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Multiplex MiniMag

MiniMag
Cute box

MiniMag
Everything in the box

MiniMag
Glued the spars in the spar joiner

MiniMag
Spars glued in the wing

MiniMag
Extended servo wires with a MPX plug

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Servo placed in the wing

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Control-horn and linkage in place

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Canopy latches glued in place

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Canopy latches glued in the canopy

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Servo in place in the fuselage, trimmed away some foam for the control-snakes

MiniMag
Linkage in place

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Since I’m going to use a steerable tail wheel, I trimmed away the foam tailskid as recommended in the manual

MiniMag
Tailwheel driver wire bent and done

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Made it fit in the foam

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Wing bolt support glued in place

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Fuselage halves glued together

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Glued the undercarriage support

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I had to dremel away some plastic to get the brushless outrunner to run without rubbing

MiniMag
Another view of the motor

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Motor glued in place

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I made a “fast connector” for the servos. I got the idea from the Multiplex Blizzard

MiniMag
Servo connector on the wing

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I really like not having to hook and unhook two small connectors all the time. Now I simply put on the wing and screw it down and it’s done.

MiniMag
Landing gear in place

MiniMag
Always use Loctite on metal to metal screws

MiniMag
Tail wheel in place

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Time to do the floats

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Bending some metal

MiniMag
Water rudder is made from 1,3mm steel rod and depron

MiniMag
Rear mounting plate for the floats

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Front plastic glued

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Back plastic glued

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Holders in place

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Test fitted. It takes about 5 minutes to switch between wheels and floats

MiniMag
I made a little compartment in which I placed a low voltage LiPo alarm since the flight time will be varying so much

MiniMag
ESC and battery in place

MiniMag
Ready for a maiden flight

MiniMag
Up, up and away!

david
Time to fly

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The MiniMag flies even better than I expected. It has an extremely low stall speed and it’s very gentle flier.

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It looks good in the air as well.

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Looks awesome with floats as well.

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A great plane not only for the beginner.

Motor: KDA20-20L 1053kV
ESC: 20A Hobbyking SS
Battery: 3s 1800mAh 20C LiPo
Servos: 4 x HXT900
Prop: 9*4,7 APC
Power: 13A @ 11.7V @ 9350RPM = 152W @ 67km/h
All up weight: 601 grams (with wheels and battery)

Maiden flight video:

Disassembling the Camileo P10 HD camera

I have done a step by step disassembling guide of the Toshiba Camileo P10 HD camera that I intent to use for FPV flying. My goal was to shed some weight and get a good look at the connector between the main PCB and the sensor PCB. The final goal being world domination… No I mean a being able to pan/tilt only the sensor by adding a ribbon cable of some sort.

How much weight do you think I saved?

Here is a direct link to the guide

The complete guide to getting started in FPV!

At last, it is done… The guide to getting started in FPV! This was by far the hardest guide for me to write. How deep should I go, what is relevant? After many, many hours of hard work and tears I finally have a guide that I think will be appreciated by many.

This guide gives a in depths knowledge of the basic FPV components as well as gives a taste of the more advanced gear. Read it and write what you think!

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FPV Starting guide

In this guide I will try and help those of you that want to get started with FPV (First Person View) but don’t know where to start or what to buy. I will try to teach you what to look for and what to look out for when choosing your first components. The guide is segmented into two parts “The basic FPV setup” and the “The “advanced” stuff”. The first part being more in depths, giving basic understanding, and the second part is more of a “carrot” showing ways to enhancing the FPV experience once you got going.

Introduction
FPV flying isn’t quite as easy to do as one might think – “It is like learning to fly radio control all over again”. Do not attempt to fly full FPV the first few flights! It’s best to either fly your plane normally (visually) with the FPV gear on it and record the flight so that you afterwards can watch the recording and get used to the FPV point of view, or have a friend fly your plane while you watch the video feed. The important thing is to get used to navigate from the air, which is quite a lot harder than it sounds. A good tip is to before the flight, spot out big landmarks that are easy to see from the air and remember how they are located in relations to your self. You do not want to get disoriented in the air, that will most definitely lead to a crashed or lost airplane. A friend that can visually follow the airplane for you (a “spotter”) and take over if you get disorientated or the video gear malfunctions is a good idea. Take it slow, don’t rush things. It’s easy to loose a FPV airplane.
Other than that you will need these things to succeed:

  • Skill enough to fly/stear a RC vehicle visually
  • Basic electronics understanding
  • Soldering skills
  • Free time
  • Patience
  • Money

If you got that were good to go!

What airplane is suitable for FPV
To be able to do FPV you need a vehicle of some sort. It can be a car, boat, heli, hovercraft or what ever you want. Since most people that want to do FPV fly airplanes, I will be using that as my starting point to this guide. So what is the best beginner FPV airplane? That is a tricky question since it depends on taste. You first FPV airplane should be:

  • Stable
  • Easy to fly
  • Able to carry extra weight
  • Roomy inside the fuselage

There are many different airplanes out there that are good for FPV flying, and different people like different airplanes, If I had to recommend an airplane it would be the Multiplex Easy Star. It fulfills all points on the checklist above with ease, it can also take extremely much abuse and it can be modified a lot and still fly great. For these reasons it’s by far the most used FPV plane out there. The Easy Star is also the perfect first airplane for those of you that can’t fly RC yet.

Here is a link to my Easy Star FPV build log
Here is a link to my review of the Easy Star


 The basic FPV setup


To begin your FPV journey you need at least these 4 items:

  • A video transmitter – To transmit the picture to the ground
  • A video receiver – To receive the picture on the ground
  • A camera – To have a picture to transmit
  • A video display/goggles – To watch the video feed from the airplane

This is the BASIC setup, the absolute necessary stuff to be able to fly FPV. I recommend to start out simple and then expand with the more advanced stuff once you mastered the basics.

The video transmitter
At the moment there are 4 different frequency bands to choose from when it comes to transmitting video, and they are; 900MHz, 1.3GHz, 2.4GHz and 5.8GHz.
Before you choose what frequency you want to use you need to do some research of what frequencies that are allowed in your country, for example; 900MHz is not allowed in Sweden because it’s used by air traffic, and if any license is needed to transmit on any of these frequencies. In most countries you are allowed to transmit up to 10mW of video on the 2.4GHz band without a license. You also need to take into account what frequency your RC transmitter utilizes; if you fly on 2.4GHz, you can’t use that frequency for your video link as well.

Here is a list of the pros and cons of the different frequencies:

900MHz and 1.3GHz
+ Less influenced by obstacles due to lower frequency
+ much less “crowded” frequency
+ Works with 2.4GHz RC transmitters
– can interfere with GPS signal
– hard to find antennas
– not that many transmitters/recievers to choose from

2.4GHz
+ Easy to find a wide variety of antennas
+ Many transmitters/recievers to choose from
+ Doesn’t interfere with GPS as much
– More influenced by obstacles
– More “crowded” frequency
– Don’t work with 2.4GHz RC transmitters

5.8GHz
+ Easy to find a wide variety of antennas
+ Doesn’t interfere with GPS as much
+ Works with 2.4GHz RC transmitters
– Even more influenced by obstacles
– More “crowded” frequency
– not that many transmitters/recievers to choose from


A 1.3GHz 300mW transmitter

Ok, now that you’ve chosen the frequency you need to know how much power to get.
“There is no such thing as to much power” – Or is there?

A transmitter with higher power will:
+ Have longer range
– Be bigger
– Be heavier
– Produce more heat and may require a heat-sink (even more weight)
– Draw more current
– Be less efficient

A common misconception is that doubling the transmitter power will give you double the range. This is not true, doubling the transmitter power will only give you 1.414 times longer range (The square root of 2 or 3dB). The best choise in my oppinion is to use a smaller transmitter and a patch antenna (more about antennas later on) on the receiver to get extra range as you normally won’t fly 360° around yourself.

There is no use in having trice the range on your video link than on your RC link. These are my suggestions if you use a standard RC link:

~300mW 1.3GHz / 900MHz transmitter
or a
~500mW 2.4GHz / 5.8GHz transmitter

Plus a ~9dBi Patch antenna for the receiver

These combos easily gives about 2-4km of crisp video which is more that you need if you fly with a common RC link. They will also be light, use less current and not be prone to overheating. A good balance for your first setup.

The Receiver
This is the easy part. When you buy a transmitter you will almost definitely be able to buy a matching receiver from the same place. As long as the receiver works on the same sub frequencies (ex 910MHz, 915MHz..) as your transmitter your good to go. Sometimes you will have the choice to buy a “dual output” receiver, which means that is has two composite outputs, which is nice if you want to record you flights or have a “passenger” screen/goggles. But you can get a separate composite “splitter” later on if you want to.

The camera
Any camera that has a composite output will work but there are some qualities to look for in a camera when picking one for FPV use. The most important one is fast brightness adjustment, this is because the brightness varies so much and so fast during a normal FPV flight. If you use a camera that’s slow to adjust its brightness you will end up with a useless picture during nearly the entire flight, and you might even crash.
Other qualities to look for is obviously small and lightweight. But now comes the tricky bit… Image quality. Why is this the tricky bit? Because “beauty is in the eye of the beholder”. Different people value different things when it comes to “image quality”.

Some like bright colors, some like a brighter picture, some like higher resolution and so on. This is why I can’t say; “Buy this camera, it’s the best one”. You need to compare different cameras your self to find the one you like the best, and the simplest way to do that is to watch other peoples FPV videos. But before you do that here is a good thing to know:
There are two different types of sensors that is used in cameras; CCD and CMOS. (The sensor is the part that actually captures the light and converts it into a digital image.) These two sensors work in different ways and both have their strengths and weaknesses. Neither is categorically superior to the other. I will try to summarize the pros and cons for the use in FPV of both these types:

CCD:
+ Better in low light situations
+ Low noise
+ More pixels/area
– Suffers from “smear”/“bleed” (Vertical lines when exposed to bright light)

CMOS:
+ Eatch pixel can have brightness/contrast correction
+ Less power consumption (up to a 100 times less!)
– Picture gets distorted with vibration (wobbly image)

Modern CMOS sensors has an advantage over the CCDs and that is that they can adjust the brightness/contrast of every pixel. This means that you can see both the ground and the sky correctly exposed at the same time! This is where the CCD struggles, on a sunny day you either see the ground correctly exposed or the sky but not the both at the same time.The CCD also suffers from “smear”/“bleeding” which means that when pointing the camera at a bright light, lines appear in the picture which can in turn lure the camera to underexpose the picture. Here is a picture of the phenomena. However the CCD has an advantage when it comes to handling vibration. On a CCD the picture simply gets a little blurry with small vibrations, where on the CMOS the picture gets “wobbly”. Here is a video of the phenomena. This can be a problem especially if you want to use a heli for FPV. On an airplane this should not be a problem if you have a properly balanced prop. If you want to read more about CMOS vs CCD this homepage is a good place to start

Most cameras that can be found in FPV shops are relabeled security cameras, f.ex the real name of the KX-171 camera I’ve used is “480 tvl 0.2 lux, 1/3″ SONY® super-HAD® CCD, 12VDC”.

Matching equipment
One thing to consider is to choose a video transmitter and a camera that operates on the same voltage, as this simplifies the powering of the two. If you use a 12V camera and a 12V video transmitter you can simply run both of them directly of a 3s LiPo. If you use a 5V setup you need a voltage regulator which adds extra weight and you will lose some efficiency. I recommend using a separate battery for the FPV equipment, it’s much less trouble than powering them from the main pack as you most certainly will experience severe interference in the video link. (Altho this can be overcome buy adding a couple of filters)

The display/goggles
Now that you’ve chose the video transmitter and camera you need something to display the image you’re transmitting. The cheapest alternative is to get a small TFT display, like 7”, and mount it inside of a box to block out sunlight, a so called “Geek box”. It’s cheap but isn’t very practical (nor good looking). Just be sure the screen has at least 640*480 pixels of resolution. An other alternative is to buy your self a pair of video-goggles.

They are much more practical and in my opinion give a much better experience when FPV flying. When choosing video-goggles I recommend a pair with at least 640*480 pixels resolution. Any lower and the experience will suffer greatly as it will “smudge” out the picture, destroying the details. Another figure to look out for is the FOV (Field Of View) angle number. This number tells you how big you will experience that the picture is. A higher value is better. When this is written the goggles with the best FOV is the Fatshark RCV922 with 46°. Not all manufacturers print this number, but some does gives a size of a “virtual” display experienced at 1 meters distance, usually 58” or something similar. Also in this case the higher value is better. Other than that it’s not much to look out for when choosing goggles. If you get a chance to test the goggles on before you buy them, take it. Try them on and make sure they feel “right”.

You’re done!
You now have what you need to do your first FPV flight. The next segment will cover the more “advanced” stuff that you might want to get further down the road. I will not be as “indepth” about these topics thou, but rather give you a simple taste of what they are. Even if it isn’t needed to fly FPV I strongly recommend getting yourself a recorder to be able to revisit your flights. This will help a great deal when learning to fly from the airplanes perspective. I can also recommend getting a patch antenna from the start, they are a cheap way to increase your range at the cost of 360° reception. But how often do sit in the middle of the field and fly around yourself?


 The “advanced” stuff


Recording
Recording your FPV flights is a good idea, not only to be able to share your flights with others, but for you to be able to revisit and study them. Especially in the beginning, when you are learning to navigate from the air. To be able to record you need a “dual output” video receiver or a “composite video splitter”. Making a simple Y connection is not recommended as it decreases the video quality greatly. You need something to capture your video with, and here is the most popular ways:

  • Camcorder with AV-Input
  • Digital Video Recorders (DVRs)
  • Computer with a video capturing card

All these work well and are not that hard to come by. I’ve been using a Sandisk V-Mate, which is a DVR that records onto a SD-card. It’s not great, but it works. I recommend getting something better. Search the net and find out what’s the best for you. Here is a very good list with recorders that work well for FPV use.

Patch antenna
This is an easy, fast and cheap way to get extra range if you plan to fly in front and not 360° around of yourself. A 9dBi patch antenna will give you roughly 2-3 times the range of the stock whip antenna, but it will still have a quite large beam width. I have flown with a

patch

patch antenna on the receiver since I started with FPV and I have never felt limited by it, but to each his own. I can recommend reading my guide “A simple explanation of antenna gain” which will give you a greater understanding of antennas.

Pan/Tilt
To further enhance the FPV experience I can recommend building or buying a pan/tilt system. It’s just two servos that either pans (making the camera look right/left) or tilts (camera looking down/up) the camera. You don’t need to get both at once. You can start out with just the panning as this is the most rewarding axis.

You can control the pan servo with channel 4 if you’re using a 3 channel airplane like the Easy Star, and simply control the panning with the rudder stick. Or you could hack the cannel 5 and 6 switches with pots. Or you can buy a headtracker. There are many solutions.

Headtracker
Is a device that converts your head movements into servo movement. There are a few different brands of headtrackers on the market today that you smack on your head and simply plugs into the trainer port of your transmitter. By using accelerometers or magnetic field sensors they detect the head motion and send a PPM signal to the transmitter. But you can also build your own;

My DIY headtracker, the Hat-Tracker.

OSD
Short for On Screen Display. What it does is that it superimposes text/graphics onto the picture giving you real time information from the airplane.

I can recommend getting a OSD as one of the first “upgrades” for your basic FPV setup. They are quite costly but they are well worth it. If you can afford it, get a OSD with GPS. Then you will be able to know your speed, altitude, distance to home, a directional arrow to point you home and some OSDs even have a “return to home” function that flies your plane to where you started from if it looses the RC link.

Diversity
Video diversity controller – Is a unit that you plug two video receivers into and the unit automatically selects the receiver that has the best video signal and forwards it to the output. This means that you can:

  • Minimize the “dead” area that you get from just one receiver
  • Use 2 patch antennas to get a much wider beam width
  • Use 1 patch antenna and 1 omni for long range and 360° close range
  • Two different video frequencies can be used on one airplane

If you plan to fly at high speed near the ground close to your self this is a great way to get a smooth picture. At the moment diversity controllers are quite expensive but hopefully more manufacturers will start making them and the price will drop.

Antenna tracking
With some OSDs you can buy an antenna tracking pod that uses two servos continually point a high gain directional antenna (ex a patch) at the airplane. The antenna tracker uses the GPS data from the OSD and uses that to keep the antenna pointing at the airplane as it flies around. With this setup you can use a much higher gain antenna than you normally could use as it’s able to keep the plane within the narrow beam-width. These are very pricy at the moment and hard to come by.

Long range systems
Are available on the 433MHz an 869MHz bands and offer a RC range of up to 50km+. These systems work as “transmitter modules” which mean that they plug into your transmitter and simply transmits on a different frequency that your transmitter normally do. These systems are very expensive but effective. For those of you that want extreme range and have deep pockets.


Did you enjoy this guide? Anything you feel is missing? Leave a comment!

 

Finally a new HD camera

Nearly 2 months ago I got myself a Aiptek AHD300 camera that I had planned to modify for FPV flying. But it turned out that the webshop I bought it from had printed that it could do 720p in 60FPS, but it turned out it couldn’t.
So I sent it back, to buy a cheaper cam with almost the same specs. But why have it taken such a long time to get the new camera?
Continue reading and more pictures click the “Read More”
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