Mounting Eggfinder in Rocket

I was curious for people to share their mounting techniques for the Eggfinder, or any other GPS telemetry units that must be mounted away from metal that may interfere with the broadcast signal. I was originally planning on mounting the Eggfinder somehow in the nose, but now I'm just thinking about 3D printing an enclosure for it and attaching that to the shock cord.

Concerns with that method are a large jolt to the electronics board, but I think as long as it's well soldered and the batter leads well connected that shouldn't be an issue.

Inputs? Ideas? I'd like to shoot any and all holes in this plan now before I attempt to fly it.

Jacob, see if you can do a search in the electronics thread. Some folks posted ebays for the E.F., specifically nosecone bays. The key is not to have all-thread parallel the antenna. If you do a closure, get a bulkhead mount like this: https://www.ebay.com/itm/4in-4-SMA-...xtender-Jumper-Cable-RG316-10cm-/161046398475. Especially if you use the RP-SMA connector on the EF board that Cris can provide. You put the bulkhead mount on the "containment box" and attach to the EF that's securely mounted inside the box.

Also, it depends upon the diameter of the nosecone one is going to use. Four inch or greater diameter nosecone is easier than a smaller one to do an internal mount. Kurt

Thanks for the link Titan II, looks like a pretty simple method. I'm still curious if I can just mount directly to the shock cord. Would make it incredibly simple to move from rocket to rocket, and obviously wouldn't require any extra work on the nose cone.

Titan II said:

https://www.rocketryforum.com/showthread.php?64489-Tracker-Nosecone-Mounting

Click to expand...

https://www.rocketryforum.com/showthread.php?67581-Eggfinder-Bay-Examples&p=731953#post731953

Found another one. Kurt

Awesome, thanks! Turns out I misspelled when I initially searched the forum... didn't mean to post something that's already been talked about quite a bit.

jmight said:

Awesome, thanks! Turns out I misspelled when I initially searched the forum... didn't mean to post something that's already been talked about quite a bit.

Click to expand...

Use a bulkhead antenna mount so the connector on the EggFinder board doesn't get stressed. There are a lot of antennas on ebay to peruse. Make sure the EF is mounted securely internally and that the connection to the shockcord is bulletproof. Kurt

I also have a version for smaller rockets and it is like what you are talking about. It is a 1.2 x 8 inch tube with one fixed and one removable cap on the ends. I tape the eggfinder and a 120 mAh 2S battery to a strip of balsa the length of the tube inside. Tape the whole thing to your drogue shockcord.

ksaves2 said:

Use a bulkhead antenna mount so the connector on the EggFinder board doesn't get stressed. There are a lot of antennas on ebay to peruse. Make sure the EF is mounted securely internally and that the connection to the shockcord is bulletproof. Kurt

Click to expand...

What do you mean by bulkhead antenna mount?

I shape a piece of thin(ish) ply such that it fits exactly in the nose cone as a sled and then masking tape the electronics to the ply and add some foam in the directions it's likely to see shock from. When the NC bulk plate is installed it fits right against the sled and holds it securely. The advantage here is no metal required.

This configuration survived a cato at Mach 0.5 which deployed the main chute sufficiently violently to rip it apart and the rocket then fell 1000 feet to the playa with no chute. The av-bay and contents in the nose cone were completely undamaged.

I think some of the AV bays folk build are awesome, but you can also do something really simple if you think about the requirements you have to protect the electronics.

jmight said:

What do you mean by bulkhead antenna mount?

Click to expand...

https://www.ebay.com/itm/4in-4-SMA-...Jumper-Cable-RG316-10cm-/161046398475?afsrc=1

If you mount the EF in a box, use the bulkhead mount to take the load so if the antenna breaks, you don't snap off the connector on the board. Kurt