b0a7-3920fba0f0e0
That looks like a automotive version of the cellular "locator" devices that are readily available, and that come with batteries so you don't need to adapt them. The problem is that you need cellular data at the location order for them to work, and (the deal breaker...) these are GSM 2G devices. AT&T shut down their GSM 2G network at the end of last year, so you'll have to go with T-Mobile... their service is unlikely to work at most remote locations.

#### NateLowrie

##### Well-Known Member
Right now, we're considering upping our budget and investing in the Kate system. We would have to slim down her bulkheads and maybe rearrange the battery mount etc. to fit inside of our dart. Also, there's the issue of an interior antenna in a steel dart... carbon fiber would melt at Mach3/4. Suggestions?
I think this is a VERY good idea. If you invest in the system then Vern from Multitronix should be able to help you with the antenna configuration on the dart.

#### JackO

##### MIT AeroAstro Undergrad -- HSRPL Founder
I think this is a VERY good idea. If you invest in the system then Vern from Multitronix should be able to help you with the antenna configuration on the dart.
Nate,

That sounds great, I figured with such a price tag there would be some strong technical support. We may have the time and funds to design and test a rocket engine, but not a high altitude flight computer. We'll contact Vern immediately.

#### BDB

##### Absent Minded Professor
Did I read this correctly? You want to recover your huge booster from a ridiculous altitude via streamer? You're going to need a really large parachute and probably a dual deploy setup. This isn't an Estes Yankee.

#### JackO

##### MIT AeroAstro Undergrad -- HSRPL Founder
Did I read this correctly? You want to recover your huge booster from a ridiculous altitude via streamer? You're going to need a really large parachute and probably a dual deploy setup. This isn't an Estes Yankee.
If we go with Kate, we can think about dual deployment, the reason we plan for streamers right now is because we don't want the dart to drift many miles down range. A large streamer would slow it down enough to save the camera, but prevent it from drifting too far, a compromise between the two of course but much simpler than dual-deployment.

#### BDB

##### Absent Minded Professor
If we go with Kate, we can think about dual deployment, the reason we plan for streamers right now is because we don't want the dart to drift many miles down range. A large streamer would slow it down enough to save the camera, but prevent it from drifting too far, a compromise between the two of course but much simpler than dual-deployment.
Have you calculated the size of your steamer yet? If it's possible, It's going to have to be huge!

Edit: In the initial post you said parachute for the dart and streamer for the booster. In this post, it sounds like you mean a streamer for the dart. That may be possible, but do the math. No one wants your dart carrying thousands of dollars of electronics to come in hot.

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#### JackO

##### MIT AeroAstro Undergrad -- HSRPL Founder
Have you calculated the size of your steamer yet? If it's possible, It's going to have to be huge!

Edit: In the initial post you said parachute for the dart and streamer for the booster. In this post, it sounds like you mean a streamer for the dart. That may be possible, but do the math. No one wants your dart carrying thousands of dollars of electronics to come in hot.
BDB,

You're right, there may not be room, and then we'll go dual deployment. It looks like it will be impossible to slim Kate down enough for the target dart diameter, and if we use Telemetry Pro we'd have to have a 2.5" OD dart. In that case, the altitude will not be nearly as high as was possible before, but this is all planning for something still several months away considering it looks like we're going to do another run of static tests before scaling up.

-Jack