P2V Flytrex Mod, Inside Install..

footsoldier · Mar 1, 2014

Just finished installing and testing my Flytrex, which I installed INSIDE my P2V. I snaked a 18" micro-SD extension cable from the Flytrex board, which I mounted inside w/double-sided 3M, right in front of the battery. Ran the cable through the chassis to the back/outside, Velcro-mounting the micro-SD slot reader just above the battery. Had to remove very little of the case plastic to allow for the ribbon cable. Very small footprint on the outside of the airframe, no hanging wires. Tested it and it appears to be working normally; all good data! I was worried the 18" extension cable might cause a problem, but the flight data is all good.

Here's a couple of photos. I took some pics throughout the install, so if anyone wants more or links to the cable source, lemme know...

kevin_edw2002 · Mar 1, 2014

Great mod!
Could you please send me the link for the cable?

footsoldier · Mar 1, 2014

Here is where I got the cable -- I couldn't find any shorter than 18". Its the best price I could find, but you may be able to find cheaper. It was supposed to ship from Hong Kong, but I got it in seven days from Amazon in KY:

http://www.amazon.com/gp/product/B00DG1DBZ6/ref=oh_details_o04_s00_i00?ie=UTF8&psc=1

Other than attaching the cable, I reinforced the micro-SD card end w/some electrical tape where it would be sandwiched between the two case halves, and velcroed the end against the case upright.

Here are a few more photos...

Pull_Up · Mar 2, 2014

That's a very neat solution indeed. You should post that on Flytrex Facebook or send to Amit if you haven't already as it's a great idea. For a completely invisible fit you could probably mount the actual card reader part inside, to the right of the battery but in easy reach of fingers? Stealth mod!

2trickpony · Mar 2, 2014

Nice mod!

I like it.

bogdanditu · Mar 2, 2014

But what about the termomether on the flytrex? does it still acuratly read temperature if it's indise? and maybe inside its hotter than out...

PJA · Mar 2, 2014

I found one Micro SD that is cheaper and shorter on eBay... USA Sellers...

http://www.ebay.com/itm/Micro-SD-Fl...660?pt=LH_DefaultDomain_0&hash=item257dfc73c4

footsoldier · Mar 2, 2014

I had to check the fine print on those cables, because most go micro-SD to regular SD reader. The regular SD reader means more weight and bigger footprint outside the case. It would probably work, though. I used micro-SD to micro-SD to keep it small and light.

Temp: I suspect that the temperature data would be off, artificially high due to the Flytrex's temp sensor proximity to the P2V battery. I have to admit I forgot about the temp sensor on the board (despite having watched Pull-up's Flytrex video 20 times!), and frankly was more hyper-focused on shooting for a clean, no-wires looking install. I assumed the GPS pass-through and baro sensor would work, and they do. How much the temperature could be off, not entirely sure, but I'll compare some Flytrex temp data against the actual outside temp the next few flights, once it stops raining here. FYI the recorded temp for my 3 min test flight was around 70 F, and the outside temp was supposed to be 67 F.

What is kinda weird is the flight data actually showed a decrease in a couple of F degrees temp over the course of the flight - but that may have been due to increased air circulation inside the P2V case during flight, moving moving more air over the temp sensor and cooling the air around it?

Pull-up, I considered the battery bay access option, and mucked around with installing the card-reader end in the left side of the bay, but in the end it came down to a combination of fat fingers and not finding (read: impatient) a reliable mounting/storage spot for the cable end (getting it out of the way of the battery). It's also not really a standard ribbon cable; it's a very weird flat extension cable with a consistency not far off aluminum foil. I think it is designed to live inside a computer case, and I didn't want to have to manipulate it constantly and risk it breaking.

If the rain holds off today, I'll go flying!

Pull_Up · Mar 2, 2014

The temp sensor in the Flytrex is quite slow to respond to changes. There's normally a lag in my Flytrex data with the thermometer obviously still being a bit warmer from being in the flight case and car showing higher readings than ambient for a while into the flight.

footsoldier · Mar 2, 2014

PJA said:
I found one Micro SD that is cheaper and shorter on eBay... USA Sellers...

http://www.ebay.com/itm/Micro-SD-Fl...660?pt=LH_DefaultDomain_0&hash=item257dfc73c4

Nice find, that cable looks better! The reader housing looks more hardy, and just plain cooler. Dang, I'm gonna hafta get it and crack my P2V back open...

footsoldier · Mar 2, 2014

Pull_Up said:
The temp sensor in the Flytrex is quite slow to respond to changes. There's normally a lag in my Flytrex data with the thermometer obviously still being a bit warmer from being in the flight case and car showing higher readings than ambient for a while into the flight.

Good to know. On a longer flight, w/Flytrex mounted inside, I therefore predict (with zero confidence) an inverted bell shape plotted on the temperature chart: warm car...colder flight environment..increase in internal case ambient temperature (from battery) during flight. All theoretical BS, of course, and the temp data really doesn't make my socks go up and down...the airspeed, altitude, and geo-mapping does...

Pull_Up · Mar 2, 2014

No I agree, I prefer to gauge outside air temperature by how long it takes my hands to go numb - I hate flying with gloves on. The most I'll use is a pair of thin ones with those capacitive fingers so I can control the app.