GliderIreland - Ireland RC Forum - Flying Model forum in Ireland
Techniques => Radios => Topic started by: Fred on April 29, 2010, 10:46:40 AM
-
Alright, finally joining a few people in the XXIst century !
I finally moved my good old MC18 from 41Mhz to 2.4ghz using a Corona DIY module...
Install took 10 minutes, and so far, working great, but real test will be at the slope ! Weird not to have this huge antenna in front of me ! :D
Never had any issues in 41 or 35mhz, ever, but now, I fear other people on the slope, as it seems that there is a general assumption that everybody is in 2.4, and will turn on 35mhz gears without checking with the other guys at the slope, and true or not, flying machines that can kill people very easily, I have to try this new stuff now that early problems seems to be ironed.
Anyway, let's try that thing with crunchies and do all possible tests before putting that in bigger stuff !
Only 3 receivers for now, we'll see, as I might move to Jeti if I go for the big jump ! :D
(http://www.gliderireland.net/forum/images/uploads/Fred/P1010628.JPG)
-
Now you’re really “Cooking with Gas” Fred! :clap:
I’ve only ever used 2.4. Never had any interference problems and never had to be concerned with what other pilots are using. (Nor have I had to worry about poking other peoples eyes out with long antennas!)
Welcome to the modern world :D
K.
-
Hey Keith, thanks :D
Getting there, slowly, but surely !
But I have to admit that it is hard to change a perfect working reliable system ! Must get old :P
And I think the RC manufacturers are doing a lot of money with that ! This is old cheap technology, sold the price of gold to us :!: :!:
Ah well, I'll test that thing to the max, and we'll see !
-
Hey Fred,
What took you to go for Corona?
Not choosing Spektrum I have several reason and the biggest is the €'s.
Most of the people I know have gone for Assan, so It will be good to know how the Corona perform.
Nando
-
Hi Fred,
don't be afraid. i went for Jeti this winter and don't have any problems. Works great and feels reliable. Made it switchable between 40 Mhz and 2G4.
The biggest problem for me was not having any more the long Antennae in front of me. Sometimes I lost my orientation :lol:
Regards
Lothar
-
Hey Fernando,
I went Corona because it is dead cheap !
I know they had lots of issues in the past with their 2.4ghz gears, but new test etc etc on RCGroups and other people I know, find the new DSSS stuff flawless !
Some guys on RCGroups, with a simple TX antenna update (cost 10 euros...) managed to have a 7.5km range ! In a mountain environment!
If that work as good as their current 35mhz gears, I will be more than happy ! :D
Hi Lothar :D ,
For me, it's more in my mind ! Why changing a system I use for the past 26 years without a glitch (and I mean never!) for something that will provide me with the exact same thing, but at the cost of a few new models in money...
But I agree, it's a great peace of mind while flying not having to worry for people switching TX in your back :D
And without the big antenna, I now lean back when flying ! :P
-
Oh, and I think, in a while (read, when the prices will go down :roll: ) I think I will move too to Jeti ! Great reviews and fonctionalities, and well placed price wise :D
-
By the way... :wink:
The box and content :
(http://www.gliderireland.net/forum/images/uploads/Fred/P1010612.jpg)
The 2.4ghz module... And where to solder the antenna :!: :!:
(http://www.gliderireland.net/forum/images/uploads/Fred/P1010614.jpg)
I used servo connectors at the other end.
(http://www.gliderireland.net/forum/images/uploads/Fred/P1010620.jpg)
The radio opened.. The 41mhz module on top :
(http://www.gliderireland.net/forum/images/uploads/Fred/P1010622.jpg)
And removed. You can see the pins to use for the 2.4ghz module. At a later stage, I will certainly put a bipolar switch to allow me to switch between 2.4 and 41mhz... Or at least, I'll do it when I'll move to Jeti on the 3030...
(http://www.gliderireland.net/forum/images/uploads/Fred/P1010624.jpg)
Et voila !
(http://www.gliderireland.net/forum/images/uploads/Fred/P1010626.jpg)
The binding switch etc are inside the radio. I will make it on the front panel of the radio later, but that is still really easy to access, and a window allow me to see the operating light anyway.
(http://www.gliderireland.net/forum/images/uploads/Fred/P1010629.jpg)
Next stage, in flight ! :D
-
Very neat job Fred. :D
Question: How do you range check with the 2.4 module?
K.
-
Thanks Keith,
Good question actually, that I asked myself yesterday !
I removed the antenna and went to the garden (rx in the garage) and still had a link...
Not too sure what that mean, but my plan is to go in Mt Leinster, go to Nine Stones, and drive down to the West slope and check the range from there ! If working fine moving the glider around, in the wood, and behind the car, I'll be happy, as at this distance, even a 5 m glider will be really small !
Not too sure of the distance on a straight line here... Maybe a mile ? Maybe a bit more ? :?: So more than enough, even for thermal flying :D
-
Fred, I wouldn’t try using the module without an antenna…………. That might cause the output stage (P.A. stage) of the module to blow. :shock: (high voltage Standing Wave Ratio,…….and all that jazz)
I suggest you consult the manufacturers and ask them how to reduce the power for range testing. I would think there would be some way of reducing the power, or shielding the antenna, :?: for the purpose of range testing.
K.
-
No, no way of reducing the power. Not a surprise for a 20 euros module really :D
I'll do the range check in Mt Leinster, at least, I'll know live, and in real situation !
-
Alright, here is a quick report about this cheapo 2.4ghz system : it works ! :D
Ok, so Sunday, went to the big L. The Easyglider fully charged with the Corona receiver inside. Note that, to push the test to the max, I did not bther putting the aerials at 90 degrees and all that! I just put the receiver as it is, slided under the wings in the canopy, so basically, the aerials where more or less twisted togeter, and bent over the receiver ! Like a pig, in purpose !
And did not bother with a range check, just launched the glider as it came... And flew as far as I could see the thing, in all positions possible, and no glitches or loss of signal !
Not bad for a 20 quid module/receiver !
So, flew most of the day with the EG, and no problems at all !
But, with Keith, we pushed a bit further the test... During a bit of rain, I standed behind Keith, the TX aerial glued to his back (jacket all wet by the rain), and the EG, in the cloud !
Had a few glitches (the movements of the controls were a bit like that was step by step) but I never loss the signal at any moment ! And all went back to normal when I moved from behind Keith... A bit extreme situation, but all went great !
Conclusion : It works ! Not bad at all even, but I want to push that thing further. Next, receiver in the Alpina... But before I'll do a proper range check and stick to the plan to leave the TX at 9 stones, and drive down to the West slope.. If I still have signal there, well, all good ! (that's at least a mile away...)
Stay tuned ! :D
-
That is great news., but let me note than down... "never let Keith pass on my front with a wet jacket..." :lol: :lol:
Btw I'll post here a nice link that shows some tests on 2.4Ghz regarding signal quality and lockouts. They tested the antenas is several positions.
The system used was from Assan but for the purpose it doesn't matter.
http://www.flyelectric.ukgateway.net/24logger.htm
-
An interesting site Nando. :?: Thank You. :clap:
It shows the importance of having the rx antenna's at 90 degrees to each other. It’s a pity not all the tests were done with the same flight pattern. (Some were climbs and descents, other tests were done while flying aerobatics,……..but interesting statistics none the less. :) )
Incidentally, it wasn’t my wet jacket that attenuated the signal from Fred’s Tx so much as the fact that my body, which is 90% water. (Or in Ed's case, 90% alcohol. :lol: ) And the signal had to pass through me to get to the plane. (Remember also that Fred did not have the rx antennas at 90 degrees to each other.)
Thanks again for the link
Keith
-
Oh, on a side note, I did not noticed to be more "in touch" with the glider...
The t8z is 1024, and to be honest, no differences at all.
We'll see with tha Alpina next.
-
Fred,
T8Z? Futaba?
Most futaba if not all only do 1024 or 2048 (new ones) when using PCM on PPM they do 512
and only use only 8 chn. :( So if you're using the corona module you'd need to be in PPM and stuck in 512.
Could be this why you didn't noticed any difference?
Keith,
I particularly enjoyed the tests regarding using 1 or 2 antennas. There was much fuss going around because one of the antennas in the Assan modules are connecting to ground, and on the micro rx's they have only one. So the assumption was that the second one was there only for decoration or to look like the Spektrum modules.
If those tests are correct they indeed seem to help on the noise filtering.
If you like those articles I can get you tons. In Portugal the 2.4Ghz usage is still not very well defined and for quite some the discussions ended in collecting loads of information about the several systems offered.
-
I doubt that the “extra” antenna is for decoration purposes Nando. Most antennas have a “grounded” side. The grounded part improves the reception of the whole antenna system.
I imagine the rx with only one antenna wire is for short range, possibly indoor , use only.
It’s been many years since I studies matters such as the Law of Antenna Reciprocality, and the inverse square law of power over distance. :roll: God, doesn’t that sound sooooooo boring! I’m not sure if knowing all the above makes me a Geek, or a Nerd. :oops: What do you think?
K.
-
Hey Fernando,
For the resolution of the Ct8Z module (sorry, missed the C in the module name! :oops: ), according to Corona, and a few guys on RCGroups, this is a 1024 system (Same for all the DSSS stuff it seems :?: ), but I have to admit that I don't have a clue, I'm just a basic user of that stuff :?
Keith ---> You're a geek ! :P
-
Keith,
I admit I had no opinion on that. For me radio frequencies and related matters is a strange world, don't fit in my limited electronics knowledge.
But I was smart enough not to cut the extra wire. :-)
+1 for Geek.
Fred,
Well the idea that i had was that ti depends on the radio, receiver and servos.
They have to be able to work with the 10bits resolution to get the 1024 steps resolution, but I'll check that out.
I leave here another link in case you guys don't know it.
http://www.rcmodelreviews.com/corona_dsssv2.shtml
This is a review to the Corona system.
This guy performed the sames tests to other brands as well and have some really nice videos on youtube about the tests.
-
Just back from the slope, testing my new 2.4ghz system with the good old EasyGlider :D
After I sold my Corona system, started to look for a new one... Didn't had to look far as I already saw the system made by FrSky and was impressed (and so a lot of other people!) with the specs of their product.
2.4ghz system, ACCST (like FASST), and cherry on the cake, telemetry!
All that for about 50 euros :D
So, played with it for a little while, and today, made the first flight.
There is a range check function, and in low power, had about 40 mtr range (that's a bit more of 2 miles range at full power in theory).
As expected, like the Corona system really, no problem at all! Did not manage to fault the system whatever I tried!
Telemetry now... You have a range alarm, and a RX battery voltage by default. The good thing, is that the telemetry protocole is open source! Lots of stuff is being made, like a vario etc etc, and all that at ridiculous prices! :D
Failsafe is dead simple to program on the RX (set the controls like you want them for the fail safe, press a button... and done!)
I m waiting my 5dbi aerial for the TX, that should extend the range to 7+ miles (tested by a few guys on RCGroups :D ).... Don't need it, but will feel safer (peace of mind).
They are going to release a "box", like the Jeti box soon, with a few captors (vario etc)... Looking forward to that!
Anyway, you guessed it, I'm pleased with the system, cheap, secure, full of functions like bigger expensive brands (or even better for some...).
Next glider, the Alpina !
-
So, Mon Ami, you’ve entered the world of modern radio communication (2.4Ghz.) :clap:
Haven’t heard of ACCST. (Another type of channel hopping I presume) Each rx has to be linked to the tx, does it? At least you’ll have no fear of another flyer shooting down your precious Alpina.
I have to say I’m a little sceptical about telemetry. I can’t really see that it satisfies a need or offers an advantage to the pilot. :?: (Other than curiosity.)
I mean,………Dual Rates? Yes I can see the advantage of those.
Exponential?…….I can see the advantage of that as well.
Being able to mix control surface movements together?…………Yes.
All these things can, if the pilot wants to, be used to improve, or make easier the skill of flying. But Telemetry?
Don’t get me wrong, I’m not saying it’s a bad thing. But I just get the feeling that Telemetry is gimmick that the salesmen have come up with to try to convince us that it’s the latest ‘Must Have’ gadget.
What do you think of it Fred?
Keith
-
Hey Keith,
Yeah, that's like FASST, with diversity (the 2 aerials are active).
Never had a problem in 41 or 35Mhz, so that's a bit weird to me to move to something else knowing I never had any issues... But for the sake of safety, flying machines over 12 ~ 15Kgs, keep thinking that one less parameter to worry about (being shot down) might worth the hassle.
For the telemetry now, I think this is one more safe point to take on board. Knowing your battery voltage at all time in flight, is definitively a plus (even if I never had problems with batteries ! Part of the "job" to keep them healthty and check them before flying if you know what I mean).
Range... Well, that's default, so why not.
After that, I might get into a Vario thingy, but really don't feel the need, especially in Slope Soaring, that kind of remove the fun on thermal days! :D
So, to me, telemetry, yes, but not abusing it (voltage alarm, and that's pretty much it), I want to fly my plane, not spend my time playing video games!
And I never use Dual Rates :P
-
Hi Fred and All,
This 2.4GHz thing is interesting.
We all know (don't we?) that the 2.4GHz band was not intended for controlling models, but why not do it if it's possible?
There's lots of 2.4GHz activity around here. Even my broadband arrives by 2.4GHz link from Mt. Gabriel. That's about 9.4km away, but it needs special antennas both ends.
And the BB provider (Digital Forge) uses 2.4GHz for their back-links to connect to other of their base stations as well.
And of course nearly everyone has a home wireless network that uses 2.4GHz.
None of these used diversity as far as I know, as there are specific RF channels.
And having worked for a short while on frequency hopping systems for the UK MOD, they are surprisingly tolerant of interference.
You can still, of course, still suffer from saturation of a receiver input stages by a strong nearby TX signal, but that shouldn't be a problem when the RX is in a model aircraft.
But like you Fred, I have never suffered from any problems with 35MHz.
So should I change too? :?
Telemetry.
Now I can see a use for that.
Battery voltage definitely, especially if it could show minimum voltage during servo movement (highest current).
Vario?
Altimeter?
Well, full size glider pilots use them and they should be able to fly 'by the seat of their pants' unlike us poor earth-bound souls.
So yes, I would go for a vario and an altimeter.
And something that could be interesting is airspeed.
Where is the stall point?
When you are 'flying backwards' in a strong breeze, just how much slower can you go without falling out of the sky?
But first I have to just get the EG up in the air :oops:
-
Telemetry definitely has it's uses.
I just started using the Jeti system a short while ago. The standard functions on all the JETI 2.4GHz receivers are RX voltage and signal strength for each antenna. It's great to know the voltage of your RX battery and know you'll get a warning well before you ever fully discharge it. Don't know about the rest of you but I probably never drained an RX pack below 50% just in case (so all my packs were heavier than necessary or I got less flying time than I could have). I can see the signal strength function being useful too although I haven't made much use of it yet. For example it'll give you some warning if you're flying in a very "noisy" area where you wouldn't otherwise know there was a risk. It should be possible to use this as a lost model finder as well! :wink:
Probably the biggest advantage of telemetry for me will be measuring battery usage for electric planes. This needs a separate sensor so I won't be using it on my indoor planes for example but for larger stuff it's very useful to be able to monitor pack voltage, current draw and capacity used while in the air. Instead of timing the flight and guessing if you've used more or less throttle than usual you have a fuel gauge and you can put an alarm on it if you like.
So for example I put a current/voltage/capacity sensor in my electric glider. It's got an 800mAh pack in it powering the motor and radio. After flying a few climbs to altitude and some thermalling I wouldn't have much idea what was left in the cells so if I was to catch a thermal I'd be wondering if I had the power left to spend an hour circling in it. But now, with telemetry set to alarm after I've used 600mAh, I have absolutely nothing to worry about until the alarm goes off telling me I need to start thinking about coming down.
The telemetry doesn't get in the way of normal flying. The information is there if you need it but there's no need to even think about it the rest of the time.
Aidan
-
Hi Aidan,
I agree, the only thing, as usual that I see wrong in all those "aids", is the abuse of them.
In Retroplane, we sometimes see people flying gliders, in gale force winds and massive lifts... Using a vario... Come on! do you really need that?
Anyway, I'm a bad example, I don't use any mixage (just expo), flight phases etc.. I fly the glider, not the radio!
Mini pointless rant over :D
Just sometimes, I wonder how we managed to fly RC planes in the old days (here we go again...) without all these gizmos! :P Not that I'm against progress etc, but sometimes, just wondering. My first 4m glider, I only had a 4ch radio... Only servos reverse (that was a big thing to have at the time!).
And back to the subject, tested my 5Dbi antenna, and I can already see a great range improvement! Need to be tested on the field now, but even if that's useless, a few miles more range (7 miles in theory...) makes me feel a bit safer!
-
Now Fred, don't start me on 'the old times'.
What about single pulse 27MHz radio and escapement rudder only? :)
Ron
-
Ah 27mhz, that was fun ! :D Really had to learn how to fix your planes in those days! :D
Never had the rubber band servos! My first servos were the in-line ones.
Still remember my first "mini" servo... The size of today's big standard servo, but at the time, that was cutting edge technology! And not cheap!
-
ZZZZZzzzzzzzzzz....................OH! Have we stopped reminiscing now? :lol:
Actually this discussion has thrown up a couple of ideas that I hadn’t thought of.
I hadn’t paid much credit on being able to know a model’s rx/servo battery voltage in flight, having never had a problem with such things myself.
But then I’ve never had the “need” of a seat belt in my car, but I still wear one,……..Just in case.
Personally I wouldn’t have much use for varios’ or altimeters, but Aidan’s idea of the voltage reading of flight batteries would definately get a thumbs up from me. (For my powered planes) I can certainly see the benefit of that. :?:
(It’s always good to hear other peoples point of view.)
Keith
-
You're right Keith.
But.... I call them, or think of those times, as the 'bad old days'.
It's a bit like old cars.
We used to think they were great, but try driving one now and you'd soon enough jump back into your modern warm, dry, fully syncromesh, five geared, overhead cam, etc. etc. modern car.
So give me all the modern radio facilities that 'just work'.
Whether I actually need them or not is another matter. :?
I think maybe I do, but only if I don't have to pay more for them. :?:
(Well I did have a Scots Grandmother :wink: )
Ron
-
Quick update on the MC18.
So far so good with te 5Dbi antenna... I wonder why they don't sell these antenna with the 2.4ghz system by the way, as the range improvement is definitively here! :?:
Was also close to buy a patch antenna, like the Weatronic ones to put it flat against the radio case... Maybe some day...
By the way, another week to wait for the new Graupner 2.4 / telemetry system to be revealed! :D
-
Quick update on the MC18.
So far so good with te 5Dbi antenna... I wonder why they don't sell these antenna with the 2.4ghz system by the way, as the range improvement is definitively here! :?:
Probably so you buy the antenna as an extra! :o
K.
-
You might be right on that one! :evil:
2.4Ghz is a rip off in the model world I think...
This is "old" technology, easy to produce, cheap... :!:
-
CORRECT!! :x
-
By the way, Graupner announced their new 2.4ghz system (another one... :roll: )
Called HoTT (Hopping Telemetrie Transmission) based on a FHSS system.
Looks slightly inspired by the Jeti Duplex system :wink: and the "box" looks great !
4000m range is announced, ultra fast binding etc etc... And was supposed to be relatively cheap...
Checked the prices... I keep my FrSky for now :evil:
Sensors etc are cheap compared to others, but the 8ch receiver is 80 euros (ok, you have telemetrie...) but still very pricey to me...
Anyway, another system to keep an eye at, and hope hey do better than Weatronic and IFS !
-
Fred,
Any more updates on the reliability of the FrSky system? Or has the weather kept you off the hills?
-
Hi Bill,
So far so good, I just need to spend more time testing the 5db antenna now, but this is looking promising :D
Could not fault the system so far. But I keep trying!
Moved the system into my Alpina, but waiting for the weather to clear to fly it. Fingers crossed that will be all good with that one too! I might even put the receiver antenna at 90 degrees on that one! :lol:
Anyway, on forums, Frsky only have good reviews so far :D
Now, waiting for the full telemetry modules/sensor/box to be released!
By the way, if any of you are interrested in the FRSky stuff (modules, receivers, Futaba receivers etc), let me know, as we are now dealers for Ireland :D
-
Great news!
I'm planning to move to FrSky because of the possibility to develop on top of their telemetry system.
Just need to sell my Assan gear now. :(
-
Good news indeed!
And even more good news, and maybe a scoop, is that I'm working with FrSky for a few weeks now to have a telemetry module that fits the MC24/22/20/18 and also one that fits the MC3030/4000!
Hope to have a prototype soon, but that's good to have a manufacturer that is listening to their customers :clap:
Was fed up having to work out things with DIY modules, as you can only find plug and play stuff for Japanese style radios!
Another "scoop", they are going to release a module for Hitec radios soon!
So all good, and a very reactive company I must say! I'm just waiting on their "box" and sensors now :D
-
Any news if they'll have a "hack"module with telemetry?
I can pretty much go for the normal Futaba module but I'd prefer to have the hack module instead.
It provides a much cleaner install and I could have a 2-in-1 system with 35 and 2.4 but I definitely don't want to give up on the telemetry as that is 99% of the reason I'm changing brand.
(Next time I should go to FrSky first... they just released new hack modules with telemetry. :) Link: http://www.frsky-rc.com/ShowProducts.asp?id=76 )
-
Hey Nando, why haven’t I seen you up on the Big L. lately? :?: In fact, why haven't I haven’t seen you for years. :shock: At this rate you’ll be an old man with grey hair by the time we meet up again! :P
I noticed in that link you just mentioned that the DHT module operates on 6 - 13volts. I assume you’re not going to fly with a 4.8v battery!!
(Just thought I’d mention it, in case you’d overlooked that fact,….in one of your normal drunken modes!!! 8) )
Keith
-
Alright, scoop!
I have the photos of the new FRSky telemetry sensors etc!
Looking good! And great price too!
Seems that you need to buy a "module" where you plug the sensors into (receivers only have 2 ports for 2 sensors) but the module have... well, loads!
Sensors are temperature, GPS, Alti/Vario, fuel gauge etc, all options!
The LCD screen to read the info looks neat too!
Anyway, my pre-order is on the way, exited to test all that stuff!
Well, sometimes after.. the baby! (bombshell! O:) )
-
Ahhhgggg.
Not... THE BABY :twisted:
Congrats to all concerned. :lol:
But... more sleepless nights.
Worse than lambing season.
At least that only lasts a few weeks.
Ron
-
more time in the workshop and less time in the bedroom Fred!!
Congratulations :clap: :clap: :D :shock:
-
Congratulations :D :D :clap: :clap:
-
Thank you all :D
Should be with us before the week end I think!
-
BABIES :shock: More babies :shock: :shock:
Fred, how do you find the time? (let alone the energy,) to make babies! :?
Let me give you a piece of advise my friend,………….Invest in a television and a hot water bottle. (They’re a lot cheaper in the long run. :wink: )
However, on the basis that this advise has already come too late, Congratulations to you and your better half. :clap:
(Are you sure you’ll be at Retroplane this year???)
Keith
-
Hey Nando, why haven’t I seen you up on the Big L. lately? :?: In fact, why haven't I haven’t seen you for years. :shock: At this rate you’ll be an old man with grey hair by the time we meet up again! :P
I noticed in that link you just mentioned that the DHT module operates on 6 - 13volts. I assume you’re not going to fly with a 4.8v battery!!
(Just thought I’d mention it, in case you’d overlooked that fact,….in one of your normal drunken modes!!! 8) )
Keith
That's true Keith. :(
Problem is the Big L. is a bit far away I'm afraid so that's not too easy to go there often also with the holidays and so on I was a bit away from the island as well.
But I haven't stopped... :)
Actually I've been dealing with tons of RC projects, with a bit more of free time I'll share some here in the forum. But mostly is related to tricopters, quadrocopters and related software.
Yes I noticed that, but have in mind module is for the radio so there's no problem I'm already using in it a 3S 11.1v LiPo.
I only drink cider and I hardly see someone in drunk mode with cider... i think or maybe I'm already too dru... oh! never mind.
@Fred, when do you think you'll be sharing the prices on those?
I'm definitely interested as I'm almost sure I can combine some of the stuff I've been developing with the FrSky gear. :)
And congratulations! :clap:
-
Has the patter of tiny feet been heard in Dublin yet Fred?
Thinking of the Frsky set up, I fly my 3030 with the hand rests in place. Could the Frsky unit be hidden inside the rests?
(http://www.gliderireland.net/forum/images/uploads/billscottni/tx.jpg)