Originally Posted by nigelsheffield

I would love a job developing stuff like that, I started out as a electronics enthusiast in my teens and then got a job in tv repairs lol with radio rentals and after 6 years started my own repair business, I have made a few things hear and there over the years but now things are so small my eyesight is not good enough to see the components let alone build them all together lol.
But I think I would make a good ideas man and have something to say about design and impementaion and be part of a team, done some programing in past to but trouble is I can't spell right well and so would need to use spellchecker quite a lot lmfao.
So, any one out there want to give me a job "I'M FREE".( well quite cheap anyway lol).
Nice day out today again just very cold might go for a flight now catch you later hope the weather breaks for you too soon.

Who knows? Perhaps you might find what you are looking for. I note that there are many brilliant guys on these forums. Guys with engineering minds, oodles of creativity and problem-solving abilities that are as good as anyone on the planet. That's part of what I like about hanging out with you guys... you inspire me!

Our storm dumped 1.5 feet of snow and left us about mid-day today. I spent some time shovelling then took a long nap on the recliner with my faithful Wheaton Terrier asleep in my lap. Going to organize my hobby materials tonight in advance of commencing another build tomorrow.

All the best from Colorado,

Jackson

Originally Posted by nigelsheffield

that looks a better solution then a ubec because if you draw too much currnet from a ubec they seem to blow completely, bit expensive though but I suppose if it saves a plane its worth it. I replaced the esc in minimoa with a hobby wing 30 amp esc as I wanted to reprogram it to nimh anyway and esc does not get warm, in the ask21 I still have original esc and that get very hot and needs 5 min cool down between flights and once a servo connector went dodgy and shut the rx down several times b4 the servo stopped and and I regained control and managed to land( with one aileron stuck down at 45 degree angle) so stock esc is not very good.

I even bought the $27 USB program card that is used with CC ESCs. That is to change things but I may not need to change anything.

I have not used it or the CC ubecs as yet. I have a good balsa Yak54 my daughter bought me and have flown it just with a Turnigy 60amp Plush ESC (3amp BEC) but I think it might be all right (hopefully) with the 5 servos.

Guess I should put this CC UBEC in with the 60amp ESC.

Originally Posted by Galand

Actually these Castle CC BEC's are the luxury epitomy of a UBEC defined as a separate BEC i.e. not part of an ESC.
Their blurb correctly criticizes the linear BEC's usually found in ESC's but does not say whether this one is linear or switching.
There is a wealth of BEC info to be found in this thread by Galaxiex:
http://www.rcgroups.com/forums/showp...89&postcount=1
Specifically on the CC 10A BEC:
http://www.rcgroups.com/forums/showp...5&postcount=44

It is hard to see if it is a SBEC or not but I guess it does not matter as all reports are good. I just read the instructions that came with it and it says CC BEC switching power regulator. So I guess it is a SBEC but they do not state it much.

Do not buy this one as they are rubbish:
http://www.hobbyking.com/hobbyking/s...for_Lipo_.html

Here is more info on BECs unless it is what you included in your links:
http://www.rcgroups.com/forums/showthread.php?t=1277428

the trouble with swtching ubecs is that they need some sort of over currnet protection built in other wise if too much current is drawn due to a s/c the swtching transistor simply destroys itself, this was the case when I was fixing tvs back in the days when switched mode supplies were a new invention and we all had to go on a 3 day course to find out how they worked and how to go about fixing them, where as a really good 5v reg with a supply resistor would generally survive or maybe just burn out the resistor.
Also the process of switching the transistor many many times per second and controlling the pulse width is a complicated one and as we all know the more complicated something is the more likely it is to go wrong, not what I want in the the main 5v supply to my rx.
So I personally would prefer a high rated bec over a ubec any day.

I'd be using the Castle Creations but they must have good current protection built in. I understand the blokes with the big expensive planes use them.

The built in BECs are only border line for some planes so that is why I'll use these. A decent 5amp one would do but I'll use the 10amp one as it is only small.

I guess I am only just getting away with it in my balsa Yak54 with 5 servos and a Turnigy Plush 60amp ESC which has only a 3amp BEC.

I dug this up elsewhere if it is of any interest:

"A BEC (battery eliminator circuit) is typically built into the ESC (electronic speed control) and by modifying the voltage from your flight battery (typically 2s -7.4v or 3s 11.1v) delivers power for your Rx and servos at ~5v (but usually no more than 2A-3A). (PROBLEM)

If you go to 4s (14.4v) or more, and have more than 3-4 servos, the usual linear BEC in the ESC cannot cope with reducing the high voltage down to the ~5v the Rx and servos need, nor can it deliver enough current to power many, especially digital, servos.

Then you need a stand alone UBEC (Universal BEC) which is typically a switch mode unit which is capable of reducing the voltage from 4s+ packs to the required ~5v, and can deliver as much as 10A to power many, big, digital servos and your Rx.

That ESC you link to is an Opto, so it has no built-in BEC... you will have to use a UBEC or carry an additional battery pack (4.8v-6v) as a power source for your Rx and servos. "

Originally Posted by nigelsheffield

the trouble with swtching ubecs is that they need some sort of over currnet protection built in other wise if too much current is drawn due to a s/c the swtching transistor simply destroys itself, this was the case when I was fixing tvs back in the days when switched mode supplies were a new invention and we all had to go on a 3 day course to find out how they worked and how to go about fixing them, where as a really good 5v reg with a supply resistor would generally survive or maybe just burn out the resistor.
Also the process of switching the transistor many many times per second and controlling the pulse width is a complicated one and as we all know the more complicated something is the more likely it is to go wrong, not what I want in the the main 5v supply to my rx.
So I personally would prefer a high rated bec over a ubec any day.

I f you are flying a big plane with more which can carry a bit more weight a separate rx battery is the way to go, either nimh, a 2 cell life type battery, a 2 cell a123 pack 1100mah weigh 40g per cell, 2300mah weigh 70 g per cell and you wont need any bec, or a 2 cell lipo with a 5v bec rated for the amps you need.
But getting back to this plane the supplied esc is only just enough for this plane and best replaced with a 30amp or more with a 3amp bec or more, or a quality ubec.
Hobby king sell some life cell rx batteries that are quite small and light and might be ok as a separate supply bu tof course you must then charge up your rx battery too or your gonna crash when that runs out lol!

Originally Posted by nigelsheffield

I f you are flying a big plane with more which can carry a bit more weight a separate rx battery is the way to go, either nimh, a 2 cell life type battery, a 2 cell a123 pack 1100mah weigh 40g per cell, 2300mah weigh 70 g per cell and you wont need any bec, or a 2 cell lipo with a 5v bec rated for the amps you need.
But getting back to this plane the supplied esc is only just enough for this plane and best replaced with a 30amp or more with a 3amp bec or more, or a quality ubec.
Hobby king sell some life cell rx batteries that are quite small and light and might be ok as a separate supply bu tof course you must then charge up your rx battery too or your gonna crash when that runs out lol!

I realise that you can put a old fashioned NjHi battery pack for the receiver but never thought of it for my YAK. Weight is not a problem but just got to make sure it is charged fully.

Guess that would take all the worry out of it and I have a good Eneloop rechargeable pack.

I think the Minimoa ESC is right for 99.99% of the time but you do not know when the .01% will come up and lock on a servo. So with .01% some people will never experience the problem but you never know.

Originally Posted by Firepower

I realise that you can put a old fashioned NjHi battery pack for the receiver but never thought of it for my YAK. Weight is not a problem but just got to make sure it is charged fully.

Guess that would take all the worry out of it and I have a good Eneloop rechargeable pack.

I think the Minimoa ESC is right for 99.99% of the time but you do not know when the .01% will come up and lock on a servo. So with .01% some people will never experience the problem but you never know.

Firepower,

Do you have the Hobby King 1280mm Yak 54? If so, I have the same plane. I love the way it looks and handles, but the landing gear is too weak. I have a 120mm carbon fiber gear replacement coming from HK. BTW, I have a separate UBEC in the Yak along with a 60 amp Emax ESC, plus an Orange 6ch RX and satellite RX antenna. My TX is a Spektrum DX8, which I really enjoy. I have had good luck with the Orange Rx's as long as I have used UBECs for high-load scenarios (i.e. many servos), especially with 4S batteries. The HK Yak is powered by a G25 brushless 870 kv outrunner and really tears up the sky.

I replaced the ESC in the Minimoa with a 32 amp PowerUp ESC. This ESC just gets warm with steady use of my 165 watt motor/prop combo. The built-in 2 amp BEC seems to to handle the load of 4 servos without problem on a 3S 2200 mAh battery.

Cheers,

Jackson

Hi Firepower,

I checked your blog and realize your Yak is not the same as mine, although very similar. You can see mine in the photo under my name on the left. It is also at http://www.hobbyking.com/hobbyking/s...80mm_ARF_.html

I see you have a very impressive collection of planes, gliders and flying wings. Lots of "firepower" in the event of aerial attack by rogue RC drones. Haha!

Best regards,

Jackson

Originally Posted by Jackson Stone

Firepower,

Do you have the Hobby King 1280mm Yak 54? If so, I have the same plane. I love the way it looks and handles, but the landing gear is too weak. I have a 120mm carbon fiber gear replacement coming from HK. BTW, I have a separate UBEC in the Yak along with a 60 amp Emax ESC, plus an Orange 6ch RX and satellite RX antenna. My TX is a Spektrum DX8, which I really enjoy. I have had good luck with the Orange Rx's as long as I have used UBECs for high-load scenarios (i.e. many servos), especially with 4S batteries. The HK Yak is powered by a G25 brushless 870 kv outrunner and really tears up the sky.

I replaced the ESC in the Minimoa with a 32 amp PowerUp ESC. This ESC just gets warm with steady use of my 165 watt motor/prop combo. The built-in 2 amp BEC seems to to handle the load of 4 servos without problem on a 3S 2200 mAh battery.

Cheers,

Jackson

My YAK is the same wingspan as yours. Mine took almost a year to finish because (I am slow) the fittings were rubbish and I have to get others. I'd say yours would fly the same as mine which is great.

The design of the steerable tail wheel, bolts to hold it together etc etc were a hold up. My mate got a Katana at the same time and everything was made much better. Hope yours was good.

I was lucky and started with blokes with Futabas and ended up with a second hand Futaba 9C.

You probably saw this I put up recently which mainly means make sure you do things right with the receiver voltage..
http://www.rcmodelreviews.com/dsm2flaw.shtml
http://www.rcmodelreviews.com/spreadspectrum01.shtml

Now I know this is for DX6i is DSM2 but yours is a DX8 so is that a DSM2. I guess if it is you have to keep your RX/BEC voltage up.

You say your new ESC in the Minimoa is 32amp with a 2amp BEC.

It is good you increased it to 32amps but I think the problem is the 2amp BEC. The old standard ESC had a 2amp BEC and that was the problem so have you really improved your ESC with that one.

I am trying to concentrate on FPV and have recently had some good flights after working at it for over two years. The recent gear is much better than two years ago. I have the FY21 and Eagle Tree stuff that brings the plane back when you get lost but it all takes time to get that going. But after buying this stuff and two FY20s which I have got going perfectly, really found out they are not necessary to start FPV flying. I thought I need the FY20s with gyros to help me keep it in the air but have flown FPV recently without them with no problems.

So my Minimoa is on the back burner at the moment.

Good one on the Firepower comment. I guess no one can see what the avatar photo is. It is a photo of the back glass of my Firepower 2 pinball machine. It is nice artwork of delta winged jets but you can not really see them.

Col

Originally Posted by vtdiy

Just points of possible interest, the 11x7 on 2 cells WOT is about half the waste heat of the 9x5 on 3 cells. The ESC is rated 20 amps continuous and the above combo is only drawing 12 amps through it, so there is a very good margin.

Hello All.

I just received a new Minimoa from HobbyKing. I had read about halfway through this thread when I ordered it with a couple of 2S, 3300mAh LiPos to address heat/power issues with the originally supplied 11x7 props.

Now come to find later in the thread that the Minimoa is now shipping with 9x5 props, though mine actually measure about 9.75" (4.125" blades and 1.5" between the spinner pivots).

So... do I go back to 3S batteries or order the original 11x7 blades (or maybe swap with someone here who has virgin 11x7s they're not using)?

Like Mr. Stone, I will be flying at 6000+ feet here in Colorado, and I know the power will be marginal, but I'm still inclined to go with my original plan of running 2S with the larger prop.

What say you all, and where can I most easily get the 11x7 blades if that's the verdict?

Thanks,
Dave

P.S. I'm a noob flyer, and will not be flying the Minimoa for some time yet. I'm still practicing with the HZ Champ (54 flights with no crashes - knock on wood ), and then will probably be getting some instruction on the Airfield Skytrainer 182 I'm building now. I just couldn't resist the Minimoa's good looks, and had to get one.

P.P.S. The Skytrainer runs on 3S, 2200mAh LiPos, so I could potentially use those in the MiniMoa with the smaller prop and some venting/exhausting. In any case, I'd like to make the stock motor/ESC work as reliably and effectively as possible for the time being with minimal mods.

Originally Posted by Firepower

My YAK is the same wingspan as yours. Mine took almost a year to finish because (I am slow) the fittings were rubbish and I have to get others. I'd say yours would fly the same as mine which is great.

You probably saw this I put up recently which mainly means make sure you do things right with the receiver voltage..
http://www.rcmodelreviews.com/dsm2flaw.shtml
http://www.rcmodelreviews.com/spreadspectrum01.shtml

Now I know this is for DX6i is DSM2 but yours is a DX8 so is that a DSM2. I guess if it is you have to keep your RX/BEC voltage up.

You say your new ESC in the Minimoa is 32amp with a 2amp BEC.

It is good you increased it to 32amps but I think the problem is the 2amp BEC. The old standard ESC had a 2amp BEC and that was the problem so have you really improved your ESC with that one.

I am trying to concentrate on FPV and have recently had some good flights after working at it for over two years. The recent gear is much better than two years ago. I have the FY21 and Eagle Tree stuff that brings the plane back when you get lost but it all takes time to get that going. But after buying this stuff and two FY20s which I have got going perfectly, really found out they are not necessary to start FPV flying. I thought I need the FY20s with gyros to help me keep it in the air but have flown FPV recently without them with no problems.

Col

Hi Col,

First of all I recognize you in your article/website from the YouTube videos that you posted on how to build a Floater Jet. I watched the videos carefully before building one around Christmas time and found them incredibly useful. I built the Floater Jet for a friend of mine. Thanks for that good piece of work; I popped $25 into your paypal as my token of appreciation.

Second, I hear that you think my 2 amp ESC is a problem waiting to happen. I happen to have a 3 amp UBEC sitting on my desk. Do you think I should pop it in? Would be easy to do.

Third, I do love the way the Yak flies. So fast, maneuverable and powerful. It really keeps me on my toes!

Last, I am thinking of venturing into FPV this year myself and have a friend who is pretty bright with all that stuff who is acting as a pathfinder from me. One thing I did get out of your article is that I should avoid using a 2.4 ghz video tx because of its massive frequency footprint over my 2.4 ghz Spektrum Tx signal.

Thanks for the indepth response, and appreciating my humor on the Firepower remark.

Cheers,

Jackson

Originally Posted by BrundleFlyBy

So... do I go back to 3S batteries or order the original 11x7 blades (or maybe swap with someone here who has virgin 11x7s they're not using)?

Like Mr. Stone, I will be flying at 6000+ feet here in Colorado, and I know the power will be marginal, but I'm still inclined to go with my original plan of running 2S with the larger prop.

What say you all, and where can I most easily get the 11x7 blades if that's the verdict?

Hi Dave,

Nice to hear from a fellow Coloradoan!

My first thought is just test your existing system with the 2S batteries and see how many watts you are drawing. My system draws 165 watts and provides ample power for flying the Minimoa at 6,400 feet. If yours draws less than 150 watts, it might be a good idea to step up to the larger blades. Unless someone responds to your request a good place to get blades is Headsuprc.com .

Good luck with your flying. If you would like to get together and fly the Minimoas in formation let me know.

Cheers, Jackson

Originally Posted by BrundleFlyBy

Hello All.

I just received a new Minimoa from HobbyKing. I had read about halfway through this thread when I ordered it with a couple of 2S, 3300mAh LiPos to address heat/power issues with the originally supplied 11x7 props.

Now come to find later in the thread that the Minimoa is now shipping with 9x5 props, though mine actually measure about 9.75" (4.125" blades and 1.5" between the spinner pivots).

So... do I go back to 3S batteries or order the original 11x7 blades (or maybe swap with someone here who has virgin 11x7s they're not using)?

Like Mr. Stone, I will be flying at 6000+ feet here in Colorado, and I know the power will be marginal, but I'm still inclined to go with my original plan of running 2S with the larger prop.

What say you all, and where can I most easily get the 11x7 blades if that's the verdict?

Thanks,
Dave

P.S. I'm a noob flyer, and will not be flying the Minimoa for some time yet. I'm still practicing with the HZ Champ (54 flights with no crashes - knock on wood ), and then will probably be getting some instruction on the Airfield Skytrainer 182 I'm building now. I just couldn't resist the Minimoa's good looks, and had to get one.

P.P.S. The Skytrainer runs on 3S, 2200mAh LiPos, so I could potentially use those in the MiniMoa with the smaller prop and some venting/exhausting. In any case, I'd like to make the stock motor/ESC work as reliably and effectively as possible for the time being with minimal mods.

You will definitely be better off with the 2 cell 11*7, it will run cooler and be more efficient, and if your still a bit weak on power due to altitude you could go to 3 cells and limit your throttle as has been mentioned b4.
I have used the 3 cell 9*5 set up and found esc and motor to get so hot that I can not hold them after just 1 flight using 3:20 mins of full power in total and a flight of about 18 mins.
Now I use 3 a123 cells which are closer to 2 cell lipo at around 8.4v under load and a 10*6 folder and esc and motor just get slightly warm but barely any warmer then b4 I flew, this set up is very close the nimh batts that this plane was designed for originally.

Originally Posted by Jackson Stone

Hi Col,

First of all I recognize you in your article/website from the YouTube videos that you posted on how to build a Floater Jet. I watched the videos carefully before building one around Christmas time and found them incredibly useful. I built the Floater Jet for a friend of mine. Thanks for that good piece of work; I popped $25 into your paypal as my token of appreciation.

Second, I hear that you think my 2 amp ESC is a problem waiting to happen. I happen to have a 3 amp UBEC sitting on my desk. Do you think I should pop it in? Would be easy to do.

Third, I do love the way the Yak flies. So fast, maneuverable and powerful. It really keeps me on my toes!

Last, I am thinking of venturing into FPV this year myself and have a friend who is pretty bright with all that stuff who is acting as a pathfinder from me. One thing I did get out of your article is that I should avoid using a 2.4 ghz video tx because of its massive frequency footprint over my 2.4 ghz Spektrum Tx signal.

Thanks for the indepth response, and appreciating my humor on the Firepower remark.

Cheers,

Jackson

I think you have the wrong person as I have not put on youtube how to build a Floater Jet. I did not know you can make money that way or I might try harder one day.

As you will see right through the Minimoa forum the 2amp BEC in the old ESCs are not high enough.

But sometimes a 3amp UBEC can be worse than what you have. Do you have a make and model of it? Everyone will tell you something different as everyone have their favourites but for the cheaper planes I use Turnigy Plush ESCs. But I just looked at the 30amp Turnigy Plush and it only has a 2amp BEC which is no good:
http://www.hobbyking.com/hobbyking/s...ontroller.html

So if weight is not a problem I would use this one:
http://www.hobbyking.com/hobbyking/s...ontroller.html

Like I said others have their favorites and maybe they can recommend a 30amp ESC with a 3amp BEC but I would put a 40amp Turnigy Plush in which I have. I did not know anything about the UBECs when I put it on and my UBEC is about just under 10% better than the Turnigy BEC.

Before you buy any FPV stuff you could PM me and I can let you know exactly what to buy. I also understand your frequencies that you use over there are different to here. I have been lucky and have been frying with mates with all the good gear including UAV stuff.

One day one of them threw his wing and it disappeared over a massive shopping complex and he put the TX on the ground. When it got the fixed distance it turned around and flew over 16 way points and then circled above.

I have spent a lot of money on FPV over the years but if starting now it is very cheap.

All the best.

Col