DRONE MECHANIC

Who's your drone mechanic? Surprise -Its you!
 

1) Tools you'll need:

      #O  Phillips head screwdriver
      Dental pick
      Electricians black tape
      Superglue
      Hemostat - small 3" or so.
      Single edged razor blade or x-acto knife
      VOM (volt-ohm-meter)
      Finger nail clippers or small wire cutters
      Soldering iron 15-30 watts*
      Rosin core solder*
      Heat shrink tubing - various sizes*

      Nail file (diamond dust) Forget the sandpaper 
      or cut steel files. They are worthless.

      * Internal repair work

THINGS TO DO

Cracking spars. Most small quads are made of plastic. Some have limited use of carbon fiber or what appears to be carbon fiber parts or materials. The spars are the shafts that supports the motor/rotor assembly. The spars are quite small, about .170" or 4.3 mm square. 

Pretty tough. But there is a small problem. The UDI design uses extremely small screws at two places to attach the spar to the chassis of the quad and to the motor assemblies.

The holes made by the self-tapping screw starts a stress point and the constant crashing and subsequent twisting of the spar can cause it to crack lengthwise starting at the screw hole. I recently replaced (2) cracked spars.

It happenned at about 15 flight hours on the quad. Now I inspect the spars on a regular basis. Every week or so. Even cracked, the spars held up okay. You can superglue the crack or use black electricians tape as a temporary reinforcement.

THINGS TO FIX
Bent rotors. If the bend is only a small amount (generally not very noticeable except for vibration), it's okay just to bend it back into the correct position. 

I use the inside center of the UDI U818A's body shell as a reference point turning the rotor so that both rotor ends can be compared to the same reference point.

Hold the rotor with one hand near the center of the rotor, and bend the rotor slightly up or down with your other hand. Don't pull up on the tip. If you can see the bent area of the rotor, try to re-bend it there.

If you not sure you can do this, while at home, use a #0 phillips screwdriver to remove the rotor set screw and remove and bend the rotor off while it's off the quad. Don't loose the screw! It's really, really, REALLY - small! Rotate to the other blade (opposite side) and compare after assembly.

The should be at the same height as referenced to the body shell. Try get within a 1/16" or less. Both rotor blades should be 90 degrees to the rotor shaft. Compare to an unbent rotor. Not sure? Replace the rotor with a spare. You do have spares, right?

DRIVE GEARS BINDING

It happens. You land hard, so you decide to test the rotors gears to see if they are damaged. The sound of the rotors is "strange".

Clicking? Buzzing? One of the rotors A) spins and then stops or B) won't spin at all or C) clicks while it spins. You suspect there is a speck of dirt on the large gear.

You look for it.  You can't see anything. Hmm? You rotate the rotor the other direction and it always stops at the same place. That's where the dirt is. It's causing the two gears to bind.

You use a small magnifying glass or cheap magnifying glasses. Yes, there it is. It's soooooooo small.Using your dental pick, you clean the grooves of the large gear. 

Then flip the rotor with your finger. It goes past 360 degrees - no clicking noise. Smooooth :)  You put it on the ground and work the throttle - all the rotors spin normally. Congratulations - your a drone mechanic!

BATTERY EJECTS ON HARD LANDING

Oops :)  Easy fix - a couple of turn of black electrical tape to make it fit snug.

BATTERY, AZIZ!**
Battery charging. Do it right after flying. Don't forget :)

LOG BOOKS

Keep track of flight hour/problem/weather/etc. Use the link here if you don't the heavy math :)  Enter start and stop time of the flying session. The calculator gives you the elapsed time. Enter it in you log book. 

Elapsed Time Calculator 

Use this second link to add all the page entries for a total page time. Enter in the appropriate place. Done with this page? Use the calculator to add the previous page's total to the current filled page total. Easy.

Add All The Page entries 

BATTERY CONNECTORS
Fit too tightly? Use the diamond file. File a very small amount at one time, check fit - repeat. Better to have to do several attempts at filing that to take off too much. Also useful for the fingernails :)

KEEP ON FLYING

** From "TRUE LIES" - the Movie!

CHARGING MULTIPLE BATTERIES

I charge 15-20 batteries at a time. Here's how.

SORT THE BATTERIES

Read the voltage of all used batteries with a voltmeter. Sort the batteries into one of 3 piles:

     First pile:       3.69 Volts or less

     Second pile:  3.7 to 3.79 Volts

     Third pile:      3.8 Volts or more

The bulk of the batteries I charge are in the second pile of 3.7 - 3.79 Volts. This is because I fly for 6 minutes per battery, timed, and then stop flying and change battery at 6 minutes. This leaves about a 15% remaining charge in the battery. 

Yes, I know. The UDI manual says, "6 to 9" minutes flying time. However, at 9 minutes the batteries would probably be at or below the critical voltage of 3.209V. I choose to use more batteries and for a shorter length of time. 

Remember, these are 1C batteries. 1C means they can ONLY be charged at the rate shown on the battery and NOT at a higher rate. All my batteries say 600 mAh. The maximum charge rate is 600 mAh.

     When multiple batteries are in parallel, the maximum rate of
     all batteries works out to the same 600 mAh per battery as the
     charge load is "spread out" over multiple batteries.

CABLE TO QUICK READ BATTERIES

Get a volt-ohm-meter (VOM). About $10.00-$15.00. Harbor Freight, Lowes, Amazon, eBay, etc. Set scale to the next step higher than the battery voltage to be read.

I use the 20 VDC scale. VDC means: Volts, Direct Current. All batteries are DC or direct current. Don't use AC scale. Readings will be incorrect if you do. See picture below for custom adapter cable. Click on pic for larger view.

 

I made mine from:

     1) 1 each 12" long jumper cable with alligator clips on each end.

     2) Cut this cable in half.

     3) Solder each half of the cable to a scavenged JST female plug with wires. I got mine off an damaged quad. Note the silver dot on the JST. All my batteries are "indexed" in this fashion. See other posts for more information. 

Prior to soldering, I inserted two 1" length of heat shrink (HS) tubing. After soldering, I positioned the HS and shrunk them with a cigarette lighter flame.

     4) Add some electricians tape to HS connections to "beef it up". I slipped on a larger piece of HS tubing and shrunk it into place.

     5) Clip the alligator clips to the red and black leads of the VOM. Ignore polarity for now. Set VOM to 20 VDC or next highest setting above 3.7 volts. 

Note: My meter (above) has a black triangle inked on the meter's side just opposite of the 20 VDC setting. Insert a battery into the JST fitting.

     6) Read voltage on meter. If you see a minus (-) sign (see pic above), the cables are hooked up incorrectly. Swap the red/black leads. Meter should now read voltage with NO minus sign.

Polarity is now correct. VOMs will read DC voltage with cables reversed or normal. If the leads are reversed, the (-) or negative sign shows up.

     7) Add a 1 inch piece of Black electricians tape to the black lead of the VOM. See picture. The black lead is always ground or negative or minus (-). The BLACK tape alligator clip now goes to the negative jack of the VOM.

ATTACH BATTERIES TO THE 5-WAY

You can attach up to 5X batteries one a 5-way cable. Here's a seller with 5X 600 mAh batteries and a free 5-way cable on Amazon. The battery/connectors fit the UDI U818A:

5-WAY CHARGER CABLE

Here's a seller that sells only the cable. It also fits the UDI U818A:

ANOTHER CABLE, NO BATTS

Use one charger for each 5 way cable. I have 3X 5-way cables and 3X chargers. All identical.

B6 LiPo DC CHARGER

I use these:

B6 LiPo CHARGER 

I use an AC adapter (wall wart) with output voltage of 12 volts (12-18V is ok) and with an output current of 2 Amps, minimum. Here's what I bought: 

B6 LiPo Power Supply

Be sure the plug diameter on the end is 5.5mm with a 2.5mm center positive (+). The above adapter meets these specifications.  One of my B6 chargers came with a 5.5mm x 2.1 center. The above adapter will fit both.

CABLES

Locate in the "Banana plug" cable in the charger box.  Banana plugs have a gold plated fluted spring connectors on one end and "T" shaped male plug on the other. This cable is about 12" long.

The above pic (click for larger) shows 1 battery on the cable end. Substitute the 5-way cable to charge 5 batteries. Locate the JST / "T" shaped female jack cable (about 5" long) and plug it into the Banana cable.

You now have a cable setup to be plugged into the charger that has a JST jack at the end. Don't plug in the cable, yet.

LOAD THE 5-WAY

Load 5X LiPo batteries onto each of the 5-way cable(s) taking only the batteries from the same pile. Do not load other batteries of different voltages from the other 2 piles. Single batteries are charged individually.

After I load all the 5-way cable, I charge the remaining odd batteries, individually. That leaves 30 minutes or so for the batteries on the 5-way cable(s) to equalize their individual voltages somewhat.

CALCULATING TOTAL AMPERAGE

All batteries should be the same or near same mAh setting. All mine are 600 mAh. Charging 5X at a time, you multiple the number of batteries to be charged on the 5-way by their individual mAh to arrive at the total maximum allowable  current (amperage) to be used during the charging process.

You are charging in parallel so the LiPo voltage of 3.7 VDC +/-  is near the same for all and the total current allowable is the sum of all the batteries mAh to be charged.

You CAN use less than the total maximum calculated amperage if you like. But, NOT more! Charging will take correspondingly longer with lower charging current.

TOTAL MAXIMUM CALCULATED EXAMPLES:

      
   5X 600 mAh = 3,000 mAh or 3.0 Amps & does 5 batteries.

   4X 600 mAh = 2,400 mAh or 2.4 Amps & does 4 batteries.

   3X 600 mAh = 1,800 mAh or 1.8 Amps & does 3 batteries.

   2X 600 mAh = 1,200 mAh or 1.2 Amps & does 2 batteries.

   1X 600 mAh =    600 mAh or   .6 Amp & does 1 battery.

PLUG IN SETUP CABLE

Red plug goes into Red jack, Black plug goes into Black jack. Double check! You now have a cable plugged into the charger that has a JST jack at the end. Charger cabling is now setup, but 5-way batteries are NOT connected at this time.

POWER UP

Plug the power supply into the charger. Then plug the power supply into the wall. The charger will power up and display a message. Following the printed directions in the charger manual.

SHORT SETUP VERSION

The display should say "LiPo CHARGE" or "LiPo Fast Charge". If it doesn't, follow the manual and set it to " LiPo CHARGE" or "LiPo Fast Charge". Then press START button, once. The AMPS setting will now flash.

The next 2 buttons to the right are the "setting up" and "setting down" buttons.  Press INC or DEC until it says 3.0A. Then press 
START. That will set the AMPS.

AMPS will now flash at 3.0A. Press START. AUTO may/will now flash. Press START. If nothing flashes this indicates charger is set to charge. You are now set up for charging. 

Connect the 5-way cable with the batteries - now.

The reason for putting the batteries in last is if you make a mistake programming the charger, you will not charge at the wrong settings. The button pressing sequence is not complicated but you will need a little practice to learn how to make the selections using the 4 buttons.

CHECK AND START CHARGER

To start the charging sequence, press START and hold for 3 seconds. The words "BATTERY CHECK WAIT..." will appear. 

If the charger is set to AUTO, it will check the cell voltage of the battery and if all is correct it will start the charger.

If no autostart (AUTO) shows, look at display. You should see 2 of these: 1SEL.

If there are 2 sets of xSEL numbers, both must be (2) identical. Example: battery is detected as 1SEL and charger is set to 1SEL. This is correct. The charger sees any number of cells on the 5-way cable as one cell or 1SEL. 

This is because the batteries are in parallel. The charger may or may not show more than 1SEL. There are at least 2 models of the B6 charger. See your manual.

I have one charger that only shows 1SEL (once) and also shows the word,  "AUTO". I have another charger that shows 2x 1SELs and no AUTO. This charger MUST be started manually by pressing the START button.

Just be sure you are charging a 1SEL or single cell battery. Again, the 5-way with 1 to 5 batteries is "seen" as a single sell or 1SEL.

If you see 1SEL and 2 SEL or 3 SEL on the same screen - something is wrong. Disconnect the batterie(s) and start over. When there are 2x 1SELs, or 1x 1SEL and AUTO, the charger can be started. 

If in AUTO mode, the battery will do this checking automatically and start the charger for you. Any questions? Consult your manual.

NOTE

I have 3X chargers. One acts slightly different than the other 2. Most likely due to a slightly different operating system. All do the same thing.

All chargers shut off automatically at 4.2V which is maximum allowed voltage for LiPo batteries. I don't use "fast charge" as sometimes it will shut off early (4.17 volts) if the batterie(s) are near full capacity when put on the charger.

KEEP ON FLYING!

UDI-U818A MODIFICATIONS Part 1

1) REMOVING EXTRANEOUS STUFF

The cover has 4 attach points.  To remove the top cover push aside the plastic tabs, doing one arm at a time. When all 4 are loose, peel up the white tape holding down the wires going to the front LED.

Remove the cover. I then remove the 4 screws holding down the 2 rows on LED lights underneath the drone. With the 4 screws off, I removed the dust plate also.

With the cover off, your can pull the LED power plugs from the mother board sockets. Always do just -1- wire at a time. You won't mix any up. I use a small pair of hemostats like these:

Hemostat On Amazon.com

I didn't buy from Amazon, though. I got a set of 3 - small, medium and large at a flea market. I remember they were about $10.00 for the set.

Follow the wires from the LEDs to see where it plugs into the motherboard (MOBO). I left the front LED and all the motor LEDs in place. The front, white LED is the most helpful. The other LEDs, not so much.

2) WIRING

I removed each set of motor/LED wires 1 by 1 and wound them around the motor support arm. This put the wires further away from the receivers antenna.

I rerouted the main battery power lead until it was just a little longer than necessary to connect to the battery. See picture. I used a small twist ties then cut it short leaving a stub of about 2-3 turns.

I put superglue on the turns to keep it from untwisting. I rerouted the Mobo power leads such that the battery, once slipped into place, would pull directly against the battery connector with just a little slack. 

I have crashed the drone more than a few time. Twice the battery has popped out. Nothing damaged.

The connectors on the batteries are JST style. There are NOT meant to be used repeatedly. So, I sanded the battery plugs with a diamond nail file. You could use sandpaper or another file.

The diamond file takes off only a little material so multiple strokes are necessary. I trimmed the locking portion of the plug until it was NO longer a tight fit.

JST connectors  are meant to hold tight - really tight. Not good if you are going to insert and remove every 5-9 minutes :(  File the plug slightly, check the fit.

File again as necessary until there is still some resistance to the two connector coming together, but no so much that the plug hardly makes a connection.

UDI-U818A MODIFICATIONS Part 2

3) UPGRADING BATTERIES
The original battery as supplied is a 500 mAh 3.7V Lipo. I upgraded to 600 mAh 3.7V Lipos. I bought them off of Amazon. 5X batteries plus  1X  5-way charger cable for about $20.00. 

5 - Way Charger Cable 

The new batteries fit in the same space as the old 500 mAh batteries. However, they are 600 mAh batteries. About 10-20% longer flight time. 

I bought them because flying for 5 minutes and then going home to charge the battery for an hour was not my idea of fun. I carry 20+ batteries. The new batteries are the correct size, but some of the 500 mAh ones that I had fit loose. 

I solved that by adding several turn of electricians black plastic tape of both ends. Snug fit now. This keeps the thinner batteries from rattling. The jacks on the ends of all the batteries are indexed to fit one way only. 

The index mark is a slot and ridge arrangement. I had a time figuring it out. So I painted a silver dot on each connectors side. Now I just line up the dots and pop the connectors together quickly.

The wires going into the connectors themselves are somewhat fragile. So I put a small tab of GEL superglue the two wires just as the enter the red plastic jack or socket to reinforce where the wires enter the jack.

Use Gel, only! Regular superglue is too thin and will wick its way in the metal part of the jack or plug. The I slipped a 5/8" long piece of heat shrink tubing ( 3/16" dia. ) on the battery plug and a slightly larger piece over the motherboard jack to reinforce plugs wires. 

I use a 5" hemostat to stretch all the tubing slightly, for an easy fit bu putting the nose of the hemostat into the tubing and pulling the handles apart. I inserted the battery plug into a jack and aligned everything and heat shrunk it all.

After heat shrinking with a cigarette lighter, I painted on the silver alignment dots. I used Testor's silver paint as it was handy and contrast well against the red of the connectors.

4) TRANSMITTER MOD

I added a 2.4 GHZ removable antenna. Bought it here:

2.4 GHZ Antenna on Amazon.com

I got the necessary SMA female RF coax connector also from Amazon.com. I bought 5x connectors for $2.48 plus - free S&H! Here's link:

SMA Connectors

The UDI transmitter uses a small piece of stranded wire (unshielded) as an stub antenna soldered directly to the transmitter board. It's exactly 31.25 mm ( a little over and inch) in length and is used as a "quarter-wave" antenna.

Antennas for 2.4GHZ  are cut to exact length to resonate at that frequency for maximum reception. If you add wire to the antenna or cut the antenna you could decrease the correct maximum distance of the receiver.

I found it necessary to use a piece of mini coax to connect the router's antenna plug to the connector. Then I soldered the center lead of the coax to the place were the original wire stub antenna was connected. 

One thing left to do. The coax has a shield. The shield is a braided wire wrapped on a teflon insulator surrounding the center lead which carries the signal to the antenna.

The antenna is about 5" long but only the tip is active. Again, 31.25 mm in length. I needed a ground for the coax, otherwise the antenna length would effectively be about 7 inches long. And reception/transmission would be terrible.

I soldered a small 8" piece ( the blue wire ) of stranded wire to the bottom of the coax's shielding being careful NOT to allow the shield to touch anything. 

I also soldered another wire (the black wire ) from the SMA jack. Then I soldered both ends of the blue and black wires to a ground point on the motherboard. See picture in Part 3. 

UDI-U818A MODIFICATIONS Part 3

 

Now the coax is grounded and the shielding of the coax acts like a "pipe carrying water" and on the 31.25 mm tip is the only part that is "active". I tested it - works fine. This is delicate work and requires some skill at locating the ground, etc. If you need a more detailed description of what's done, go here:

 2.4 GHZ Antenna Mod

I removed the old antenna cover and slightly enlarged the hole so the new antenna would fit. I superglued (GEL) the jack to the front half of the transmitters case. Then screwed on the other half and let it set up overnight.

5) RE-WRAPPING WIRING

I wrapped the motor and led wires around the closest motor support rod. This put the wires away from the receivers antenna. I did a test: stock - no wrap and wrapped.

The drone files approximately 1 minute longer with wrapped wires. Not sure why - I only wrapped to make it neater and protect the loose wires.

6) CHANGING ROTORS
Tools needed: #0 Phillips screwdriver. About $2.00 - $3.00 or so. I got mine free when I bough the UDI U818A. Remove screw holding rotor to shaft. See picture.

Be careful NOT to loose the screw. It's really small. Holding the motor casing, pull the old, bent rotor off. Match it to the replacement rotor.

UDI rotors are black or white. Left and right  hand turning (CW and CCW). Make sure the old and new rotor match. Install the new one aligning the motor's D-shaped shaft with the rotors D-shaped opening.

Push down as far as it will go. Re-insert the screw. Do NOT over tighten. Put the drone on ground.

VERY slowly increase throttle until drone lifts off the ground. If it does, you changed the rotor properly. If it flips over, you installed the wrong rotor. Try again.

Is ok? Toss old rotor in the trash and order some more. Your need them. So it was only bent a little? Why change it? It's near impossible to reshape it the same way as it was made. The rotor will vibrate or loose lift. Best bet - replace it and toss the old one.

7) When I did the antenna mod, I removed the flip button, Why? The MODE button is below the FLIP button. I don't do flips. I have enough trouble flying the thing :)

And I don't take my eyes off the drone while flying so I can't look for the MODE button. Hence, the button is a hazard for me. Easy to remove and keep. Problem solved.

KEEP ON FLYING!

ADVICE TO LUKE - AN ASPIRING DRONE PILOT

Best time to fly Luke is early morning just at or slightly before sunrise. It's usually the calmest time of day and no "looky-loos". In my area, the wind picks up slightly about 1/2 hour after sunrise.

Read the manual - again. For Chinglish U818A translations the universal translator doesn't work well. Go here:

U818 TRANSLATIONS

The 100 meters (suggested) flight range in the manual has been changed recently. 30 meters is recommended maximum distance. Seems to be about right. Most likely the drone will be controllable further, but one should never fly to the limit.

UDI U818A when in the air will drop to the ground when out of range of transmitter. That changes when it's on the ground. More like 30 feet. It's the water in the grass, Luke. Sucks up a lot of the xmtr's 2.4 GHZ signal.

1st maneuver to practice is take/landings. Load a battery into the drone. Some LEDs will flash. Ignore 'em. Turn on the transmitter (xmtr). The xmtr will beep once. Set the drone on the ground facing the prevailing wind (if any). The forward part of the drone has the "Horns" or "Eyebrows". They are your "front reference".

Fly with you looking at back of the drone and front of drone facing away from you. All controls are now "normal". If the wind rotates drone, you can use left stick to YAW the drone so it faces away from you. Left stick pushed left YAWS counter-clockwise.

Stand 10 feet or so behind the drone with the drone facing forward as seen by you and "into the wind". Set your iPhone timer for 6 minutes, but don't start timer yet. Remember Luke: your Hoo-man brain cannot keep track of time while concentrating of flying.

BIND XMTR TO RCVR

Push throttle (left stick) rapidly FWD and the immediately pull back all the way. The drone will beep 3 times. This means the drone rcvr has "bound" itself to the xmtr. It's ready to go. Start the iPhone timer. Put it in your pocket. Yer ready to fly...

Push throttle full on and after drone gains at least 10 altitude, back off to about 30-50%. Don't look at xmtr, Luke. Look at the drone. You can't tell when throttle % is correct anyway.

Set the throttle so the Drone will hover or climb slowly. Pull back on right stick, lower throttle slightly and land. Do about 2 dozen or so take/landings. Repetition is how you learn, Luke.

ABOUT HOVERING

Move on to hovering. Make a takeoff and move the right stick as necessary to keep drone in one location. Use throttle to set the height. Try for about 10 feet up. The 818 has a button on the right side of the LCD area. It's called: "high-low speed mold." I think the Chinese tech writer meant: mode :)

Press this once to toggle from BEGINNER to ADVANCED mode and again to go back. All  it does is to limit the movement of the flight controls. Newbies tend to over control (too much stick movement) and can benefit from the beginner mode. Got wind? Use advanced mode:)

DO THE HOVER
Throttle full for takeoff, then when at about 10-15 feet up or so, reduce to about half throttle. Never look at Xmtr. Do it by feel, Luke - use the force.

You'll be looking at the drone for reference. It will get smaller is size as it goes away from you. Sometimes it's not easy to tell which way it's headed. Keep in within 25-40 feet or otherwise close to you.

Use the force, Luke. Remember: Your eyes see the drone, your brain figures what's going on, it sends signals to your hands, your hands control the xmtr, the xmtr controls the drones, and so on...

If the wind picks up, press mode button once and use the ADVANCED mode. This mode is about 2x more sensitive and will allow about 2x more flight control ability (all directions). It's also more sensitive. Neither mode is better than the other. Use what works best - experiment.

When you can hover and take off and land reasonably well, try for short flight distances out, then pull the stick back and go for a landing. Try hover, then fly backwards, then landing. Chop power at about 1-2 feet up.

After a couple a dozens of these, you'll be much more prepared if you "get into trouble." Repetition is how you learn.

Use "throttle off" as primary safety "failsafe". It's your "Help I'm out of control - I'll crash it rather that loose it" solution. Your are flying on grass, right?

Grass or sand will do none or minimal damages to props. Props go first. Remember: when around the Imperial quad geeks, props are not props but are called rotors :)

SOME RULES:

1) Nobody flies your drone except you. Not even chewbacca! Not being a "hard a**" here. These things can be "a liability" if it crashes into a person, place or thing. And you know Chewie... all thumbs :)

2) When the iPhone alarm sounds, land the quad immediately, change the battery - and fly some more. If you leave the transmitter on, you will NOT have to re-bind. Pay attention if you leave the xmtr on. If you move the throttle fwd, the rotors will spin.

Oh, were your fingers in there, Luke? Ouch! Go home when you are out of batteries. Log the flight time and location in log book. No log book? Use a piece of paper and a pencil.

Then go buy a log book: 

PILOTS LOG BOOK

3) Imperial Law says, NO drone flying within 5 miles of any and all airports. Say under 400 feet AGL (above ground level). No problem officer, it won't fly that high :)

4) Fly safe. No "hot-dogging" for the first 10 hours.

5) Be calm when people want to talk to you while you fly. Land the quad. Chat.  If kids (under 15 Y.O.) are around, they will gather like a flock of fynocks and gawk at you. You will NOT fly with them around, Luke. If your not sure if to fly or not - DON'T FLY!

6) Safety is ALWAYS job #1. Although it's rule #6 here :)

7) Don't plan on it "being fun". It will be more like, well - work. With some apprehension and a tad bit of fear tossed in. Goes away after a while. Goal is to learn to fly. Have fun later.

8) Don't worry about crashing. You will. Guaranteed. And it will happen often. Try to figure out what you did that caused the crash and learn from it. Know that sometimes the drone will just "drop out of the sky" and for NO apparent reason. It happens. Expect it.

9) The time you spend when arrive at the location to fly until the time you leave said location is the total flight time you will log. Use 5 batteries? Fly for 6 minutes each? 5 x 6 is 30 minutes. That's NOT your total flight time.

Reason: battery changes, xmtr binding, setting/resetting iPhone timer, walking to pick up drone that got out of range and went down, and other stuff. Don't bother writing it all down.  You log from "time in" to "time out". That's how ALL pilots do it. Start to stop.

10 ) Stop if it gets windy. How do you know? In advance mode the controls are ineffective. The wind seems to be pushing the drone around the sky, because - it is!  Land - go home, Luke.

Repeat the first lesson for several flights. You can add other maneuvers as you feel more comfortable. Flying in light wind can be challenging. Go for it. Make up your own exercises - fly left to right and repeat, foreword to backward and repeat, etc.

Everything you do is training and you will learn. The more you fly, the better you'll get.  It's just a matter of time. Repetition is how you learn. And don't forget to use the force, Luke.

Yoda

PS Thank you I do for the droid parts. Get them here on Tatooine, I cannot!

WHY I BOUGHT THE UDI U818A QUADCOPTER

I used the entries topics below to compare the feature of the UDI U818A drone to other quads in the $40 to $80.00 range. You can do the same. 

The UDI U818A is the most popular selling drone on Amazon.com. It's the 82nd most popular toy on Amazon.com. It's a very good drone training aircraft. I bought 3.

1) Price. $53.90 at Amazon. Free shipping!

2) Size is approximately 13" square and about 2 1/2" tall. Easier to see it in the sky than smaller drones. "Eyebrows", "horns" or "mustaches" on the front of the quad also helps identify which way it's flying. Made for outdoor flying.

3) Geared rotors. Hover not as twitchy due to larger mass of the rotors and correspondingly slower rotational speed.

4) Reasonable flight time. Flight time given by UDI is: 7-9 minutes. I stop at 6 minutes to keep the battery usage in the "proper range" -  not totally drained at the end of 6 minutes, the batteries typically read 3.68 volts or above. 

That's about 10% remaining battery juice before damaging itself.

       NOTE: U818A Quad kit comes with (1) 500 mAh battery.
     I use 600 mAh batteries. Same physical size, last longer.
     15 of the 600s gives me 80 minutes of so of flight time.

5) Has a fixed iris video camera and can take stills. Quality given as: "VGA". Translation: grainy video and photos. Good for training, though. This is NOT FPV (first person view) video.

6) Parts are cheap and readily available. Be sure to keep at least 2X spare sets of rotors. There are 4 different rotors. 2 front and 2 back of different color and rotation: CCW and CW. That's 8 spares total for 2X sets. 

A full set (4) cost $2.28 on Amazon. Be sure to buy at same time as quad to get free shipping.

Spare rotors at Amazon.com

After a crash, sometimes the rotor(s) well get bent. You can bend it back, but it will never be the same. Recommend you change it after the days flying.

7) Transmitter. Low output power limits the range. I try to fly the quad within 10-120 feet of so. Transmitter batteries last forever (4X AA). Batteries not included.

8) Mode 1 and 2 switch. Mode 1 is "Beginner" mode, Mode 2 is "Advanced". Mode has to do with how the quad reacts to input and the maximum allowable angle the quad can achieve. 

I will switch modes depending on the wind, and the type of maneuver I want to accomplish. Hovering in "no wind" is very easy in beginner mode.

Mode 1 allows only low pitch angles making for a lower forward speed and a slightly slower response that helps from pilot over controlling.

You can switch live between the two while flying at any time. Be sure not to press the button above the Mode switch. That's the "Overturn" (flip) aka the "Eversion" function. If the wind picks up while in the air, flip the switch to Advanced mode to get more control.

9) LCD shows: percentage of motor RPM, trim settings, camera on/off, photo take, battery voltage as a bar graph, antenna reception. A picture of an antenna shows when power is on.

10)  Power (on-off) LED (Green)

11)  On - Off switch is easy to find.

12)  Right button on top of case turns quads LED lights on and off.  

13)  Two font rotors are white, rear are black. Helps a little. At 50 feet, they look the same, though.

14)  Instructions are ok. Be sure to read "UA5 Transmitter (4 axis) Calibration Instructions". Some amount of "Chinglish". See the translation guide posted on this site:

Chinglish Translation - U818

15) A matching pre-cut to fit, foam lined, aluminum flight case is $29.95 more. Holds batteries, chargers, quad, etc. Very nice. 

 Flight Carrying Case on Amazon

16)  Comes delivered in a cardboard shipping container that can double as a flight case. Instructions are pretty good.

Quadcopter Box includes: 

1 x U818A RC Quadcopter with Camera
1 x 2.4G Remote Controller (does not include 1.5v AA batteries)
1 x AC Adaptor for charging battery (not voltage accurate)
1 x 2GB MicroSD card
1 x USB to MicroUSB cable for downloading video out of camera
1 x bag - 4 each, rotor pinions gears
1 x Small Phillips head screwdriver
1 x set of (4) rotors - 2 white, 2 black
1 x LiPO 3.7V 500mAh Battery

Keep the shipping/presentation box for a flight case.

Where to buy:

Buy on Amazon.com

Keep on Flying! 

BATTERY CHARGING USING THE B6 - Part 3

START CHARGER

Be sure you follow, exactly, the printed instructions included with the charger. B6 charger charge parameters I use are:  LIPO - 3.7 V - 1.2 A. Press and hold the "Start" button for 3 seconds to begin charging. 

The charger will check your settings (LIPO - 3.7 V - 1.2 A),  and read the voltage of the battery to be charged. The "battery" 5x pile on the cable will be "seen" by the charger as: 1 battery at 3.7 V (nominal).

Remember they are in parallel ( all + to +, and all - to -,  and done automatically by the cable wiring). This means the voltages don't add, just the mAh values. 

Effectively those 5X batteries are now seen by the charger as one (1) battery @ 3.7 V, but the charger doesn't know there are 5X are in parallel.

What it will do is charge them all at the same time until it reaches 4.2 volts. This will take longer as  compared to a single, 600 mAh battery. 

But since the charger is set to 1.2 A ( double the UDI charger rate), the actual time will be closer to 2.5 hours for 5X batteries. That's about twice a quick as a single battery charging at 600 mAh. The B6 charge current will be about 240 mils per battery.

If all is correct it will allow you to press "Start" again and begin the charge sequence. In will automatically shut off at 4.2v (standard 100% or full charge). You are doing a parallel charge of 5x batteries, the shutoff will occur automatically at 4.2 V.

Check the voltage of all the batteries after the charging. There may be 1 or 2 batteries charges to 4.18 or so. Close enough. After measuring and sorting out the fully charged 4.2 V batteries, charge singly (one at a time), the remaining, now slightly undercharged (below 4.1 V) batteries. 

When the charger is done, it will shut off automatically. Put them in finished pile. When all are done, put the finished batteries into your flight case or box or what ever else you use to transport you equipment in.

Any batteries left? Repeat until done. I use 3X B6 chargers. I do 5x batteries per charger. It takes 2+ hours to complete the charge cycle at 1.2 Amps. With 3X chargers I can do all 14 batteries in about 3 hours. 

That's a lot better than the UDI charger which would have taken 15 hours to do 15 batteries. Then I'm ready to fly again. Why 14 and not 15 batteries? I fried one battery using the charger that came with the UDI U818A :(

BAD CHARGER!

First couple of times the UDI charger worked correctly, Them, for no apparent reason, it charge the next battery to 4.5 volts before it shut off. 

Yes, the battery died. 

I also have other chargers. Cheap stuff  I got from eBay. About 1.5" square, 5 charge ports, and uses the USB port on my computer for power. Works ok. It too has overcharged batteries. Now I use the B6 for ALL final charging.

KEEP ON FLYING

BATTERY CHARGING USING THE B6 - Part 2

You can buy a voltmeter at Amazon,  Home Depot, or Lowes, Harbor Freight, etc. $10 to $20 and up. Doesn't have to be a "Fluke" brand meter (very expensive), any meter will do and save you from overcharging your LIPO's. 

As you test the batteries, sort them into groups of "like voltages" using increments of .1 ( 1/10th ) of a volt as follows:

PILE #1   3.7 to 3.79 volts

PILE #2   3.8 volts and above

PILE #3   below 3.7 volts. 

3.7 is the "nominal voltage" of a 3.7 V LIPO battery. It's effectively "dead" (for flying purposes) at 3.7 V, but does leave about 15% of a useful battery charge left. You DO NOT want to take the battery voltage below 3.2 V. 

3.2 V is the critical "I'm about to really, really, really - go dead - and forever!", voltage. Fortunately, the quad's computer will "cutoff" at somewhere around or typically slightly below 3.7V. The charging voltage is about 4.5 volts and the correct 100% fully charged voltage (and charger auto cutoff) is 4.2 Volts.

WHERE TO GET THE 5 WAYS

You can get 5X 600 mAh batteries with a 5 way cable for a UDI U818A for about $24.00 from Amazon.com.

     UDI Batteries and 5 way Cable

Make sure if you buy batteries and cable as a package that the batteries actually fit your quad. I like to buy the batteries with the 5 way cable, included. It's cheaper buying in bulk too and I take a LOT of batteries when I go to fly. 

Buying the cable alone is about $2.00 with free shipping from China. About 3-4 weeks delivery. But, hey! Free shipping! Same cable sold in the USA, $5-7.00, each. 

I recently bought 3 each from China:

     5 Way Cables From China

$5.87 for 3 pieces. Free shipping! Can't have enough 5 way cables.

EQUALIZE

I take 5x "dead" batteries out of the pre-sort pile and put them on a 5 way cable. Do the same for the remaining batteries. I leave them on the 5 way cable for about 20 minutes or so. 

Note: they are NOT hooked up to charger. The weaker ones are charged up slightly by the stronger ones. The pack tends to equalize itself - but not perfectly. And that's ok.

You have finished the equalization and you have 1 to x number of piles of 5 each batteries on a separate 5 way cable and they are about the same voltage. 

If you have a lot of batteries and only one B6, charge each pile of 5 separately on a 5 way cable to 3.9 to 4.0 volts using the any LIPO charger. If your are JUST using the B6, skip to the "START CHARGER, otherwise you'll need to check the batteries occasionally to see what the actual voltage. 

If not using the B6, stop at less than 4.0 volts to be safe.

KEEP ON FLYING

BATTERY CHARGING USING THE B6 - Part 1

Here are the instructions for using the B6 computerized, battery charger to charge 5X LIPO batteries in parallel. I charge my UDI 500 or 600 mAh batteries using this method. The B6 is a Chinese made battery charger that can charge LIPO, LION, LiFe, NiMH and lead acid (Pb) batteries. 

It can handle multiple cell batteries and has a balancing function. It will charge all small drone batteries up to and include DJI Phantom quadcopters 11.1 V @ 5200 mAh battery. It comes with everything you need except:

1) The 5 way cables

2) The power supply

TECHNICAL STUFF

I use a 500 mAh 16 VDC out, wall wart as a power supply 'cause that's what I have as the power supply. You can use any DC output wall wart that outputs between 11 and 18 volts. Even a car battery!

Note that some B6s use a 2.1x5.5mm power input plug and others use a 2.5x5.5mm plug. I have 3 chargers. 2 are 2.1x5.5mm, and 1 is 2.5x5.5mm! It appears from all the literature I have read that the 2.5mm is the current charger jack size being shipped.

There is nothing included in the printed manual giving the size of the power source's required plug size. I suggest getting a charger with a 2.5x5.5mm plug. That's what vendors are selling on eBay now:

B6 Charger with 2.5x5.5mm plug on eBay

To charge 5x 600 mAh LIPOs, at 1.2 Amps,  you need a charger with at least 500 mA output. If you use a charger with less than that (as I initially did), the voltage output of the charger will drop to below 11 volts DC and the B6 will not charge.

I experimented and found that I can use a 500 mAh "wall wart" charger and charge at 1.2 Amps maximum for 5X 600 mAh batteries. The 5 batteries are "spread over" the 1.2 amps for about 240 milliamps each.

COMPUTE THE REQUIREMENTS

The total input "wall wart" wattage required is not shown in the B6 manual, but the input charging wattage can be calculated. The 4.5 V (approximate charger charging voltage) multiplied by the target charging current of 1.2 Amps is 5.4 watts. 

You'll need something higher ( maybe 20-30% higher - depends in the chargers efficiency ) to charge at the 5.4 watts required. 30-50% is safe - lower stress on the charger and wall wart. This means the charger will have to output at LEAST 200% of the required 5.4 watts. That's about 11 watts.

11 watts divided by low lowest allowable input voltage of 11 volts is 1 ampere. Therefore, as calculated here, you will need a 11-18 volts, with a 1 Amp output charger to do the job. There will be some "cushion" as the charger will put of slightly more voltage. 

The result is the charger will last longer as it will not run hot. If the charger gets too hot, it means the charger is outputting too much current and may damage itself. Can't have that!

SO GET A WALL WART, A B6, 5X CABLE AND LETS GET STARTED

After flying, individually test the voltage of all the batteries using a voltmeter set to DC and with a maximum voltage selected that it higher that batteries highest voltage which is 4.2V.

I use the 20 volts DC scale. The next DC scale down is 2 volts - too low. You can use a higher meter setting but NOT a lower setting. If you get a "weird reading" check to see if your on "DC settings". DON'T use AC settings. Reads wrong :(

KEEP ON FLYING

PILOTS FLIGHT LOG

Also know as: Flight Log, Log Book , Drone Pilot Log, etc. It's used to keep a permanent written record of your flight time. There are multiple entries. I use this one for drone flying: 

 

  PILOTS FLIGHT LOG

 

The entries are: 

Date, Flight #, Drone info (model), Flight location (where you flew), Flight Conditions (weather, etc), Operational Issues (problems & situations), Remarks & Comments (anything else), Piloting Time ( time in, time out, total time).

 

The entries run from left to right. The in/out times are added to produce the total time. The total time is added in column format to get the page total. The page total is added to the previous page's total.

 

Do you need a Flight Log? Well, yes and no. 

 

The FAA (Federal Aviation Administration) says,  if you are a pilot (PIC - Pilot in Command) flying any airplane at any time (even as a student), you WILL keep a flight log. 

 

But, they also disregard any "RC modelers" who fly model aircraft and/or drones, because they are NOT actually seated in the cockpit :)

 

If you are NOT going to charge money for your flying, you do NOT legally need flight log. If you DO plan on eventually charging money, the FAA will REQUIRE you to produce your log book(s) on demand.

 

Should you start using a log book now? Yes, I think you should. I predict that in the very near future, the FAA WILL require log books for drone pilots. 

 

It's a way to control and keep track of people. And control for drones is a big concern - no pun intended :). 

 

Expect it - it will happen.

 

In any event, it's a good idea. I can look back and tell you how many different drones I've flown and when the motor of my first drone died. I can tell you if most of my flying was during windy conditions - it was. I can show my total hours flight time. It's all there.

 

What about verification? Who's to say I just didn't make it all up?  I could have. If I ask the FAA for a waiver to fly comercially, they might say, "You'll need a flight check". 

 

I'd be screwed if I actually hadn't flown the hours I said I did. Don't mess with the FAA. Keep accurate logs.

 

The FAA rules are currently in a state of flux. They change almost daily. I believe log books for ALL drone pilots could happen. In fact, I'm betting on it. So should you.

 

One more thing. Remember that any entry can be read by anybody at any time. If you log "that flight", you know, the one where you took your Phantom 2 up to 800' AGL (Above The Ground) ?  

 

"Oh, yeah. That was killer!" 

 

Well, you just documented a crime in the eyes of the FAA. Maximum flight height for a drone is 400 feet AGL, or 200 feet AGL commercial usage or slightly higher with a waiver.

 

Don't log the evidence :) 

 

KEEP ON FLYING!