GliderIreland - Ireland RC Forum - Flying Model forum in Ireland
Gliders => Slope Soaring => Topic started by: Ron on April 06, 2008, 12:46:57 PM
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Hi again all,
Sorry I've not been around the forum, or anywhere else, for quite a while.
Family illness problems involving a lot of shuttling between here and the UK. Now looking a lot better.
This year I have a big 'old wooden boat' job to do, and have decided to keep her ashore for the summer to stand a chance of getting everything shipshape by next year.
Only boaty fanatics would understand that, I know.
So now the time has come to re-assess the model flying situation, and what it boils down to is - start again.
And by that I mean new sailplanes, and new radio too.
And that's where I need advice from all you guys.
Now I've been around radio comms nearly all my life (ex radio 'ham', and worked in digital/packet radio since it was invented), so the new 2.4GHz systems look interesting. Except - they work on a public radio band.
Yes I know frequency hopping and digital pairing takes care of a lot of problems. But we fly from the tops of hills, often near relatively high-powered transmitters, and all 'built-down-to-a-price' equipment is deficient in the RF department, especially when it comes to excluding unwanted signals, even out-of-band ones.
Then there's the vastly different 'line-of-sight' characteristics from the frequencies that we normally use, not to mention the higher absorbsion rate of heather clad humps that always get in the way!
So - what are your opinions of 2.4GHz as applicable to sloping?
Anyone used it yet?
And on radios in general, whether 2.4GHz or 37MHz, is there a transmitter that can be set up by plugging it into a laptop via USB maybe?
It would make it a lot easier for setting rates and couplings etc. than ploughing through all those menus on a tiny LCD screen.
And.... (do go on a bit don't I. Sorry) for a 37MHz radio, is there a decent synthasized one, and not just the transmitter.
Carting loads of crystals about is a pain, and when you have some single conversion RXs and some double conversion it gets even more confusing.
Your opinions would be very welcome.
What do you use and what do you think of it?
If you were changing, what would you go for?
Happy landings. :D
Ron
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Interesting info here:
http://www.multiplex-rc.de/cms/vorschau/upload/sonstiges/2_4_GB.pdf
So think I'll leave the 2.4 GHz stuff.
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Oops.
Typo...
Of course I meant 35MHz not 37 :(
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Hi Ron
Good to "hear" from you again! Sorry about your family illness, it must be a very trying time for you.
I have no experience of 2.GHz, so I'm not qualified to answer. From my own perpsective, however, I am not ready to move over, as I remain unconvinced that it is fully tried and tested under all conditions. I do know there are "issues" with aerial placement within all-carbon fuses, but maybe that isnt going to worry you too much right now :roll: !
One of the big advantages of 2.4 is the freedom to fly when there are a lot of fellow flyers around, there's no waiting for your frequency peg to come free, etc. Obviously that is not a major concern for me, I'm more concerned with finding someone to fly with now and again!
Obviously radio choice is a personal thing, and people are likely to recommend what they use themselves. Still I'm going to stick my neck out and say that I sincerely don't believe there is a set close to the MPX Cockpit SX right now that will give you such a range of features for a very reasonable price. Features include full synth mode (compatable with synth or crystal receivers), channel check, "no rf transmission" programming mode, aileron and flap off-set to allow increased movement of those surfaces by off-setting the servo arms, automatic suppression of aileron differential when engaging spoilers, etc. etc. They are particularly powerful sets for gliders, and very easy and intuitive to programme for a hopeless "non-nerd" like me. Limitations are 7 channels, and 20 model memory.
I have bought a MPX EVO9 with the idea of replacing the SX, for four reasons only: more model memories; more channels (for when/if I get big scale models one day); the ability to assign any function to any control and channel (servo); which means that you can often use a smaller Rx than what you need for sets with fixed channel assignments; and the ability to change settings whilst in flight (for instance, adjust elevator compensation for spoiler braking mode). It is possible to leave one setting or mixer open for in-flight adjustment with the SX, the evo however allows you to open and close two parameters in flight.
I don't think the SX can be set up on your PC, although sofware patches are expected to be introduced and can be downloaded and installed via your pc. I have a computer cable for the evo, which I have used to upgrade and reset the set to factory settings (I bought it 2nd hand), but again I dont know if you can set up a model via the pc (that doesnt mean it can't be done).
TBH the programming of the evo has eluded me completely to date, if I don't get it sorted soon I'll probably sell it again and get a second SX!
My tuppence worth :roll: !
Cheers
Chris
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Hi Ron, sorry to hear about your family illness :( Hope all is going to go well now !
Well, you have an answer from Chris...
But you will have as many opinions as you have modelers ! :D
Quick thing regarding the 2.4Ghz... Multiplex is at a wait and see state (well, there friend from ACT took the wagon before them... Long story, but seems that pi** them off a little :P :wink: ) as we are waiting for a new European legislation about our use of the 2.4Ghz... So far, not confirmed, but our use of the 2.4ghz is certainly going to be restricted at best... Wait and see !
But the 800mhz technoligy is around also..
For me, I keep my good old system, flying far from me often, and the risk of losing the signal is real in these conditions...
Anyway, as a radio, a cockpit is a good choice... You also have the Graupner MC/MX 12 in this kind of range.
Personnaly, I have a MC18, never had a problem, very reliable, and now running on lipos (I haven't charged it for 3 months now ! :D :D ). I also have a Royal EVO9 synthese (great with synthese receivers ! Just find a free channel, and off you go !) but I don't use it much.. (going to change...)
All that to say, that the day I find a MPX 3030, I'll go for it ! Certainly one of the best radio of all time ! :D :D
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Hi Chris and Fred,
Thanks for the ideas.
Yes I guess there are as many radios as there are modelers. Well nearly.
Funnily enough, I had been gradually steering towards the Cockpit, and then the evo9.
I like the idea of assigning any control to any function and any channel.
As to 2.4GHz, nope. Not for me.
Apart from the undecided European regs, there are too many potential problems.
I get my broadband via a radio link from Mt.Gabriel, about 9k away as the RF flies.
And it used to be on 2.4Gig.
However, there were so many interference problems, despite the highly directional antenna, that the guys had to change it to 5.3GHz.
Been fine ever since.
Hey Fred!
What's all this 'Sold Out' on EasyGliders.
I was going for one of those to get me away from X-Plane and into the air :(
Cheers All,
Ron
PS. When's the next 'fly-in'?
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Hi Ron,
Part of the new EU legislation, is because of this, the 2.4ghz is now almost saturated ! You can switch between 200 frequencies, but if the 200 frequencies are already taken, back to square 1 !
But poor modelers like us are the least of there problems !
Beside this, technically, I'm far from going 2.4ghz ! Might be fine for planes and helis, but us, gliders, we fly sometimes out of sight, and sometimes, beind obstacles (like landing out of sight down the slope, beind tree lines...) and I like keeping the control ! :P
For the Easygliders, very popular !
Back in stock soon, with some very good news on the Multiplex front ! :D :D
We can put one aside for you when they are back if you want :D
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OOppss, missed one question !
Next Fly-in is the 20th, in Cork :D
After that, that's the ISR fly-in, the 10 and 11th of May at Mt Leinster with Europeans pilots :D
Details are here : http://www.gliderireland.net/isrmay08.htm
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Hi Fred,
Yes please. If you could put an EasyGlider aside for me that would be good. Just the glider, not going for electric, just as long as it's got spoilers/flaps.
Where is the Cork meet?
It would be good to make it to the Mt.Leinster fly-in too. You never know, I might just have something to actually fly by then :o
Is there anywhere to stay in that area, just in case I can make both days?
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Hi Ron,
No problem, we'll keep an easyglider for you.
But the easyglider don't have flpas.. just ailerons :?: Is that ok ?
Otherwise, we have the club easyglider that you can use, I'll bring it during the fly-in just in case !
For the Cork Glide-in, the meeting is at Noel Barrett's Shop on Washington street at 9am (if I'm right... :?: )
For the ISR Fly-in, I'll let you know where we are staying with the lads coming from abroad, more than happy if you can join us ! (I'll stay for the night too...I can predict an headache the next morning ! :wink: :P )
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Thanks Fred.
Oops, my mistake. :( Must be thinking of something else (as usual!) with flaps.
Yep that's fine.
Might be able to do a bit of mixing and get flaperons. Hmmm....
I know Noel Barrett's shop so no problem there.
I'll look forward to the headache.
Well.... perhaps not :lol:
Now... I must write a note to the weather man...
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Ron, the EasyGlider brakes really well using the aileron "up" mode (spoilerons?).
Perhaps we might consider sharing some of the ride to Mt. Leinster?
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Hi Chris,
That's good. Spoilers make it sink faster which is usually what I need, and it feels better than flaps where you have to point the nose down and head for the earth :lol:
Yes good idea for the Leinster trip.
Presumably you'd be staying overnight too.
We could meet somewhere.
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Hi lads. I agree with Chris. I have the older version of the Multiplex Cockpit and its very good. Its also very light. I beleve that the newer version, the cockpit SX, has even more functions. Thats my 2 cents :D .
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Hi,
about using 2.4Ghz for some time i tought in giving it a try. I have a FF9 so i would only have to buy the transmitter module.
Thing is i've been following this and there is still many reports of problems, also the saturation of the band as stated before is also a issue.
Also when everyone was happy about the 2.4Ghz some company comes up saying that the 900Mhz is the best option... so my opinion is that is still to early to go for it. The features i think they are great and the advantages, but until everyone gathers and chooses a wide band available and less prone to problems the market will still see many changes.
In the mean time the best option is to go for a radio that at least has a separate transmitter module!. :)
About editing the configurations in the PC the closest thing i've seen was some guy making and developing a software to interface the Futaba CAMPAC modules and edit them using a PC. But the interface code is not shared by Futaba so de develpment on this is slow.
Oh about the cristals, at least for futaba you can get the synthetized TX module and the RX's also.
I wanted to go for that but i haven't had much fee time (€€'s).
Choose well and have good flying times! :)
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Just a quick question. Synthetized means you can choose your frequency without using crystals right. Would a Multiplex synthetized Tx work with a hitec ( or other manufacturer) synthetized Rx. Or would you have to have a synthetized Rx from the same manufacturer as your TX.
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Hi Alan, no need to be the same brand...
For instance, I'm using my JR with synthese corona receivers, and i do the same with my mpx evo9 with the corona synthese receivers...
No glitches what so ever !
:D
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Thanks for all the info chaps.
Alan: There seems to be a Cockpit MM now.
http://www.multiplexusa.com/product_fs.htm
But I'm still leaning towards the Evo 9.
Icewind: (Fernando - is that right?) Yes the 2.4 is out for me.
They used to say don't buy anything until it's at least up to version 2, and 2.4GHz is still at version 0.5 in many ways :lol:
And a synth TX module is a must.
As to the editing on a PC... If, and this is a big IF, I have absolutely nothing to do at all next winter, I might just look at writing something to do it.
After all, it says it saves a file of some sort to the PC, so it should be possible to read that file, modify it with a user friendly interface, and save it back again.
Hmmmm... Perhaps :wink:
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Yep.
Synthesized is just the way the basic RF frequency is generated.
You either use a fixed device like a crystal, or you have an integrated circuit that also uses a crystal, but an internal one, and it generates whatever frequency you want according to switch positions or software settings.
The result is the same as far as the rest of the transmitter is concerned.
8)
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Just an add-on I thought of...
You don't even have to use a synth TX and synth RX together.
You could have a synth TX and a crystal RX, just as long as they are both on the same channel. :D
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Thanks for the info Fred and Ron.
About the coctpit MM. I'm sure some shops may still have it but I think its out of production. The cockpit SX has replaced it.
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Thanks for the info Fred and Ron.
About the coctpit MM. I'm sure some shops may still have it but I think its out of production. The cockpit SX has replaced it.
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Opps double post :D
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Hi Alan,
Yes most shops seem to have the SX. It's only the Multiplex US web site that has the MM.
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Yes Ron it's Fernando. I may have to ask the admins here to change my nick! :) Everyone uses their name so should i.
Regarding the editing of the configs i think that is highly possible. If the file scheme was know it would be possible to edit it.
There is some work being done here: http://ourworld.compuserve.com/homepages/wallacelouie/cms.htm
Well regarding using only a synthesized part in one side, i don't see much use for that. Because the main advantage i'd take from it is to easily change channels. If i'm using cristals in one end i'd have to own the cristals for the different freq in the same way.
Unless and this is my question, are the synthesized modules and RX's modules more accurate? In what concerns filtering and not being so prone to parasite interference from nearby channels or other sources?
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Hi Fernando,
Yes editing the config files is worth a look, if and when I get the urge :)
All I was thinking was, having a synth TX you could still use older crystal RXs that you might have laying around. That's if you haven't changed over completely yet.
As to stability and frequency accuracy, I would say the synth ones are better.
Crystals vary a lot from one to another.
What they tend to do in production is make a load of crystals and then pick out ones that are within limits for each channel. And sometimes the limits can be rather wide. After all, they have no reason to make the limits narrow as that just means they are throwing away more.
And sometimes the temperature characteristics of crystals is not good either.
As to filtering and interference rejection, naturally the better the frequency accuracy the better matched the TX and RX frequency are going to be, so there will be less tendency to pick up adjacent channels etc.
But generally, what determines the interference rejection is good, preferably double tuned RF stages, good I.F. (Intermediate Frequency) filtering with crystal filters, and double conversion helps a lot giving two opportunities for I.F. filtering, and other techie stuff to do with image response.
Hope that helps :lol:
I like the look of the Corona RXs. Good spec.
Ron
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Hey Ron,
Leaving the boat in the shed for the season is one thing, but ditching your brown sails icon is too much :( Sailing boats are just gliders on water :P , with variable aerofoils, that sink instead of crashing.
Good luck with the flying, me at the same crack, have a mountain just crying out for a glider. War bird on the way.
Seán :D
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HiYa Sean,
Wish it was in a shed. It's in a boatyard (costing an arm and a leg) with a big cover over it.
Sorry, her!
And there's jobs like pulling a keel bolt to check it's still in one piece after 48 years :(
Yes perhaps you're right.
The new one is supposed to be a Seaking over the - errr - sea.
But really it's just a shot from X-Plane simulator.
Original icon coming up.
What's the war bird?
Ron
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The Cockpit SX is, I think, a considerably more powerful tranny than the older MM, and, given its very reasonable price for a Tx, I wouldnt recommend trying to sniff out an old MM.
Ron is right in that many of us have perfectly serviceable crystal recievers lying around, and you wouldn't want to ditch them. Having a synth Tx just gives you more options, thats all.
I have used my synth SX with the following crystal Rx's with no problem(let's see now :?: ): Hitec electron 6, Jeti something-or -other, various 7 and 9 channel MPX ppm rx's, Schulze Alpha 8's, Futaba 6 and 4ch, Corona's. The only synth Rx's I've used is the Simprop Scan 7, also works great. I suspect Corona's are the best news we've had for a long time :D .
Fernando: you can go into your user profile and add in extra stuff such as your name (such as with my profile), without changing your username. You could also just sign off with your name :roll: !
Chris
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Yes I think it's got to be a Cockpit SX.
Good TX and a very reasonable price.
All I have to do now is find one :?:
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I got mine from Germany out... Much better priced than the UK. I'll post a link..
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Ron,
The war bird is from Island of course! A 1.2 m Me 109???? Coming very soon. Watching your thread to decide on radio! Keep you posted.
Seán
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There you go: Cockpit SX tranny only for EUR 159: http://shop.lindinger.at/product_info.php?cPath=1286_1288&products_id=61653. Shipping will be EUR 15. I buy a lot from Lindinger.
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Seán: Have to keep my head down then if there's an ME109 about :lol:
Chris: That's a very good price. About €175 then. Hmmm. :?:
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Wow that is a good price. I might get one myself.