GPS nosecone mounting

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Locksmith

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I was looking to get some advice on GPS mounting in my nosecone.
Building my first DD and Tracking rocket for L2 not sure how to mount it.
What do you use?
I have a Missleworks GPS with there whip antenna.
Do you mount antenna up? Down? Other side of board? Out the bottom of the nosecone? Should I replace it with normal antenna?
Any help would be appreciated.

IMG_0759.jpgIMG_0766.jpg
 

rc dude

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I would take out the extension between the GPS and antenna, and then mount it with the antenna pointing towards the nose cone tip. I don't believe it matters if the antenna is pointing up or down, since it should be fairly omnidirectional. Here is how I mounted my TeleGPS in a 54mm nosecone.
20160616_163119.jpg
 

ksaves2

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What kind of rocket is this? Plain fiberglass? Carbon Fiber. If it's plain fiberglass, get a plain bulkhead mount for the antenna and have it facing aft into the main chute bay. You can get bulkhead interconnect cables on ebay:
https://www.ebay.com/itm/SMA-Male-t...029738?hash=item1c6b76c3aa:g:nH0AAOSwA3dYTNZc
just fish around for the connectors you need.
Make sure you don't use metallic paint on this rocket as it can attenuate the signal. Now the paint might not attenuate the 900Mhz band but I know darned well it will for the 70cm band. Use plain, non-metallic paints.

If you have the antenna parallel the tracker that is going to cut down on your range. The MW tracker does 250Mw so it might have some reserve to overcome a sub-optimal antenna installation but you might want to take care to
get all the power out that you paid for. Also try to get an antenna that matches close to your transmission frequency. I use this page for referral for antennas: https://linxtechnologies.com/wp/p/antennas/small-external-antennas/ You can compare the frequency to SWR curves for a given antenna. The closer to 1:1 the more efficient the transmission to free air. Ebay sometimes has Linx antennas up for sale.

You could try a forward facing antenna but a shorter antenna tuned for 900Mhz is less efficient. If MW supplied that antenna for you, knowing Mr. Amos, it's probably optimized for your Rf module so I'd have it face aft and be sure the upper bay tube is radiolucent.

Be aware that black colored fiberglass, though it may not contain carbon fiber thread, does contain carbon black and it can modestly attenuate the Rf signal. One fellow used sensitive testing equipment here and found a 1db loss. Not too bad but I've decided to run a 100Mw Beeline GPS tracker on the 70cm band (425Mhz) in a carbon black nosecone instead of a 16mW one. Again your MW tracker goes at 250Mw so if your nosecone shroud is black colored fiberglass, you should be in good shape. Of course, if you use that aft bulkhead facing antenna wouldn't be an issue.

Lastly, no matter what you do, do a range check out in the open if you can. If you have the aft facing antenna, do something like I and do put the NC in a box and set it on top of my tabletop chimney of a single story house and do a down and dirty range test. You could hoist the nosecone up 10 feet into a tree or put it on top of a 7 foot step ladder and walk away with your receiver and see how far you can go. Whatever you do, do not omit a range test.

If you've never GPS tracked before, consider using a lower impulse motor to keep the rocket pretty much in sight or minimize the out of sight time so you stand a very good chance of getting the rocket back if there is something
lacking with your installation. It that goes O.K then if you must, punch it for the certification. Oh, I've heard recommended if there is tall grass or thick foliage, put a beeper on your harness somewhere. I had
an experience in a no-till corn field I thought I was right on top of an EggFinder GPS with the receiver beeping away and I couldn't see it. Boy did I feel stupid with no beeper on board the rocket. Stupidhead realized
I needed to zoom in the map on my tablet and I went right to it. GPS will get you pretty close but not always right on top of it though.

If you are going to manually input lat/long into a handheld mapping GPS, make darned sure you are well practiced using the right units and convention from your receiver to your handheld mapping
GPS. Using degrees decimal degrees? Degrees, minutes, decimal minutes? Degrees, minutes, seconds? If you get the units messed up and don't have backup, you could be SOL. Wouldn't matter if the flight was a success, if you can't find it, it's a DNF. Don't laugh, I've seen a fellow do it with APRS tracking! Took him forever to find his rocket. He's been a happy camper since I saw that a simple cable between his APRS radio and Garmin mapping GPS was all he needed to automatically track. Just watch the screen.

Also, consider a higher main deployment altitude if your venue allows 800, 1000 or 1200 feet even. I never go less than 800 feet with flights that are going out of sight for a long time. The reason is once under main, with the slower
descent, GPS tracker position reception (or APRS packets for the ham stuff) settles down and more position/packets can be received to generate a trend line at altitude. This is more helpful with map plotting as opposed for
one who simply gets the last received position and then "goes there" to either find the rocket or get within the ground footprint of the tracker to get that final position if it isn't already seen.

As I understand it, the Missileworks receiver can be interfaced with Bluetooth if it has a module and tracking similar to this can be had: https://www.rocketryforum.com/showthread.php?137555-Eggfinder-Map-tracks

I also suspect "GPS Rocket Locator": https://play.google.com/store/apps/details?id=com.frankdev.rocketlocator will work too but Google maps do not work anymore. The open source OSM still works and is cacheable for
offline use. Me suspects Google is getting squirrelly with people using their "stuff". Best of luck. With a little practice you'll bulletproof your L2 attempt. If push comes to shove, at least you'll know which tree its in!! :surprised::wink: Kurt
 
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Locksmith

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Ty for ty info, rocket is mac performance fire stick with wildman black nosecone.
for receiver I have both the Bluetooth and navigator version already assembled in their 3D case as well as an upgraded antenna. My plan is to either use my iPad if I can find software or a laptop to receive and plot live through Bluetooth as backup but use the MW navigation to find rocket.
My only worry is if I send the antenna through the bulkhead won't the harness just beat it to pulp while on parachute? The cable it came with is through hole so I have everything for it just wasn't sure how safe it would be with harness attachment being an inch away. As well antenna being that far In payload bay, couldn't the parachute pushing its way out on deploy bend or break it?
What about only sending say a inch or 2 out the aft bulkhead?

i like your idea about putting nosecone in tree I live in country so their is miles of open area but there is a lot of hills time to find a tree on a hill and see what kind of range I get.
thanks again for info
 

ksaves2

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Ty for ty info, rocket is mac performance fire stick with wildman black nosecone.
for receiver I have both the Bluetooth and navigator version already assembled in their 3D case as well as an upgraded antenna. My plan is to either use my iPad if I can find software or a laptop to receive and plot live through Bluetooth as backup but use the MW navigation to find rocket.
My only worry is if I send the antenna through the bulkhead won't the harness just beat it to pulp while on parachute? The cable it came with is through hole so I have everything for it just wasn't sure how safe it would be with harness attachment being an inch away. As well antenna being that far In payload bay, couldn't the parachute pushing its way out on deploy bend or break it?
What about only sending say a inch or 2 out the aft bulkhead?

i like your idea about putting nosecone in tree I live in country so their is miles of open area but there is a lot of hills time to find a tree on a hill and see what kind of range I get.
thanks again for info
With the iPhone you're going to end up having to input the lat/long manually into a program to get a position on the map. I believe people use
Motion-X. I'm not aware of a live tracking app that will work with the iPhone and rocket trackers (I suspect there may be APRS stuff). iPhone users
jump in and correct me as I don't own an Apple device.

Get a cheap, used Nexus tablet with 32 Gb and you'd be in good shape with GPS Rocket Locator. Kurt
 

Bat-mite

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I stick mine in a piece of foam rubber pipe insulation the length of the NC and shove it in. No mounting. If it is a plastic NC, I cut a door in the shoulder and stick a piece of masking tape over it. For a FWFG, you can still do this while the bulkhead is off.
 

ksaves2

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I would take out the extension between the GPS and antenna, and then mount it with the antenna pointing towards the nose cone tip. I don't believe it matters if the antenna is pointing up or down, since it should be fairly omnidirectional. Here is how I mounted my TeleGPS in a 54mm nosecone.
View attachment 315916
The only thing I'd add to this is you might want to restrain that battery in a more sure fashion because if the NC takes a good hit and it breaks forward to hit the Tele-GPS, you might trash it in a hard but not generally fatal landing.
If your flights are always perfect you'll be fine but me I'm not always so lucky. Kurt
 

BDB

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With the iPhone you're going to end up having to input the lat/long manually into a program to get a position on the map. I believe people use
Motion-X. I'm not aware of a live tracking app that will work with the iPhone and rocket trackers (I suspect there may be APRS stuff). iPhone users
jump in and correct me as I don't own an Apple device.

Get a cheap, used Nexus tablet with 32 Gb and you'd be in good shape with GPS Rocket Locator. Kurt
I'm still pretty new to tracking, but I have three flights using an EggFinder and Motion-X on my iPhone. Works fine.
 

Locksmith

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I'm still pretty new to tracking, but I have three flights using an EggFinder and Motion-X on my iPhone. Works fine.
Well I bought Motion-x and then found out that missleworks use a SPP Bluetooth module which apple does not support so it will not connect to it no matter what. Guess Im gonna have to buy a Android tablet :/

Thanks everyone for their advice and input this is what I ended up doing.
Removed the jumper wire, and mounted it so a little over an inch sticks out the bottom.
Used Binder design screw switch on bottom with a 1000mah lipo I figure I shouldnt have to worry about turning it on at pad and can start it during assembly. I may switch to 2c lipo if I notice in increase in distance during tests.
I also left about 4" above the board and below the tip for weight. I plan on using old lead pipe as weight if needed. "think giant thick heavy washers"
Still have to tidy up the wiring and few odds and ends but this will give you the general idea.
IMG_0767.jpgIMG_0768.jpgIMG_0769.jpgIMG_0770.jpgIMG_0771.jpg
 

BDB

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Well I bought Motion-x and then found out that missleworks use a SPP Bluetooth module which apple does not support so it will not connect to it no matter what. Guess Im gonna have to buy a Android tablet :/

Thanks everyone for their advice and input this is what I ended up doing.
Removed the jumper wire, and mounted it so a little over an inch sticks out the bottom.
Used Binder design screw switch on bottom with a 1000mah lipo I figure I shouldnt have to worry about turning it on at pad and can start it during assembly. I may switch to 2c lipo if I notice in increase in distance during tests.
I also left about 4" above the board and below the tip for weight. I plan on using old lead pipe as weight if needed. "think giant thick heavy washers"
Still have to tidy up the wiring and few odds and ends but this will give you the general idea.
View attachment 315958View attachment 315959View attachment 315960View attachment 315961View attachment 315962
Sorry. I should have mentioned that I get the coordinates from the Eggfinder LCD receiver and type them into Motion-X. Your setup looks great!
 

ksaves2

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Well I bought Motion-x and then found out that missleworks use a SPP Bluetooth module which apple does not support so it will not connect to it no matter what. Guess Im gonna have to buy a Android tablet :/

Thanks everyone for their advice and input this is what I ended up doing.
Removed the jumper wire, and mounted it so a little over an inch sticks out the bottom.
Used Binder design screw switch on bottom with a 1000mah lipo I figure I shouldnt have to worry about turning it on at pad and can start it during assembly. I may switch to 2c lipo if I notice in increase in distance during tests.
I also left about 4" above the board and below the tip for weight. I plan on using old lead pipe as weight if needed. "think giant thick heavy washers"
Still have to tidy up the wiring and few odds and ends but this will give you the general idea.
Make sure you do a range check with that paralleling all-thread. It may cut down on your range. Do a range test in the nosecone and one with the MW GPS out in the open. If there is no difference or a decrease you can live with
you're good to go.

You might go to the EggTimer site and look at the tips for flying an EggFinder. They pertain to the frequency range the MW unit uses in the 900Mhz range and are just as applicable: https://www.eggtimerrocketry.com/attachments/File/Eggfinder_Users_Guide_RevB6.pdf Kurt
 

Locksmith

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yea I was a little worried about the threaded rod, just couldn't think of any other way to do it. I might order some nylon threaded rod if I can get some info on its shear strength.
 

ksaves2

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yea I was a little worried about the threaded rod, just couldn't think of any other way to do it. I might order some nylon threaded rod if I can get some info on its shear strength.
I wouldn't trust nylon as you might have to compromise your deployment charge. Rip the bulkhead off and you might get an idea of where the nosecone hits ballistic.

If your range check is zilch, you could still modify it with a bulkhead mount for the antenna so it faces aft in the main chute bay if you have the room. The 250mW output from your tracker might overcome the situation fine for your purposes. When flying the 100Mw EggTimer stuff I try to optimize the install as close to ideal as I can as I've noticed that a fair proportion of the positions are not plotted on the map. That may be due to the hacked software I'm using but there are certainly enough relayed back to recover the rocket.

I haven't lost a single rocket where the tracking system (APRS or NMEA ISM band) was functioning until landing or impact! The ballistic one only had 2 or 3 positions but that's all it took to find the fin can sticking out of the ground.

Again, if you've never tracked in this manner, I recommend a shakedown flight with a lower powered motor to facilitate a visual recovery just in case the tracker doesn't work out. If a lower powered J motor can be used, you can get
your certification done and maybe have the ability to recover visually as a backup. Once you get confident, you can really punch it and prepare to be surprised. Sometimes you presuppose where the rocket is going to go and
your tracker tells you otherwise and it's the difference between losing it and finding it. Kurt
 

soopirV

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With the iPhone you're going to end up having to input the lat/long manually into a program to get a position on the map. I believe people use
Motion-X. I'm not aware of a live tracking app that will work with the iPhone and rocket trackers (I suspect there may be APRS stuff). iPhone users
jump in and correct me as I don't own an Apple device.

Get a cheap, used Nexus tablet with 32 Gb and you'd be in good shape with GPS Rocket Locator. Kurt
I've been using Motion-X on my iPhone and MapSphere on a Windows tablet with good success, but wanted to play with the GPS Rocket Locator- in the Play store, however, it's saying it's not available in my country (US) yet...but maybe that's a weird effect of my firewall at work?
 

Locksmith

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Well I didn't have much time due to crappy weather but I did do I quick test. I set nosecone on a big rock in front of yard and starting driving Lost line of sight due to some trees at around 3808 ft. then drove back different route and it picked it back up at about 1 mile away. That is with it being only a few feet above the ground and me driving around with receiver out the window. Not sure if thats good, bad, average, great?

I also was having trouble with navigation portion of the receiver apparently I must of disabled it in the setting cause it only displayed the rockets gps location and the buttons on receiver did nothing.

Another side note I purchased a "better" antenna for receiver on amazon a Techtoo 5dbi and it lost signal at about 1500 ft away glad I brought original with me since the new one was garbage but I should of know since it is a 700-2600Mhz gonna have to look for a more of a dedicated 900Mhz one.
 

ksaves2

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A mile is pretty good range on the ground but I've only had exposure to 100mW units. You need to also test with the unit out in the open outside of the nosecone to compare the two results. If it dramatically increases outside of the the nosecone, you
might have to consider a change. A patch antenna is what you should consider: https://www.l-com.com/wireless-antenna-900-mhz-8-dbi-flat-patch-antennas

You can shop around for a better bargain and there are some do-it-yourself articles out there. Kurt
 

Locksmith

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A mile is pretty good range on the ground but I've only had exposure to 100mW units. You need to also test with the unit out in the open outside of the nosecone to compare the two results. If it dramatically increases outside of the the nosecone, you
might have to consider a change. A patch antenna is what you should consider: https://www.l-com.com/wireless-antenna-900-mhz-8-dbi-flat-patch-antennas

You can shop around for a better bargain and there are some do-it-yourself articles out there. Kurt
I will try and do a test with gps out of nosecone and see if it makes a difference when I also test 1cell - 2cell - 9v. Not sure if voltage makes a difference but I know it does on the receiver, when I had 1 1c lipo in receiver I could hardly read the lcd screen put 9v in and looks great.

That must be a new offering when I ordered the rocket I purchased the other nosecone electronics kit, but really wanted away to change the nosecone weight anytime thats how I decided on full thread. Again probably not my best idea but im learning.
 

DavidMcCann

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That must be a new offering when I ordered the rocket I purchased the other nosecone electronics kit, but really wanted away to change the nosecone weight anytime thats how I decided on full thread. Again probably not my best idea but im learning.
I'd do a few tests and see if it's really an issue for you. It might not be. As for nose weight, hopefully you won't need any. I've got these nose bays on a couple rockets, mostly because its easy to pop them open, toss in some foam and my loose tracker, more foam and close it up and fly.
 

soopirV

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I tested my Eggfinder a few years ago, when I first got it, and got 1.25 miles out of it. This was with the Tx sitting at home on my back patio, and the Rx with me at work- I was able to pick up the signal by walking out to the parking lot. Capture2.PNG
 

Oberon

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I would take out the extension between the GPS and antenna, and then mount it with the antenna pointing towards the nose cone tip. I don't believe it matters if the antenna is pointing up or down, since it should be fairly omnidirectional. Here is how I mounted my TeleGPS in a 54mm nosecone.
View attachment 315916
This is a nice looking GPS bay, but I'm at a loss for how you actually install this - how is the bulkhead secured to the nosecone when you're ready to button up and fly?
 

dhbarr

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This is a nice looking GPS bay, but I'm at a loss for how you actually install this - how is the bulkhead secured to the nosecone when you're ready to button up and fly?
My money's on a ring mounted in the NC. I see some screwholes in the ringplate.
 

rc dude

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This is a nice looking GPS bay, but I'm at a loss for how you actually install this - how is the bulkhead secured to the nosecone when you're ready to button up and fly?
There are four all-thread couplers with short sections of all-thread epoxied inside the nosecone. I added the short section of all-thread to give the epoxy more to grab onto.

This is looking from the front before I epoxied the coupler into the nosecone. (the bits of wire were just spacers while the epoxy cured)
20150313_173840.jpg

And the four screws that hold it on.
20150313_173845.jpg
 

OverTheTop

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Here is what I have done on a sled that fits 54mm with a TeleMega:
sledbottom.JPGsledtop.JPG

What is not obvious is that the antenna wire is actually spaced above the G10 by feeding through holes in the M5 nylon screws I am using for spacers. It makes a slight difference to the antenna tuning (a bit closer to air than the G10 dielectric). Probably does not matter much.

It mounts in a 4" 3D printed NC, but I can print an adaptor for 54mm (or whatever). Thread is here:
https://forum.ausrocketry.com/viewtopic.php?f=6&t=5019&start=16

Antenna up or down for you probably doesn't matter much. Try to keep it away from the GPS as it may overload the front end on the GPS reducing sensitivity somewhat. Make sure you test it well.
 
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jeff2space

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This is the setup I'm using for a Missile Works RTx/GPS unit in the ImageUploadedByRocketry Forum1491354269.236264.jpgnose of a Wildman Drago 4XL. It has not flown yet.
 

BDB

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Has anyone mounted a deployment altimeter or an altimeter/gps system in the NC? I'm currently building a 3" rocket and I want to mount an Eggtimer Quantum in the NC so I can fly research motors without deployment charges. I'm particularly interested to see how people position the charge well on bulk plate and vent hole placement.
 
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OverTheTop

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Holy crap! That was an amazing thread. Thanks.
No worries. Thanks. I use that NC on my Velociraptor as a regular flier as well. I usually run drogueless dual deploy, just blowing the NC off at apogee, with altimeters (twin Ravens) in the main airframe blowing the chute out for landing.
 
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