What Battery???

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bill2654

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Im installing a Eggfinder in a 29mm nosecone. This is a the type of NC that the shoulder is glued in separately. So essentially everything has to fit in a 29mm coupler. Which 3.7v Lipo battery fits in a 29mm coupler? Im assuming it has to be a 1S cause my 2S aren't going in. Can somebody post a link?
 
I don't think an eggfinder will run off a 1s LiPo 3.7v. Or it won't run for any length of time. I ve set mine up with a 2s and attached it with heatshrink tubing. (See Picture)

Tracker1.jpg


Tracker2.jpg
 
Hi Bill, hoping you have a great new year!

This is the largest I could find that will fit. Runs my MissleWorks Gps for 10 hrs continuous. [did the testing]
It will just fit & slide in easily, no need to force. 750 ma
White connector not needed. [in my application ]

DSCN5538.jpg DSCN5541.jpg

https://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=59368

Coupler from 29mm BlackHawk.

Edit: don't know anything about Eggfinders or if 3.7 will run them.
 
Last edited:
from eggfinders web page...
What kind of battery does the transmitter require?

We recommend using a 7.4V ("2S") LiPo battery, at least 300 mAH. You CAN use a smaller one, the Eggfinder TX draws about 70-100 mA when it's running, but that will reduce your operational time, of course. If you want to use a smaller battery we recommend that you power it up shortly before launch... mounting it in the nose cone usually makes that pretty easy to do.
____________________________________________________________________________________________

This one looks like it should work. https://www.hobbyking.com/hobbyking/store/__26739__Turnigy_nano_tech_300mah_2S_45_90C_Lipo_Pack.html
It as smaller diameters then the battery Jim listed.

Tony
 
I've found when letting the EggFinder run for 10hrs (off a 1500mah pack for testing) takes about 600 to 700mah to charge the pack back up. Gotta love these Eggfinders. Figured out how to configure a tracking program that plots it in real time on an
8" Windows tablet. It's not the Android app GPS Rocket Locator but APRSIS32 that will allow one to download zoomable maps for storage on the device for portable off grid/internet use. Can't wait to fly it in the spring.
An even easier program to setup, YAAC, is waiting in the wings once Windows Bluetooth pairing can be remedied. YAAC is the one I'll be able to get a one page instruction sheet off so anyone could slap it on a 7 or 8" tablet for a portable
mapping solution.

The thing about real time tracking is one can monitor and be looking in the right direction for the expected main chute deployment to get a possible visual fix. I've tracked a lot of APRS rocket trackers where the rocket takes a change in
direction with the winds aloft and everyone is looking the wrong way for the expected deployment. Kinda hard to get an idea by monitoring numbers off an LCD and getting the positions seamlessly and automatically into a mapping application
is a big advantage for in flight monitoring.

Kurt Savegnago
 
I've found when letting the EggFinder run for 10hrs (off a 1500mah pack for testing) takes about 600 to 700mah to charge the pack back up. Gotta love these Eggfinders. Figured out how to configure a tracking program that plots it in real time on an
8" Windows tablet. It's not the Android app GPS Rocket Locator but APRSIS32 that will allow one to download zoomable maps for storage on the device for portable off grid/internet use. Can't wait to fly it in the spring.
An even easier program to setup, YAAC, is waiting in the wings once Windows Bluetooth pairing can be remedied. YAAC is the one I'll be able to get a one page instruction sheet off so anyone could slap it on a 7 or 8" tablet for a portable
mapping solution.


The thing about real time tracking is one can monitor and be looking in the right direction for the expected main chute deployment to get a possible visual fix. I've tracked a lot of APRS rocket trackers where the rocket takes a change in
direction with the winds aloft and everyone is looking the wrong way for the expected deployment. Kinda hard to get an idea by monitoring numbers off an LCD and getting the positions seamlessly and automatically into a mapping application
is a big advantage for in flight monitoring.

Kurt Savegnago

I have been reading your other threads on your progress with this tracking program. Great work! I see a "Sticky" at some point in time when everything is up & running to your satisfaction.
I have one of those MW RTx units on pre order, and would someday be interested in something more than arrows on a LCD display. An expensive rocket that launches straight up and vanishes for what seems an eternity......."Dude, where's your rocket?"
Anyhow, I have a feeling YOU & Jim(blackjack2564) will be answering a lot of Q's in the near future about how to set up these trackers - so we get high flying rockets back. Many Q's have already been answered in other older threads.

I, like Jim, am still on flip phones, but I always wanted a Win Tablet. Hmmm. Will all this work with the MW RTx?
Thanks Kurt & CJ!

Now back to "What Battery???"
 
I like that 300mah 2s cell shown. I best get me a couple for smaller rockets. Query Jim about the MW, It depends on the encoding that's used whether or not it can be directly plotted on a map. Same with the AIM unit. I don't know what the protocol is with the MARSA54L system soon to be available. Direct "no touch" data transfer is helpful to
prevent wild goose chases from "imperfect" data keying.

Jim has much, much, much more experience than I but I bet he likes going directly after the rocket and not messing
with waving the Yagi. I bet he's great at it but it' so much easier to walk (or ride) to a point on a map, get back
and fly the next project instead of wasting time trying to find the last one.

The issue with the 1S cells is they start out at 4.2V and I believe it drops pretty quickly if used with the EF. Power output on the transmitter also could drop in a quicker fashion. If the rocket sits on the pad for a time or it's cold out, might have "some tracking issues".

I bet the 2S 300mah batt would give at least 2 solid hours and leave enough so one can safely recharge the battery.
One doesn't want to drain these things to "zero" as you can send it to the recyclers then. Can't to anything to save the pack. They don't have a discharge limiter.

Believe me, I've done it while software testing, went to bed and forgot for a day. Lost two 1200mah packs that way.

Kurt Savegnago
https://aprs.fi/#!mt=roadmap&z=11&call=a/QCRS&timerange=3600&tail=3600

https://aprs.fi/#!mt=roadmap&z=11&call=a/PARS&timerange=3600&tail=3600
 
I've used 2S batteries as small as 180 mAH in small rockets (like an Estes Mongoose, for example...). They'll easily fit in a 24mm tube, but if you have 29mm and a little room it never hurts to go big, unless you're REALLY counting grams.
 
Hi Bill, hoping you have a great new year!

This is the largest I could find that will fit. Runs my MissleWorks Gps for 10 hrs continuous. [did the testing]
It will just fit & slide in easily, no need to force. 750 ma
White connector not needed. [in my application ]

...............

White connector not needed for your application, but needed for balance charging and individual cell voltage checks.
 
Thanks everyone! I see some of the batteries only have the white charging connectors and no JST connector. All of my batterys have JST connectors AND the white charging connector. How can I make these others work without the JST connection?
 
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