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Posted by PeterVRC | May 19, 2015 @ 07:13 PM | 846 Views
I have had this jet a LONG time now! It was my first 70mm EDF jet!
I actually have two of them....

Mine are Version 1's, but be sure to get the Version 2 if you buy one! They now come WITH retracts. I had to modify mine to have retracts - though I guess I got to do what I wanted and make it truly robust.

Hmmm, it looks like a HABU !! I guess it is a clone of that excellent flying jet, and thus why this one is excellent too!
It is totally fine to fly it as it comes in its 4S guise.
Or upgrade the ESC (only) to 90Amps so you can run the stock plane on 5S - which stresses the motor but MOST people have had theirs cope with that. Some go up in smoke....
Or change the whole fan combo to a higher Power setup. 1000W.... 1200W... 1300W... 4S, 5S, 6S.... CS10, 12, 14... Wemo EVO, Pro...

It is a very sleek jet, which means it can fly fast! Like a missile - though not so fast on the stock 4S setup. Still fast though!

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Posted by PeterVRC | May 07, 2015 @ 06:25 PM | 961 Views
After having bought all kinds of CHEAPER bits for EDFs and building up a bit of everything you can do that way, I decided to get an ExtremeRC ready to run combo.
I could still have done that the same myself, but it is not much more to have it all done and ready to use so I figured I would do that to check it out.....

The ERC Jetfan combo choices are here:
http://www.extremerc.com.au/estore/i...ath=146_11_375

I wanted something above 'average' in power, so I chose the 8S 3000W combo - you can always use lower Throttle! hehe

I actually already have two Jetfan Rotors and Wemo EVO Rotors, but have not assembled those because getting a suitable CHEAP motor is not easy/possible.
The HK Fandrive 3968-1500kv CHEAP BEAST ($74) is a really great motor... but it has an 8mm shaft which Jetfans and EVO's cannot fit! BAH.
A suitable HET motor costs $160

The ERC specs for this combo are:
29.58v / 101A / 2990w / 4.5+kg thrust (1.52 Thrust to Power)
And there is a video to show/prove that!!
Those are good numbers!! This shows the motor is coping with that load just fine.

When I set mine up and tested it I got:
28.1V 93.6A 2620W 4.00Kg - using 2x 4S 4400mAH 65C Turnigy Nanotech (also 1.52 Thrust to Power)
But you can see the VOLTS dropped a lot - the battery cannot do that load comfortably!
These numbers also show that the ERC numbers ARE in line with what you would get if you had a better battery.

Once in a jet, with reasonably decent ducting, you should get 1.3x to 1.4x the WATTS in Thrust. So mine at 2600W = 3.38Kg to 3.64Kg. Which should be the upper region of a jet's AUW for that anyway. WAY more Thrust than you truly need in most cases! But you do 'need' a lot if you want your scale jet to also be able to do a scale TOP speed!

Note this test below is using Revo batteries, but the HK Nanotechs (plain Nano) can drive the combo to another 200g higher Thrust. For almost 4 Amps more input.
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Jetfan-HET, HET650-1600kv 8S 4400mAH 60C Revo 90.6A 27.4V 2470W 3.87Kg (1 min 5 sec)

Posted by PeterVRC | Apr 14, 2015 @ 11:38 PM | 5,790 Views
Quite a while back I had bought a second FW Su-35 KIT with an aim to make it up for an 8S and 3000W+ setup. After badly damaging the first one I decided to get this underway and done ASAP. (this was a few months back now!)

The aim is to fly from GRASS.... have approx 4.0Kg AUW.... an 8S setup that can do 4000W on the bench, with 5.2kg total(!!), but who knows what amount for sure IN the plane.... and the main lenghened battery hatch/bay mod, with its strengthening gains, plus fibreglassing and a Flight Controller (Stabiliser).
But the least possible else than those things!

The first one was very good! And it is a very nicely designed and made plane - that flies great too! This one should be even BETTER!!

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Posted by PeterVRC | Apr 13, 2015 @ 08:50 PM | 1,761 Views
I finally gave in and got a "Twin"..... though I am not sure it was that great an idea....

Dynam make good 'cheap' planes, so I was confident this would also be in their typical style. And it is....
But as usual, as much as they have some great ideas and well thought out designs, there are things you can improve upon. Quite a few in this BF-110 as it turns out....

Another 'standard' of Dynam is the very average paint job they do. Very 'chalky' pastel colours, and the budget idea of painting the whole plane the underside colour (eg sky blue) and then ONLY adding the secondary Camo Scheme colour to the top where that goes.
But surprisingly, once this plane is coated in WBPU it dramatically transforms it into being a great paintjob finish!!

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Posted by PeterVRC | Dec 23, 2014 @ 07:24 AM | 4,508 Views
I had been keeping an eye on this jet for a LONG time!! I always wanted to get it, but anything from "LX" - also known as "Sky Flight" - costs a lot to get to Australia! Typically $300 to $340 for a kit version of their stuff! And that is not because it is 'good' stuff at all! In general LX (Lanxiang) have many weaknesses in each of their models. Things that are made too weak... fail... don't work properly.
This fact also makes the "$300 kit" a bit rich to even risk to get! But you can always 'fix' all the shortfalls..... and there is no other twin 70mm A-10 to get if you want that specific plane!

After LOTS of monitoring of forums about this LX A-10 I finally decided to RISK getting one, to see if it could be all 'fixed up'.....
AU$304 delivered.... that was using EMS post, and it took 7 days from order to the door. (Just the KIT remember!! sigh).

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Posted by PeterVRC | Dec 15, 2014 @ 05:45 PM | 2,966 Views
Time for a new jet..... ummm, not really - but I got one (two) anyway.
"But I don't have a swept wing single seat fighter... from the 40's - 50's... and that didn't have 'Super' in its name".....

The FlyFly models are always a great base to build upon! Though a LOT to do to complete them into a truly good model. In some ways it can be better getting some other decent brand PNF, except they always need CHANGES anyway! And this is pretty big - versus the Freewing 1200mm Sabre with its 80mm EDF.

Surprisingly it took FOUR DAYS, including the weekend(!!) to go from Order to my door, from China! Hobby88 are always reliable and prompt, though sometimes they can be a bit delayed in getting some models out the door and I think that is when they do not actually have one right there in a box ready to go. But nevertheless they are super service!
Shipping to Australia cost as much as the kit!!! Ouch!

Some pre-reading of forums and other owners info - done over the last year or so also(!) - gave me good ideas of what to expect and what I would likely do to mine. Quite a few mods to do, as is common here!

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Posted by PeterVRC | Nov 16, 2014 @ 07:12 AM | 3,178 Views
Ever since I had the Skyzone goggles I had seen they have a 'serious problem' with their Button layout.
With three buttons per each top end, for various control functions, they are quite raised 'domes' and thus very easy to press. You might think that is good.... but it is actually BAD!!
This is because you have to reach up to feel where they are, when you are using the goggles - or more importantly, there are times you grab up the top and you do not even want to touch them... but DO !! eg To adjust them on your eyes (eye-cups). Or even when you put them on, or take them down.

All of the buttons, except just the BAND button, are 'instant acting'. Click them and they do their task right away! Which means a number of possible cases of "I didn't really want that!" occurring. The two most disastrous being the CHANNEL button - changing a channel and you lose your FPV video link(!!), or the Internal Camera button toggling the view to be the goggles front camera instead of the FPV video feed!
I had actually changed Channel by mistake once when I was flying the PT-17 FPV and it was about 200 metres or so away!! I could only see a speck of it, but luckily my memory of where it was (seen in FPV mode) meant I could locate it in the air rapidly by LOS, plus then was VERY LUCKY that what I chose to do made it climb and enable me to lock onto WHAT it was doing very well. In 95% of cases losing FPV video would have been fatal and a crash really!

It is somewhat weird that...Continue Reading
Posted by PeterVRC | Nov 16, 2014 @ 06:45 AM | 3,146 Views
This is a 3 Axis DIY Head-Tracker as designed by Dennis Frie here:
http://www.rcgroups.com/forums/showthread.php?t=1677559

That thread is pretty straight-forwards... sort of... but it seems that some people still have problems building it and getting it working. All I can say is that I have built two, and both were very easy to make and worked perfectly right away. So if you make them 'properly'...... they work. And they work excellently too!

I have two sets of FPV goggles which both have Head-Trackers in them. But both are 2-Axis 'older' generation Head-Trackers. Just 2 Axis is not that bad, but the DRIFT and ERROR they have is totally unacceptable! It makes them almost unusable, seeing you have to constantly Reset the Head-Tracker's center point as you fly around - seeing they drift astray almost continuously!

This DIY Head-Tracker has 3 Axis support AND it never drifts any amount at all !
This is what you want in a Head-Tracker and thus makes it worthwhile to even have it as a unit you have to attach to the top of 'nice trendy and sleek' FPV goggles! Which ruins their good looks, but function wins over form!!

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Posted by PeterVRC | Nov 10, 2014 @ 11:51 PM | 3,324 Views
I decided to get a 'large' Flying Wing for FPV - because so many people say they are great for that!!
I bought the KIT version so I can fit the electronics and motor that I want.

I bought the Turnigy XP 3542-1000kv so that it has a bit more power than stock.
I am also aiming to run 3S and 4S 4400mAH batteries, with just a Prop change to use 3S or 4S.
For 3S I will use a 10x5 Aeronaut folding prop.
For 4S, and aimed for fast zooming around at shorter ranges, I will probably use about a 8x6 APC prop.

I will use an OpenLRS 433MHz RC TX/RX setup, but still just 5.8GHz FPV for a start - this might be able to do 5km approx max. Then I will get 1.2/1.3GHz FPV stuff later, to hopefully go out past 20km.
For long range I will carry a GoPro also - probably with a tilt only gimbal on the nose. Though maybe tilt/roll if I can fit that.

.......Continue Reading
Posted by PeterVRC | Sep 25, 2014 @ 08:54 PM | 5,198 Views
I am focussing only on 5.8GHz FPV setups so far. Maybe I will go to Long Range one day, but not for now....

After buying LOTS of various FPV items I have quite a lot of 'sub standard' items(!!) and some 'great' items! So I decided to make a list of what is good and what is NOT good to get!
What is "good" today might not be good tomorrow!! It is an ever changing world of electronics and FPV goodies!

I will just keep updating this thread as I go through more things over time.....
Posted by PeterVRC | Sep 24, 2014 @ 05:08 AM | 4,309 Views
There are some 'nuisance problems' with FPV Goggles that are perpetually annoying.

For all use:
1) A need for power - a battery that you need to fit or hold somewhere

For use with Head-Tracking:
2) A lead going to your TX
3) Having to press the Head-Tracker Reset Button, which are ON the Goggles, quite often.

After a bit of investigating and thinking I decided on a 'fix' for all of these issues in one swoop.....

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Posted by PeterVRC | Sep 17, 2014 @ 07:06 PM | 3,551 Views
For FPV there is quite a large range of options as to what Camera you use. So I will cover all the ones I have tried and what pros and cons each have.

List:
1) 808#16V2 (720p - CMOS)
2) Mobius (1080p - CMOS)
3) FH18C (520tvl - CMOS)
4) CAM5820 (380tvl - CMOS) with 20mW 5.8GHz inbuilt TX
5) Sony SuperHAD (600tvl - CCD) boardcam
6) Sony HADII (600tvl - CCD) minicam

I also have several pan, or pan/tilt setups - plus Headtracking via goggles or separate DIY unit, so I will cover those also.

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Posted by PeterVRC | Sep 10, 2014 @ 08:47 AM | 3,843 Views
After fun with the FPV250's I decided to get something a bit bigger, to carry decent FPV/Camera payloads and be able to do more 'useful' missions. More stable... more efficient... longer flying...

There are lots of cheap X Frames around, but this H frame stood out with a bit more character. It cost a bit more than many X's, but it can also fold up into a nice small rectangle - so it won out as my final choice of the many options there are.

I have not decided on what motors and ESC's yet - nor even the Flight Controller!
I am thinking APM, but next in line could be a KK2.1.... but it will be something with GPS and thus RTH and Waypoints capability.

I have to go and do some reading and assessing of what things to use with it.....

.......Continue Reading
Posted by PeterVRC | Sep 09, 2014 @ 09:45 PM | 6,557 Views
First lets go over a few “FPV Goggle’ details…..

In order to make the smallest possible unit (Goggles) designers have chosen to use two very small display screens – one per eye. If you were to use a single display screen it would need to be 3.5” at least, so that both of your eyes can see it all – because your eyes are spaced apart and separated by your nose!
So, now we have two very small screens, and we need those to be very close to our eyes – to keep the whole goggle unit ‘short’ and small. This means we need lenses to magnify what we see of the small screens, and they need to have a LOT of magnification! Also, the more they magnify the screen image, the larger a screen result we “see” – it is forming a Virtual Screen, like watching some large TV that is further away from us! That is pretty cool really!
The larger you want that Virtual Screen to be, the more magnification you need.

The lenses are already a very complex shape because they need to ‘convert’ a ‘round’ camera source – that is our eye – into clearly seeing a rectangular screen. This is a complex lens shape to create! It is also a very ‘thick’ lens, because of the complex shape and it needing to have a huge ‘convex’ curve for magnification. The more magnification the greater that curve must be and then optics get more and more difficult to produce with clear results.
Most are done in plastic. Some are done in glass (very few!).

The goggle Specs pretty well always give a FOV – Field Of...Continue Reading
Posted by PeterVRC | Aug 26, 2014 @ 06:19 PM | 3,796 Views
This is a continual electric models question.... and it never seems to get a solid answer! Though it is also possible there CAN'T be one fixed solid answer!

Question: "Can I connect multiple SBEC's outputs together?"

Note I said SBECs.... not BECs - being that a SBEC is still a BEC, it just specifies what type of regulator is in the BEC. The S means it is a Switching Regulator - as opposed to a Linear Regulator. (Maybe Linear BECs should have been called LBEC's long ago....)
I never use Linear BECs, as they are inefficient and can even be dangerous (to failure), so I am only concerned with SBEC's here.....

To be technically sound I pop the centre (red +ve) pin out of all SBECs/ESC's bar one and heatshrink over them so I can reverse that change easily in future if need be.
Though I am not ONE HUNDRED percent sure how much of an issue having multiple switching power supplies (SBECs) all feeding one point is.....

Say you have a quadcopter with 4 ESC's/SBECs.....
You would have 4 systems (SBEC circuits) that are highly likely outputting DIFFERENT voltages, eg Say one is 5.07v, one is 5.10v, one is 4.95v, one is 4.98v..... A regulator circuits work by feeding back the output to comparator circuitry so that it adjusts the output to be what it wants it to be, thus a constant loop correcting it to be 'right'. That 'right' value is whatever their components and trimming set it for. eg the 4.95v. Each ESC/SBEC will be a bit different in its output voltage aim...Continue Reading
Posted by PeterVRC | Jul 03, 2014 @ 06:48 AM | 6,487 Views
Another Glider !! A pretty big one!

When I fly my Fox 2320mm glider around, it is quite relaxing and somewhat fun really - versus the hectic pace of EDF jets, or even warbird prop aircraft. Seeing it is such fun I saw the FlyFly 4000mm DG-808S and decided I wanted a 'proper' thermaling glider, rather than just the Fox sports glider. Having 'just' TWO gliders isn't being too greedy! (??)

The DG-808S is a Composite fuselage, and Balsa Sheeted wings and Tailplane that are covered in some form of Monokote = all of it is a shiny white finish, much like any real glider is. NOT "just" an EPO foam glider, like the Fox is. Not that foam gliders are really anything sub-standard at all, but you are unlikely to get a 4000mm (or even 3000mm) foam glider.

I read up a lot about it, as per I do for all aircraft before committing to buying any, and it seemed it was a very good buy. Such a large glider for its price, though AU$320 delivered seemed a lot to me! But many people are paying AU$400 at least, and out towards AU$1000 for some! So this is a BUDGET way to get a 4000mm glider!

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Note the 5/10 Rating now......
I did this because of the very weak fiberglass fuselage, and even worse 2K paint they have on that! The fuselage is plain/raw fiberglass - not Gel Coated fiberglass - which is then spray painted with 2K paint. This paint is very 'rigid' brittle stuff, whilst the fiberglass is NOT! Thus it is quite easy for any flex in the fuselage to cause the 2K paint to...Continue Reading
Posted by PeterVRC | Jun 20, 2014 @ 10:38 AM | 7,044 Views
A QUADCOPTER!!!
Well, I did have a weeny 4" one for indoors already. And had another 4" one a year or two ago....

This all started when a friend 'made' a 600mm Quadcopter, but has no idea about electronics, RC stuff etc.... so I offered to set it up and get it going. That was fun!
I already had helicopters (300, 450, 500) years ago, so I knew how to fly these things anyway, though it was still a bit 'new' and I had not flown a helicopter in over 6 months either.
Buzzing around I then decided to put my FPV gear onto it and learn that.
About that same time I ran into a few guys with quadcopters and seeing theirs (FPV) racing around it made it even more interesting!

So the two sources 'merged' to lead me into getting a 250mm FOV spec racer type. Firstly because of what those other guys had, but also when I saw HobbyKing had a kit for $110 !! Versus 'good' ones can be $250 to $500 ! Yet reviews on the HK one (a Diatone brand frame) were good too.
I also had a KK2.0 flight controller already from a year or two ago, so that meant I would finally pout that to good use too! That was a good excuse to throw into the mix!

The kit turned up on Wednesday.....

.......Continue Reading
Posted by PeterVRC | Jun 20, 2014 @ 10:02 AM | 4,685 Views
Over the 5 or so years I have had a LOT of batteries! Too many to count really!
Too many failing to count too!

Because batteries cost a lot in Australia, the 'cheapest' way to get them is via HobbyKing Aust, seeing they ship by sea in quantity and then the cost to the buyer is lower by some amount. BUT they do not have any good/great batteries really!
Zippy - very average, if just.
Turnigy Blue - average
Nanotech original - dubious
Nanotech A-Spec original - great! (and costly)
Nanotech A-Spec G2 - I didn't risk buying any because reports on them are poor!

The biggest failure is "dropping a cell", or few.....
If you overstress a battery - running at very high currents, over what it can do viably, AND/OR overheat them - whether puffing or not - then they can be permanently damaged. And fairly easily too!
This is very EASY to do with EDF aircraft!! But still occurs in prop aircraft too - just not as often, seeing they run way less relative power (Current/Amp) levels.

Worse is when they fail for NO reason of over-stress or anything known! And that is too often! This is possibly because the HobbyKing range are NOT very good batteries really. None of them, bar the A-Spec original. Not cell matched well (though they claim they are) and poor QC overall I would say. Thus sub-standard cells get into the total set of battery cells often enough.
So maybe buying TRULY GOOD brand batteries is better????

ThunderPower are supposed to be 'great', and COST a LOT.... but...Continue Reading
Posted by PeterVRC | Apr 18, 2014 @ 07:48 AM | 5,175 Views
I will finish this more later.....

It has finally come to light how there is a big issue with being tail heavy!
Not the usual 'It will be hard to control', 'It will be over-sensitive', though they are still true also..... but the 'Stuck in a hover" potential, which will leave a plane with no ability to exit from that!!

I must have been a bit slow to co-relate the data (!!), but via an F-35, F-22 and F-4, all encountering that BIG issue, it finally all makes sense!
If you are tail heavy beyond "Point X" - and that does not mean a "ton", it could be just 10mm more rearwards CofG, or whatever, per a given plane - once the plane pivots into an AoA greater than "Angle Y", it will reach an equilibrium of factors that KEEP it there!
High AoA... like 70deg or more... which then causes huge drag.... needs max power just to stop it falling out of the sky.... has no 'proper' airflow over control surfaces, so they become TOTALLY inefficient and have no authority at all then.
So it is then STUCK in this state, because nothing you have control over can achieve anything - except reducing/cutting power which will make it descend if you do that correctly... or totally stall out and fall out of the sky if you do not!
And I mean it is STUCK there..... it is not going to slowly come out of it... because the equilibrium of all factors is just right to sustain it, and as mentioned there are no controls YOU have to alter that.
A gust of wind might be...Continue Reading
Posted by PeterVRC | Apr 11, 2014 @ 11:42 PM | 6,249 Views
Seeing I have a few 7S powered aircraft now, SPARKING when you connect a battery up is a notable issue. Connectors get charred... their tips/edges eaten away by the fusing... and it can't be good for ESC's really.
This issue really begins at about 5S, and by 6S it really is a problem that should be dealt with. Then 7S upwards... DEFINITELY needs attention!

An Anti-Spark system is just a method of making a Battery to ESC connection WITH RESISTANCE in-line so that the ESC Capacitors do not charge up in "An instant" and thus draw a huge amount of current at that instant - that "Instant' being the split second your connectors first touch each other the slightest bit! And that is what causes that "Arc Welding" spark!
Theoretically, a Capacitor connected to a Voltage source, with zero resistance in-line, will charge INSTANTLY.... and the 'opposite side" of that is that the current level will be INFINITE for that micron in time! Of course the battery can only supply X Amps.... but at 6S levels that could be 200 Amps+ !! Luckily it is only for the micro second!

You can buy some nice connectors these days that have the Anti-Spark Resistor system built into them. So for $8 to $10 or so you can have a very easy solution.
For now I am using a home-made system... outlined below. It costs under $1 per plane....