lipos and altimeters

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ColumbiaNX01

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Let hear what you guys use. Please links to where you got them from. The altimeters that i have and have questions with lipos are as followed. They are installed in a tight spot. Smaller the better. If i had room I would just use 9 volts but don't have that luxury.

Perfect Flight Stratalogger
Perfect Flight Stratalogger CF
Missile Works RRC3
Missile Works RRC2+
Missile Works RTX Transmitter and Receiver


Thanks
 

rharshberger

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Go to HobbyKing and pick the best LiPo for the job and size, HK lists the dimensions (metric HxWxL), weights and C-ratings of all their batteries. Make sure that the max discharge doesn't max the amperage handling capabilities posted by the manufacturers of your altimeters. For transmitter like the RTX the larger the capacity in Mah (generally 2S LiPo's over 950mah are good choices, at least for my Eggfinder TRS) the longer the transmitter will operate. Don't use 1s LiPo's on anything deployment and test the altimeters abitlity to fire the ematch with your lipo. Some batteries HK will also offer with different connectors that may suit your needs, I use mostly JST discharge connectors (balance connectors for charge balancing are JST-XH aka Molex iirc).
 

timbucktoo

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Like Rich says, Hobbyking for Lipos, all 2S.
RTx transmitter, I use the biggest I can fit. Wouldn't use anything less than 500mAh.
For RTx receiver, a 300 mAh will last all day & fits perfectly in case.
Stratologger, 180 mAh.
Missile Works RRC3/RRC2, 9 volt.
 

Ravenex

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I use hobbyking turnigy 2S lipos, 180mah - 300mah for my just altimeters, I use 2s lipo 1000mah or 1500mah for my GPS, and a few different 2S sizes when I'm also power cameras or servos. The trick is to figure out how long they need to run for and what your draw is. For a GPS I want it to run a long time in case I'm out trying to pick up a signal on a lost rocket.
 

OverTheTop

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I use Hobby King LiPos. 120mAh and 180mAh for the pyro channels, 180mAh for powering the Ravens (electronics only, not pyro), and a 1S round 1200mAh for running the TeleMegas.
 

ColumbiaNX01

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I looked on the Perfect flight documents for the Stratalogger CF and it said not to exceed 5 amperers. I was looking at turnigy nano-tech 180mAh 2S 25C. I figured the formula. 180mAh coverted to .180 x 25C = 4.5 amp I am reading that right? That is safe to use?
 

Nytrunner

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If you do use a more powerful battery on the stratologger, you can use two matches in series to help prevent a short.

Worked for me a couple weekends ago when I put a 30C 800 mAh 2s battery on my stratologger.
 

Ravenex

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I looked on the Perfect flight documents for the Stratalogger CF and it said not to exceed 5 amperers. I was looking at turnigy nano-tech 180mAh 2S 25C. I figured the formula. 180mAh coverted to .180 x 25C = 4.5 amp I am reading that right? That is safe to use?
To be honest that doesn't really work, a lipo is capable of putting out much more current than the c rating. The c rating is only the amount they can put out continuously without damage and without a reduction in effective capacity. For example I have 2100 mah 25c 3S lipos, which by your math would be 52.5A max , that I have drawn over well 100A from in bursts.

Putting a properly sized power resistor in series would be an option. My dad does this on all his rockets.
 

OverTheTop

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The c rating is only the amount they can put out continuously without damage and without a reduction in effective capacity.
... and sometimes a certain specified sag in output voltage. Specs can vary wildly but sometimes are indicative of what we need as far as internal resistance in the batteries. A 20C battery of the same size will have a higher internal resistance than a 25C version, if we consider the same manufacturer and model. Batteries with smaller capacity (mAh rating) will have higher internal resistance compared to larger capacity batteries, considering the same manufacturer and model series. That's about all we can say with any certainty.
 

blackjack2564

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Perfect Flight Stratalogger CF
Missile Works RRC3
Missile Works RRC2+
Missile Works RTX Transmitter

3.7v 1cell 750 Mah Turnigy Nano
I have been using this on above units for 2-3 yrs now with perfect functionality. 2 stacked will fit a 9v battery box.
For Gps it will power continuous for 10.5 hrs, one we tested & use . Gps is power hog. [9v will only go 1hr 15minutes]

https://hobbyking.com/en_us/turnigy...ack-walkera-v120d02s-qr-infra-x-qr-w100s.html

Missile Works RTX Receiver. You better use something big...another power hog. I use this. Turnigy Nano 7.4v 2 cell 1500Mah
https://hobbyking.com/en_us/turnigy-nano-tech-1500mah-2s1p-20-40c-lipo-receiver-pack.html

just tape to receiver handle exterior
 

ColumbiaNX01

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Perfect Flight Stratalogger CF
Missile Works RRC3
Missile Works RRC2+
Missile Works RTX Transmitter

3.7v 1cell 750 Mah Turnigy Nano
I have been using this on above units for 2-3 yrs now with perfect functionality. 2 stacked will fit a 9v battery box.
For Gps it will power continuous for 10.5 hrs, one we tested & use . Gps is power hog. [9v will only go 1hr 15minutes]

https://hobbyking.com/en_us/turnigy...ack-walkera-v120d02s-qr-infra-x-qr-w100s.html

Missile Works RTX Receiver. You better use something big...another power hog. I use this. Turnigy Nano 7.4v 2 cell 1500Mah
https://hobbyking.com/en_us/turnigy-nano-tech-1500mah-2s1p-20-40c-lipo-receiver-pack.html

just tape to receiver handle exterior

Thanks jim. What charger do u recommend for these lipos? Do u use just a jst connector?
 

blackjack2564

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Thanks jim. What charger do u recommend for these lipos? Do u use just a jst connector?
I use this one.... it can use 110 wall & comes with 12v clips for charging off car battery at launch site! JST connector for altimeter...batteries have them. Some batteries also have plugs for various planes/cars/drones....you will charge and hook up with JST. This charger comes with balance board for charging more than one cell batteries. In fact if you have room, you can go with 2cell 7.4 volt on altimeters...THAT is a waste on GPS due to it runs on 3 volt clock [transmitter] you just have heat loss going from 7.4 down to 3. So use 3.7 volt on GPS Missleworks if you have one.
https://hobbyking.com/en_us/turnigy...digital-balancing-charger.html?___store=en_us
 
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