Click Images to Enlarge
 

 

 ---   DJI Phantom 4
 
Mfg:   DJI
Model:   Phantom 4 (USA) (sn 07DDD5D0A11035)
Specs:   http://www.dji.com/product/phantom-4/info#specs
 
  Quad-X Type

 

 
<---<  ..Click & Drag Image Above  or  Hover & Rapid Fire Left Mouse Button..  >--->
   
  ..by request, I will start uploading some of my local scenery taken with the Phantom4.. see btm of page..  
 

..29Jun2016, just received this P4 and so far have only ran 3 batteries, approx 53min of very cautious flights, have not tested any of the 'extended features', yet, but so far there's no doubt in comparison to the Inspire1 (which is Good) the stability is Rock-Solid.. the Obstacle Avoidance Sys coupled with the Vision Positioning Sys takes a lil getting used to.. for instance, flying over a pitched roof it tends to actually fly or drift backwards several feet rather than hover in place.. also there seems to be an intermittent loss of altitude i.e. dropping several feet, its not a drastic drop.. but its there and must be monitored.. the diff in pwr btwn the Inspire1 and the P4 was to be expected, however, it is a Big Diff.. and unless I have another issue the Ctrl's (Rudder Response) seem Mushy, this is confirmed by the data extracted from the flight-log thanks to Healthy-Drones (delay's from 0.5sec up to 1.0sec).. also Battery Temp, the Inspire1's battery bay is basically open, lots of surface area to dump heat, whereas the Phantoms battery is buried inside the fuselage.. the battery itself is vented, but I think the drone or the arms should somehow be ducted to help with the cooling.. then again maybe I'm just not used to see'ing Batt Temps >140F.. obviously I'll keep testing and getting used to the Phantom but these are my first impressions..

..continued testing the Phantom to verify whether I had a lemon or not, at the 5th Battery it flew as if it were a different Phantom, Rudder response is Now NORMAL, Quick, Snappy.. so..? Break-In Period? Too Much Lube on a JoyStick/Encoder..dunno, I was advised by DJI Cust-Srvc or OnLine-Cut 'n Paste Tech(s) to make adjustments to the GAIN & EXPO Tuning and to Rely on the App to Warn me if there were any Temperature Related Issues, for whatever reason they refuse  to give out a 'Normal Operating Temp Range' for the 'Batteries', but did tell  me that if they were to reach a 'Threshold'  >60C /140F that I would be Prompted and that I Should Land, I got No Warning Indication or Prompt.. so anyway, I Made No, None, Zero  Adjustments to GAIN or EXPO, this is a brand new craft, IMO it shouldn't need any adjustments and as far as the battery temp issue, I attribute the excessive temp (143.5F) due to my overly cautious flying the 1st day, And will continue to monitor the Battery Temp(s) with the Hands-On Approach, there is No Such Thing as a Software Magic Carpet, read the NewsGroups, SIG's and Forums, they're loaded with horror stories of people relying solely on the Software.. Software is not a substitute for hands-on experience in this case..

..Do I still have a bad taste in my mouth with DJI in ref to the Inspire1 and the lack of Structural Repair Parts and Post-Sale Cust-Srvc, Absolutely YES, I think its a piss-poor business model (but then again a Casino is profitable, and, the customers keep coming back, pay out just enough warranty claims to keep up the perception, hmmm), but its one that is becoming more and more common with such a Dumbed Down Public unwilling or too lazy to think for themselves.. but this is not a manifesto, this is about the/my  Phantom4, and DJI has got it right with this one.. having only flown it for approx 18hrs (140hrs now) I gotta say 'it Does Exactly What its Advertised to do, Right out of the box'.. will there be defects here and there, of course, its a mass-produced product.. the Problem for DJI is.. all a competitor has to do now is copy the Phantom4, give it a Sexier Fuselage and they'll have a winner.. (hmmm Walkera Scout with Phantom4 Guts............)

..in-Flight UpDate..

..Update: DJI does it again, ..and again.. ..05Jul2016, flying my Phantom during the day, lil more difficult because the tablet screens are hard to see in bright light.. during my flight, Phantom is approx 2200ft dwn range, a window pops up on my screen, is it High Contrast.. phhhftt No, I cant read it, but I still have ctrl and can see enough of the edges of the screen to safely fly it back to Home-Point.. get it into the shade and now I can see the Geo-Fencing Warning incl the Check-Boxes & Confirm Button.. ..and again? ..06Jul2016 while setting up to fly, my tablet is force fed the DJI-Go v282 Update, at the time I didn't notice it, there was No Change in the UI and I don't typically Check Sftwr Versions pre-Flight (well I didn't then..) what I did notice was massive Live-Video Artifacts, Pixilation etc.. bad enough that it would block the screen 90% of the time, so I landed, checked connections ..etc.. attempted 2 more flights.. same thing.. landed again, checked all settings incl sftwr versions and found that I'm now running v282..! so I try to fly again, once motors started, (Audible) '..Home Point has been UpDated, Check it on the Map..' click the map, App Crashes, 6x in a row (btw the app did generate 6ea Crash-Logs & 15ea Flight-Logs! in this process) ..so that pretty much ended my flying for the day.. removed 282, reInstalled 281, immediately Google DwnLd Mgr attempts to reUpDate.. whats particularly galling about all this is DJI apparently does No Testing Prior to Distribution of these Updates not to mention the fact that each of the Updates are like a Blivit (10lbs of sht in a 5lb bag), a One-Size Fits All Piece of Sftwr.. I personally don't think it can be done.. and honestly don't think it should be done with these aircraft.. ..oh and included with the  v282 Update was a multi-page, fine-print type document (EULA or Terms of Use, hmm can't find it anywhere) basically free'ing DJI of any liability.. for Anything,, and by Running the App or Product you assume ALL responsibility and/or liability..  this may have been included with the other updates I don't know.. this is the first (and last) update that I've inadvertently allowed shoved dwn my throat..

DJI - Terms of Use (01Jul2016) - 9 page scrn capped PDF Document approx 11mb

..UpDate: approx 25Jul2016 DJI releases DJI-Go v283 with added support for the Zenmuse Z3 Camera & Bug Fixes (the Z3 features an optical zoom lens, It provides a 3.5 optical zoom and 2x digital zoom), 15Aug2015 figured I'd install v283 to test and make sure there there wasn't real issues or nasty bugs I couldn't live with prior to purchasing the Z3.. Installed v283 and Took-Off, 'IMMEDIATELY'  I noticed a substantial decrease in acceleration (later confirmed by way of FWD Pitch degree's, prior 18-20, post 12-15), I assumed at the time it was an attempt to address the heat issue, so I continued to fly it, approx 6ea batteries (27 Flights Now) and from those few tests it does appear to have addressed the heat or Over-Heat Issue.. also, the Altitude Variance Issue seems to have been addressed at least with my Phantom 4 and I thank DJI for the effort even though regarding the heat this is only a band-aide the P4 or the Next Model Actually needs more ducting to allow it to dissipate the heat generated more efficiently (if I currently had access to a Mill I'd prove it, fill a New P4 Shell with amalgam, mill several strategically placed slots so as not to weaken the air-frame but allow more air flow in and out of the fuselage, Why? because Heat is a Cancer to electronics)., prior to this with ambient temps ≥80F unless you continued to move at speed throughout the entire flight, And, flew it at or near 20min the battery would reach the DJI stated threshold of 60C or 140F.. so just buzzing around the yard was pretty much out of the question unless you flew much less than the full capacity or flight-time of the battery..

..the Altitude Variance Issue has been reported by many in the forums, the Heat on the other hand, I haven't found or read Any., simmering their props @140F to Die them some butt-ugly color or Putting the Entire Craft Inside the Refrigerator to Calibrate it, dozens, it's about as ridiculous as smoking banana peels.. my guess is that the majority rely solely on the sftwr to alert them of any problems.. there have been some reports of Motor Failure, but again, the accuracy of is questionable at best, I believe it far more likely that in those cases it was ESC Failure due to Excessive Heat from the Batteries over time, these motors along with the ctrl sftwr are bullet proof, short of purposely jamming and then forcing current I don't think you can burn one up during normal operation, a seized bearing on the other hand is possible, but again, the nfo related to these Motor Failures are incomplete.. Only problem I've seen so far, that I believe is related to the Altitude Variance Fix is that the craft seems more squirrelly in Low-Light when landing, just be aware of it and fly cautiously..

..All of this I thought was Great.. One or actually TWO Less Things to Worry About.. So, just for grins I decided to remove v283 and reinstall v281 (v282 seems to have too many bugs i.e. video artifacts, apps crashes ..etc..) ..installed v281 and to my surprise I Did Not get my acceleration back.. Now That Smells an Awful lot like a BackDoor to the Firmware.. Like it or not, Believe it or not,, DJI wants their Product to be the best, they don't like people complaining about their product.. and by installing and running the sftwr or hrdwr you agree by way of the EULA to allow these changes.. so again, my advise is if you're craft is flying well and to your expectations beware of the UpDates and take measures to allow or deny The UpDates and their changes, bottom line.. you paid for it.. Oh! Almost forgot, the misspelled 'Spalsh' directory is still there hhaha.. (constantly Updating the Advertisement Nag Screen, via the PUSH srvc)..

  DJI-Go v2.8.4 (source APK-Pure)

Version: 2.8.4 (62) for Android 4.1+

Update on: Aug 22 2016

What's new:

- Added support for DJI Focus Handwheel.
- Added support for Facebook Live and RTMP live streaming.
- Added support for Coach Mode in DJI Lightbridge 2.
- Fixed the problem that iOS DJI Flight Records cannot be synced.

Version: 2.8.4 (63) for Android 4.1+

Update on: Aug 26 2016

What's new: (everything is the same, except for the build # ???)

- Added support for DJI Focus Handwheel.
- Added support for Facebook Live and RTMP live streaming.
- Added support for Coach Mode in DJI Lightbridge 2.
- Fixed the problem that iOS DJI Flight Records cannot be synced.

..Just in case it was missed in my rambling I want to say, I think the DJI Phantom 4 is the absolute Best of this generation drone currently on the market, and is most probable the drone (ctrl & reliability) the other mfg are trying to replicate.. its the Company and their practices that really sux..

..I thought I'd noticed more Signal Issues with DJI-Go v283 (using the GL300C) even though its difficult to tell while flying in town, the 2.4GHz band is so crowded, so on Sun.21Aug2016 I drove out to a place I'd been eye-balling on Google-Earth for some time.. No AirSpace Issues, Little or No Interference Issues, Plenty of Range to test and No Population to worry about.. the only issue, if it were to go down, it would be a nightmare or next to impossible to recover.., the Max Distance flown during this test was 11,125ft or 2.1mi, Take-Off Batt was @97%, after all Pre-Flight Checks Batt was @91% beginning the trek, it was obvious through-out the flight I had cross-winds.. I Landed with 21-22% Batt Remaining (11-12% actual useable Batt, mine shuts OFF @10%).. images heading out were pretty much into the sun, coming back images a lil better.. toward the bottom of this page are some of the images and video taken during that test-flight..


 
 

..UpDate Ultimatum..

..Update: welp.. DJi is at it again, 08Feb2017 (possibly sooner, this is when I found it) hadn't flown my Inspire in months due to battery issues and because I've been busy with the Phantom.. went out to fly and the App crashed while I was approx 180ft AGL and approx 1000ft dwn range, I was able to land safely.. I then attempted to fly another battery only to find DJI's Ultimatum.. UpDate or you can't use the App.. after several attempts was able to get the app to conn to the craft but was then unable to update the map.. few days later another flyer found a workaround to this ultimatum, but what was really telling about it was that once the workaround had been applied you were then presented with an option 'Remind Me Later' so what this tells me is that someone at DJi had decided !#$%^$ the Customers either they UpDate or they don't fly and argument could be made that the choice isn't whether you Fly or Not but whether you fly Safely because you could fly it just without a map.. I suppose the argument could then be made 'if you fly within the line of sight, you don't need a map' I disagree.. days later while flying my Phantom I noticed massive signal errors in an area that I've flown well over 60hrs.. I looked down at the map screen and I had flown off the map.. turned around, got back on the map and the signal issues cleared up, why? how? I don't know, this is what I observed, after landing I attempted to update the map via WiFi conn and it was then that my phantom (Ctrl-Sta, I use a separate tablet for each craft) was now infected with the Update Ultimatum Malware.. in my opinion its just another example of the sheer arrogance of DJi.. why another mfg doesn't take advantage of this is beyond me.. and BTW I've been flying DJi-Go v283 and aside from the obstacle avoidance issue, relatively problem free for >60hrs at this location, in addition to that I've been using the Original Firmware (v0101-0301) that was installed on the craft upon receipt, Jun2016..


 

 
   

 

 ..(above) this is a partial OverView of my Flights to Date on my Phantom4-01, Very rarely do I Land with <1.5min remaining battery power, more typically I land with approx 2min remaining With My Inspire1, however with the Phantom or more correctly the DJI-GO App (vs DJI-Pilot I use with the Inspire)  the Minutes Displayed on the Battery Level Indicator does not seem to Correlate well with the Actual Battery Percentage Remaining, this may be yet another intermittent issue or Bug, but I've been focused on the other issues (Primarily the Battery Over-Heat Issue) and will look into this issue more closely later.. that's certainly not to say that DJI will have a solution or even acknowledge any issue found, But, at least I will know more about the machine I'm operating.. This data is extracted from the Flight-Log(s) and is then Complied by Healthy-Drones (now called Air-Data)..

..(below) this is my equipment log for my Phantom4-01, All Data Generated including FlightLogs & Imaging are Backed Up to WD Ultra-Passport HD's & BD-R DL Disks..

 
 

 

   
  ..in the data above, Column, 'Internals Temp (ESC STBD)', I'm only guessing that the PC Board visible is the ESC, I don't know that for a fact.. (a decent manual would be nice)  
 

..I notified DJI of the Battery Temp Issue after my first flight, I then collected the data above as per Specific Request by DJI (i.e. use 'Hand-Held Temp Probe') and after getting back in contact with them and giving them access to the data they 1) didn't bother to look at it and 2) continued to tell me that there isn't a problem.. and this is after DJI told me that the Battery Operating Threshold is 60C (140F) ..I have initiated a Return/Replacement of this Battery.. the data clearly shows 1) its getting worse over time, 2) to keep within the DJI Specified Temperature Threshold I will continue to loose flight time, each flight.. the advertised Flight Time of the Phantom 4 is 28min, like MPG your mileage will vary.. hahha.. typical maximum flight-times, as you can see from the Healthy-Drones extracted data from over 2,000,000 Individual Flight-Logs is approx 20-22min.. UpDate: 30Jul2016, Received Replacement PH4-5350mAh-15.2V Battery from Vendor, 2wks from the day I sent the initial email, could've been a lil faster but all in all not too bad.. after explaining this issue, and the steps I took to get it the issue resolved (i.e. Defective Batt Replaced) to the other Customers, I was Banned from DJI's forum, that ban is Still in place >6months later..

UpDate: May-Jun2017 Now each of my Batts have approx 120charges, and I notice that the op temp is starting to rise even with ambient temps <80F.. seems that as the batt age the  internal resistance increases thereby generating more heat.. Aug2017 Batt#03, 132charges, ambient temp approx 93F (33C), op temp 150.7F (65.9C)  with an 18min flight time.. Sept2017, Batt#01, 137charges, ambient temp approx 68F (20C), op temp 132.4F (55.7C) with 17min flight time..


 

..Remote Ctrl Battery..

..I bought the P4 with 2 extra batteries, not long after I purchased a spare Rem Ctrl in case of catastrophic failure of the remote, loss or breakage.. my best guess is that at approx 100charges on the rem ctrl the battery started loosing capacity and it went down hill quick.. in the beginning a single flight would use approx 5-7% of the remote ctrl batt capacity.. that then increased to 8-10%.. then 10-15%.. then as much as 25%.. I treated this battery like I've treated all my rechargeable batteries, but I thought for whatever reason this one has failed prematurely.. I then found out there isn't a direct replacement and that DJi recommends purchasing a New Remote Control..! WTF!?!.. well by this time I owned a total of 5 remote ctrl's between the Inspires and the Phantom.. Figured I'll swap out one of the batteries and be back up running in no time.. Wrong..  I started swapping out the batteries and found that 'This' remote control would not charge 'Any' of the other batteries greater than 50%, then 20%, then 2% and finally 1%.. I then took that same battery, installed it into the new spare rem ctrl and as if by fMagic it charged to 100% ..as it turns out,  the Remote Ctrl itself has a limited charge capacity or a limited number of times that it will charge its battery to 100%.. at the risk of sounding like whatever I'll just say that I am intimately familiar with manufacturing and designed obsolescence, but this has got to be an all time fLow.. 185$ 7.4Vdc 6000mAh 2S1P Battery Replacement.. I then calculated the total cost of owning and operating this P4 and this point in time to be 15$/hr, ..if I add up all DJi products including spare parts that number goes up to 61$/hr.. Below you'll see my Antenna and RF Booster Mod, my original design included a battery slung up underneath.. but wanting to keep the overall foot-print and weight to a minimum I changed it.. now with this rem ctrl batt charging issue in mind I've decided to revisit that design, to basically increase (double) the overall capacity which will thereby decrease the number of charges required from the rem ctrl..


 

..Dropped Connection & RTH..

..04Sept2016, flying down at the harbor interference is intermittent, sometimes I fly there and have Zero Issues, on two occasions I've actually Dropped-Connection with the craft due to interference (and only Once has the craft actually initiated a RTH and that was while testing Chl20), on 04Sept2016 while flying I first noticed the interference with the Video DwnLink, it became Choppy and had excessive artifacts so I watched the Signal Indicators in DJI-Go Very Closely, the RemCtrl Indicator Remained @100% (the idiotic 'Bars' remained Full) while the HD or Video Signal Indicator was intermittent, But never dropped below 2 Bars.. so I continued to fly, made a fly-by and the signal seemed to clear up.. so I took it out to approx 4500ft at approx 300ft/agl in a diff direction, made my turn towards Home-Point, could in fact see Home-Point and within a few hundred feet complete loss of signal, Grey-Screen, RED Indicator on the RC and the DJI-Go App just locked up in that state.. I purposely set Home-Point and Verify RTH Settings (Altitude & Function) everytime I take-off whether I get the (Auto Set) Audible Notification (also intermittent) or Not.. so I waited for it to fly itself back home.. I know now I waited too long, by approx 90sec, nevertheless that's what I did.. still nothing, so I shut-dwn the DJI-Go App and reStarted it.. it immediately reConnected and Set what I now call the 'Auto-Set Home-Point' (my Batt was @26% at this point) ..the Auto-Set Home-Point with my Phantom4 running DJI-Go v283 is ALWAYS the AirCrafts Current Position, which in this case or at this point was approx 3000ft dwn range (btw the last 1000ft of that 3000ft is a body of water)..

..The 'Auto-Set Home-Point' again is ALWAYS set at the AirCrafts Current Position, when: 1) The Motors are Started, or 2) When DJI-Go ReConnects to a Currently Running Craft.. so, what I can assume from this situation is, the interference was so bad that it caused a Dropped-Connection with the RC/Ctrl-Sta and was Bad Enough to wigg-out the compass, that's the reason it didn't RTH and instead just hovered in place.. All Good, I don't think so.. I think the Craft should be smart enough to remember the Home-Point Set at the Start of the Flight.. it can remember, Video Settings, it can remember RTH Altitude and it can Remember these things even if you UnInstall the App and ReInstall and Diff version.. so these things are remembered or 'Stored' on the Craft itself.. Obviously it has to have a properly functioning Compass to return (RTH) to the Stored Location..  ..So my procedure from now on is this, If I drop Connection with the Craft, I'll wait no more than 30sec for it to re-conn before I Shut-Dwn & reStart the App, once the App has reStarted and I've Verified Connection and Ctrl the next thing I'll do is Set the RC/Ctrl-Sta as Home-Point and proceed to fly back, at this point all you can do is hope everything works as it should.. if it were to drop connection again and I cannot reConn to it, it should return to Me (the RC/Ctrl-Sta) rather than turn around and go back to the New Home-Point that was set upon reConn.. ..images of the flight path and some of the data of this flight are just below this column.. (Click to Enlarge)

..the next day I took it to a land-locked location to do some testing and verified 'Auto-Set Home-Point' is Always Set as the
'AirCrafts Current Position' 1) Once the Software has initialized and/or Motors are Started, or, 2) Once DJI-Go RE-CONNECTS to an already running AirCraft.. and this is the same for DJI-Go v281 and v283, I Did Not test v282 because it seems to be toooo Buggy.. as far as I know this could just be the nature of the beast.. But I can confirm that this characteristic is No Where in the Manual.. Also, with my P4 once RTH has been initiated the Craft ascends to 1/2 the RTH Preset Altitude, it then Adj's Heading, ascends to the Preset Altitude and Returns to the Home-Point in Sport-Mode.. so be aware of it because once it reaches Home-Point it will come Down Very Fast.. ALSO Not in the Manual..

..IF on the other hand you'd rather set the RC/Ctrl-Sta as the Home-Point you can only set it AFTER the Motors have Started (also not in the Manual), remember IF the Ctrl's and the Craft are operating normally, then, the Home-Point will be reset to the AirCrafts current position Once the Motors Start, Sftwr Init or ReConn to am already running aircraft.. 'IF' it doesn't and/or is Intermittent, Un-Install the App, PWR-OFF the Device, wait 30sec, PWR-ON and Re-Install the App, I suggest the site APK-Pure ( https://apkpure.com/dji-go/dji.pilot ) , they usually keep the last 10 versions of DJI-Go, DwnLd your version and keep a copy of it on your device.. if the App seems to be acting up or you see some strange anomalies Dump it and re-Install, it only takes a coupla minutes to rule it out..


 
  ..Signal Issues incl Flight Path(s)..  
   
 

..the graphic above depicts the Flight-Path included with the Signal Errors, Grn being little to no errors thru Org, Red & Pur being the worse signal error.. obviously there's more to it than just the errors themselves because during this flight the signal errors were GRN (little to none) when the lights went out, the other problem is, this graphical data doesn't differentiate between the Video DwnLink Signal and the Ctrl Signal, also Important and Not Displayed is the Interference to the Compass, why the Ctrl-Sta (DJI-Go App) just fell on its face in this situation is a question for DJI, and knowing DJI that's a question that'll never get answered.. (BTW the RED Path, is approx 560ft that the P4 Coasted to a Stop or the time / distance  traveled before the  Phantom finally decided it couldn't find its way back home, gave up then just hovered in place.. i.e. Last-Known to ReConn Location) (Click to Enlarge Anim-GIF)..


 
..Antenna Testing & Mod..

    ..After the dropped signal issue described above I decided to do the 'Antenna Mod' it was then that I found the performance of the antenna's on the market were less than desirable and far from reliable, so I decided to do the research and design my own..

 ..On EBay, Amazon, BangGood or Other Drone/UAV WebSites you can find antenna deals from just 99¢ to 88+$ each, I've purchased hand fulls of of the cheaper antennas prior to buying the test equip and basically used a trial and error approach to finding a half-decent antenna(s) and believe it or not the 20$ antenna(s) do not perform 20x, or even 2x better than the 99¢ or as it turns out than the 88$ antennas, and in some cases barely any better at all.. they're simply not well tuned to the applicable frequencies and BTW ridiculously high Gain is no substitute for a well tuned, impedance matched antenna.. I bought an antenna set on EBay, 20$, very popular in fact and at first glance I had high hopes, nice lil patch antenna.. but at any distance  the performance just fell off and it seemed to pick up interference as if it were a coat-hanger wrapped in tin-foil or a mosquito net, everything flying it caught.. it came with cables and a small screw-driver, also the RP-SMA Conn on the antenna was of very poor quality.. the Gain is listed as 2.4-2.6G hhaha and so is the frequency..! I actually bought them for the 'Mod-Cables with 90 Connections' the 2nd set I bought they had re-designed the innards which did help, the original was tuned at approx 2360MHz (v2 approx 2490MHz).. when I emailed them they told me '..you need to install the DJI-Go Patch..' the patch referred to is the 'Channel Patch', as I remember added chl21-chl32 which would push it even further from their 2360MHz tuning and in fact would push it into the 2500MHz 'Licensed Band', precisely the reason I believe that particular Mod dried up.. So, you've made the antenna mod, now you need a decent antenna.. short of purchasing the equip & designing and/or tuning one yourself, go to EBay and buy a hand-full of cheap antennas take your drone to an area of known high interference and test it, I suggest your testing is not done over moving traffic or people, the safest (from a personal injury stand-point) I think is over water.. get a free acct on Healthy-Drones and document your results.. (caveat: ..signal errors on HD is Not the whole story, actually far from it, but it is better than nothing.. for example, I've flown and gotten the RED Indicator "Weak Tx Signal' but the Signal Errors on HD showed no issues, other times I've had what I thought was a perfect flight No signal issues what so ever but yet HD signal errors were thru the roof.. I do not mean to berate the HD service, it is currently the best out there, but the algorithms used are not flawless)..

  ..as it turns out RF technology is Very Interesting, but, Testing can get Very Expensive.. to date I'm Tuning my current antenna design and again to date, my antenna is Magnitudes more resonate at the applicable frequency band used by the Phantom(x) and Inspire(x) than is the typical antenna avail on the market, that includes the antenna(s) supposedly designed for those drones.. as they say.. proof is in the pudding, data & specs forthcoming.. Not only is my antenna better tuned but has a VSWR of approx 1.03-1.20:1,  (in fact at least 1 variation of my design has a VSWR of  1.01 which is ≥-46.064dB mine is -49.5dB, 1.0:1 is Ideal.. to date I've tested over 420ea variations)  typically the antennas sold online don't offer any performance specs, most usually only give the Gain.. but when they do their VSWR is usually listed as ≤2.0  and BTW some of the absolute worst antenna I've purchased & tested still have a ≤2.0:1 VSWR.. Others do give a Horz & Vert graphic depiction of the simulated radiation patterns, which gives you some idea of the Gain and/or Beam-Widths (Gain is a relative measure of the antennas Directivity, usually expressed as dBi.. dB relative to a theoretical Isotropic Radiator) depending on the Type of antenna, which is good nfo, however I think the more important spec is the Band-Width and of course the VSWR..

  ..Very Basically the VSWR (viz-war) property of an antenna is the ratio of the antennas ability to radiate the source energy vs having that energy reflected back to the source, obviously the better (lower ratio) the greater its ability to transmit/radiate the source energy and is an indication of its tuning or resonance.. if you Tx/Rx at say btwn 2410-2420MHz and your antenna is a so called Wide-Band thats sloppily tuned with a huge 100MHz dip or Bow across the entire 2400-2500MHz band, then yes, that antenna will Tx/Rx your 2410-2420MHz signal, however, it will also pick up alot of unnecessary frequencies which in this case or for our purposes amounts to Interference, and again will typically be very inefficient, ..since the whole reason for an antenna is to transmit and/or receive signal, the VSWR could also be considered a quantitative measure of its efficiency i.e. VSWR of 1.15:1 = 99.5%..  also if due to its inefficiency (poor impedance matching) the reflected energy or the power is high enough it could damage the transmitter.. simply adding amps/boosters is ridiculous and actually unsafe, harmful, yeah you might be able to push enough energy thru a poor antenna to get 4mi range, but is it worth getting Cataracts..? or putting your brain in DeFrost Mode..?   I am not an RF Engineer, and one could probably pick apart my very basic description here (impedance matching, reflection coefficient yada yada)..

  ..Some sources of interference are obvious and you can usually see the effects of it at the Ctrl-Sta.. it may present with choppy video (more correctly Pixelated Video, Choppy could also be indication of poor tablet performance) or Pink/Purple Banding.. On my ctrl I've found that using channels above Chl15 were highly susceptible to EMF from High-Voltage Panels & Under-Ground wiring and if the area has high galvanic corrosion and the ground was wet the interference went thru the roof.. and BTW that includes interference to the Compass  i.e. Pink/Purple Banding, Compass Interference av >100 (at the harbor, near the docks).. in my testing with both the Inspire & Phantom I've found that Chl14 was in general the best or most clear of interference  from EMF and random WiFi or more correctly random 2400-2500MHz signal/energy, we're literally bathed in it, for instance most of the Microwave Ovens I've tested operate at approx 2440-2460Mhz (approx chl17-18) and emit a surprising high amount of energy in comparison to the drone ctrl.. and yet another source of interference are Obstructions, when you think of an obstruction you think of the signal actually being blocked, but thats not the whole story, obstructions also create interference when they are within the 'Fresnel Zone'  (see https://en.wikipedia.org/wiki/Fresnel_zone (see also Multi-Path Propagation and/or Interference).. in ref to the ctrl or the Receiver itself, most of these circuits are designed to filter out frequencies that aren't used so as not to overwhelm the circuit, but if you've flown either of these drones for any period of time you'll know that more filtering so to speak is needed, the 2.4GHz band is just too crowded and the ctrl seems very sensitive to interference, and with this interference we're not talking about a drop in xfer rate, lost packets or an occasional corrupted file (not to diminish the importance of good Video DwnLink) but the real possibility of loosing the drone..

UHF Ultra high frequency TV broadcasts, microwave ovens, mobile phones, wireless LAN, Bluetooth, GPS, and Two-Way Radios

2400.0 2417.0 This band is used in the Amateur Radio Service. Operation of unlicensed Part 15 Devices is permitted between 2400 and 2417 MHz.
2417.0 2450.0 This band is used in the Amateur Radio Service. This band is allocated for both Federal and Non-Federal use. Operation of unlicensed Part 15 Devices is permitted between 2417 and 2450 MHz.
2450.0 2483.5 This band is used in the Fixed Microwave Service, the Industrial, Scientific and Medical Equipment Service (ISM), the Local Television Transmission Service, the Radiolocation Service, the Public Safety Radio Service, and the TV Broadcast Auxiliary Service. Operation of unlicensed Part 15 Devices is permitted between 2450 and 2483.5 MHz.   (FCC)

  ..Another problem with our ctrl is ESD (Electro-Static Discharge) touch the antennas while operating the drone as little as possible, ..on a Mod'd Ctrl the Chrome Scussion or Trim at the base of the antenna is a direct circuit to ground, unless of course you've taken measures to isolate or remove it, keep this in mind while operating your craft.. a few other things to keep in mind with a modified ctrl  1) never Power up the ctrl without an antenna or load attached  2) terminate the connections with a 50 terminator, the Receiver, while facing the ctrl in the operating position is the Right-Hand Connection, it will always pickup signals even in the OFF position.. so either keep a load/antenna attached or terminate it  3) SMA connections are relatively fragile, particularly the SMA-Female or RP-SMA Male, repeated conn cycles will wear and/or damage the conn, best practice is to use a sacrificial connector, the typical Quality SMA type connector has a Loss of approx 0.3dB (each), caveat, you get what you pay for in this world, keep that in mind when purchasing your connections, terminators or cable.. (50, 6GHz, SMA Terminator, Good Price @Amazon---> http://tinyurl.com/jxg9krs )

  Remote Control(s) RF Power (Listed as EIRP in Specs)

 - GL658A (Inspire1):   Dual-Band 2.4 / 5.8GHz   20 / 13dBm (FCC), Not Listed (CE)
 - GL6D10A (Inspire2):    Dual-Band 2.4 / 5.8GHz    26 / 28dBm (FCC), 17 / 14dBm (CE)
 - GL300C (Phantom4):   2.400-2.483GHz    23dBm (FCC), 17dBm (CE)
 - GL300E/F (Phantom4pro):    Dual-Band 2.4 / 5.8GHz    26 / 28dBm (FCC), 17 / 14dBm (CE)

..Note: EIRP: Equivalent Isotropically Radiated Power, is a relative measurement of output power based on a theoretical single point source radiator.. the formula is   P-L+G   (TxPwr - CableLosses (incl conn's) + AntennaGain = EIRP)..

Remote Control(s) RF Power Ratings as per FCC Compliance Application(s) (Listed as Conducted PWR)

 - GL658A (Inspire1):   SS3-GL6581410  -  2.4GHz  370mW
 - GL6D10A (Inspire2):    SS3-GL6D10A1609 - 2.4 / 5.8GHz  834 / 566mW  /  240 / 145mW
 - GL300C (Phantom4):   SS3-GL3001510 - 2.4GHz  303mW
 - GL300E/F (Phantom4pro):   
SS3-GL300E1609 / SS3-GL300F1609 - 2.4 / 5.8GHz  112 / 693mW  /  175mW

..Note: Output Power Listed as Conducted: Conducted Output Power is defined as the total transmit power delivered to all antennas and antenna elements averaged across all symbols in the signaling alphabet when the transmitter is operating at its maximum power control level (FCC 15.247(b) (3))..

Aircraft RF Power Ratings

 - Inspire1:   SS3-WM6101410 - Incomplete
 
- Inspire1-v2:   SS3-WM6101510 - Incomplete
 - Inspire2:   
SS3-T650A1609 - Incomplete
 - Phantom4:   2AHAY-WM3301601
- Incomplete
 - Phantom4pro:   
SS3-WM331A1609 - Incomplete

   ..The purpose of my Antenna design is not just to give range because after all the stock remote with stock antenna's can take the Phantom or Inspire further than the battery can bring you back in an 'Unobstructed and Interference Free' area, the purpose of my design is to Radiate (Tx) (and Receive, Rx) as much of the Signal Energy as is Available, within the Applicable Freq Band, To the Drone, when operating in High-Interference Areas i.e. Near Towers, for High-Tension Line Inspections or over Heavily WiFi Congested Areas etc..

  ..Below are a few of screen shots, I won't give too much information at this time, primarily because I may offer my antenna for sale at some point (recoup some of my costs for the testing equip) and because I'm still in the Tuning/Testing Stage..  but Stay 'Tuned'..

 

..this is the Return-Loss data of my proto-type, as you can see it is very much resonate at almost dead-center of chl14, This is what you want, this is an example of Properly Tuned, Impedance Matched Antenna, this Antenna will Transmit & Receive 100% of the Avail PWR, This Antenna will shine as bright as the Star Sirius through a fog of WiFi Interference..



  ..this particular system is equipped with Sunhans SHRC24G3WP Signal Boosters, with hard connections, in an inline configuration.. no excess wires or connections.. the connections from the booster housing are the more durable, or less fragile RP-SMA Female making the external connections between (the Rem-Ctrl and Antenna) sacrificial.. the signal booster properties are as follows: Output PWR 35dBm, Transmit Gain 15-18dBm, Receive Gain ≤12dBm, PWR Supply is a removable 7.4vDc 2500mAh Battery with a 25C rating.. with a current load of ≤600mAh that gives this system several hours of operation btwn charges while still holding the overall foot-print and weight to a minimum, the weight added is only 17.5oz with the Battery & Antenna installed.. the device itself can be installed, removed and/or dis-assembled in 2min or less, and with a lil practice as quickly as 30sec.. it was produced using PLA on a 3D-Printer again making it plenty durable and light, total print time for the 4ea parts is approx 12hrs..  in this current version it has a 3digit LED battery voltage indicator,  the next version will include a battery capacity indicator that can be upgraded by simply removing and snapping into place the new battery compartment lid.. Anyone interested in purchasing this system in Kit-Form or as a Complete System (i.e. Amps, Connections, Battery, Antenna ..etc) can contact me via the Inspire/Phantom Pilots Forum or via email   SAS (at) GasRecovery (dot) net  ..and BTW once the new battery indicators come in I'll ship that to you as a free upgrade.. also please specify Trim Accent Color Options (incl LED indicator) i.e. Red, Green, Blue, Yellow, Silver, Black or All White  (PETG vs PLA also avail).. your Logo or Insignia can be added but must be provided in SVG format..

 

 

  ..Return Loss examples of typical antenna sold online..

 
..these are the Return Loss data from a sampling of antennas I have tested, they are not the worse picks, they were picked at random.. if I were to give the Mfg name of these you would undoubtedly recognize them, I'm providing them here as a FYI, when you decide to send your 1500-2000+$ drone a couple hundred feet AGL a good (communication link) antenna is very important.. think of them like this: the few that are sloppily tuned within the 2400MHz band are out of focus or out of Tune (Focus is more related to the Gain property of the antenna), the others are more in Tune to frequencies that are not applicable for the Phantom or Inspire Drones.. (BTW #01, the best of the 6, is the 99¢ Rubber-Duck 5dBi antenna and in fact last time I looked they were down to 89¢/ea problem is, this was the best of 10ea that I bought)..

Click Images to Enlarge

..the images above are the spectrum analysis of the Phantom4 & Inspire1 craft(s) using their respective rem-crtl's.. RED in the UPR Graph is random WiFi  Interference at the time of testing, BTW testing was done in the same environment, minutes apart for both craft, colors in LWR Graph basically depict levels of signal amplitude over time, the length is just the time it took to chg channels (Chl13-20), wanted to get them all on one graph..


 

..P4 Prop & Prop-Lock Wear Indicators  (DJI CP.PT.000360 Phantom4 9450S Quik Release propellers)

 

..at approx 40hrs flight-time I started noticing indications of wear on the bottom of the props, the wear is actually the rubbing or marring of the plastic by the tension spring, and is caused by wear of the prop lock allowing the prop to cycle back and forth against the tension spring, obviously the marring itself isn't an issue however the slop or clearance btwn the prop-lock and the prop is.. the more clearance or slop the greater the chance for shear.. I swapped out the props and the prop-locks and took some measurements.. the dimension of the locking tab on the New Prop-Lock was approx 0.147'' (3.75mm) and on the 45hr Used Prop-Locks was approx 0.140'' to 0.143'' (3.57-3.60mm), I was unable to get an accurate measurement of the internals of the prop itself.. they do in fact fit snuggly on the new prop-locks however the fatigue of those internals is the other variable that should not be forgotten.. the risk vs cost of the props.. I replaced them.. also worth mentioning is I fly my P4 as safe as possible, I make No Abrupt Changes in Heading or Speed, if you do fly like this, you may very well see these wear indications much sooner.. I have recently flown in rather Gusty Wind Conditions causing the craft to make abrupt changes to compensate which will also increase the wear to the Props & Prop-Locks, just another variable to keep in mind.. Now on my 2nd Set of Props approaching the 40hr mark I began to notice a 'Knocking' when I started the motors, it was subtle, but unmistakable.. Again rather than risk the craft I replaced the props and locks, this time found very apparent wear to the prop locks, see fig#04..

 
 
 

..P4 LWR Shell-Fuselage Crack

 

  ..Rec'vd this P4 29Jun2016, at flight# 362 approx 106.5hrs, I found a Crack (fig#01) emanating from the battery bay opening towards the Left-Rear Landing Skid.. I've NEVER Crashed this craft, never so much as a hard landing, I use a landing pad and land within 1.0'' of my takeoff point 99.9% of the time (I've got 362 flight-logs incl the HiRES & LoRES videos to prove it), I do not carry, lift or move this craft via the landing skids or the struts, and I do not slam the battery into place.. 11Mar2017, at flight#390 approx 115.5hrs, I found Another Crack (fig#2 & 4) on the right side, emanating from the battery bay in almost the exact same spot as the left side.. I now believe this to be a weakness in the structural design rather than a defect in the plastic..  I would have thought the Craft would out live the Batteries (without having to patch it up like Frankenstein that is, even though all 3 batteries have heat cracks at the charge indicators and on the side at the die marks).. Fig#03 is an area of concern, it has not yet developed into a crack and may in fact just be a die mark, but I will keep a close eye on it..

 
 
 
 
   
   
   

 

Click Images to Enlarge

 

 ---   DJI Phantom 4  - Video & Images
 
 

..27Mar2017..

..12Jan2017..

..13Oct2016..

 ..Started Raining But Couldn't Resist..

 

 ..Sunset from Deep-Creek Harbor, 29Aug2016...

 

---   Ragged Island, 21Aug2016  (Max Distance this Flight 11,125ft, with Stock Remote)