Moving to 2.4Ghz....

[Fred]

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 !  

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 !  

[Happy Days]

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  

K.

[Fred]

Hey Keith, thanks  

Getting there, slowly, but surely !

But I have to admit that it is hard to change a perfect working reliable system ! Must get old  

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 !

[IceWind]

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

[lothar4862]

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

[Fred]

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 !  

Hi Lothar   ,

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  

And without the big antenna, I now lean back when flying !  

[Fred]

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  

[Fred]

By the way...  :wink:

The box and content :



The 2.4ghz module... And where to solder the antenna  :!:  :!:



I used servo connectors at the other end.



The radio opened.. The 41mhz module on top :



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...



Et voila !



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.



Next stage, in flight !  

[Happy Days]

Very neat job Fred.

Question: How do you range check with the 2.4 module?

K.

[Fred]

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  

[Happy Days]

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.

[Fred]

No, no way of reducing the power. Not a surprise for a 20 euros module really  
I'll do the range check in Mt Leinster, at least, I'll know live, and in real situation !

[Fred]

Alright, here is a quick report about this cheapo 2.4ghz system : it works !  

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 !  

[IceWind]

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

[Happy Days]

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