Model Boat Mayhem
Technical, Techniques, Hints, and Tips => Radio Equipment => Topic started by: phillnjack on December 28, 2010, 02:59:08 pm
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I have a very good 35mhz field force 7 futaba radio tx and rx.
Can this set be converted to the new 2.4 ghz stuff or is it not an option ?
Im not exactly electrical minded, but having a good radio has always been what i want.
this might be a silly question, but if it can be done, then what sort of price to convert it ?
phill
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Yes.More than one supplier lists your radio. As being able to be up graded.E Bay under areoplanes lists Fsky.Corona As selling suitable
units. Item 280607320672 lists a fsky conversion at £26.99.Uk seller.Has listedhis phone number. Im sure a call to him will answer
your questions.Giant cod also do 2.4 conversions. John
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thanks for the info
it realy would be nice to use this legally.
i like the set as its got plenty of stuff to allow for servo rate changes etc etc.
Plus its just a nice set all round.
phill
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Although it isn't listed in FrSkys compatibility list there are several people on the internet using the FrSky V8FT module in a Futaba FF7 successfully. I'm using it in my Hitec Eclipse 7.
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Im not sure what you mean to use it legaly.Unless the unit comes with a ce sticker and the importer has the appropiate certificate
from Ofcom. Then to use may not be within the law. If you buy direct from China then you are the importer. Having said this it
appears no one bothers anyway.Your insurance may not be valid. as equipements not as brought. The MPBA appear to be doing an
excellent job of sitting on the fence ,stating it would take a group of lawyers to decide on this matter.The answer remains as clear
as mud. Of which ive been up to my waders in. John
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When i say legaly, i mean use 2.4ghz and not 35mhz on a boat.
Im not supposed to use 35mhz for boat stuff but i often do.
If im going to run a boat out at sea, i use my 35mhz tx and rx, due to the reliability of the set.
and the fact that nobody else is around.
Thats what i mean by legal etc.
Im not worried about ce marks etc, thats all just a big big con.
phill
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there are several conversion kits on the market , does your radio have a modual for the frequency ? this i belive to be a straight forward plug in swap . i was also bebating converting a 40 mhz hitec set but seeing the latest offering from planet ive just bought the new planet twister 2.4 ghz 6 channel computer radio with 8 model memory which retails at £70 for both a transmitter and receiver !
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Futaba do one as well for it.
http://www.stevewebb.co.uk/index.php?pid=FUTPFTM07&area=Radio
http://media.radiocontrolzone.com/mair/RadiosPage/articles/article2.pdf
most shops have the receivers
Peter
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Have a look at this.
hope it is of some help
http://www.giantcod.co.uk/frsky-24ghz-futaba-combo-module-receiver-p-404882.html
kind regards
Alan
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Sorry Phill, there is
no excuse whatsoever
for running a toy boat on the the toy AIRCRAFT Freq. What recourse would someone flying using 40 moggies have in the event of an "Event"?? >>:-(
If im going to run a boat out at sea, i use my 35mhz tx and rx, due to the reliability of the set.
and the fact that nobody else is around.
You can obviously see both behind and a 40" span exocet at 1/2 to 3/4 of a mile away?
Regards Ian.
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it would appear circlip that some modellers dont care what frequency they operate on ! i started when it was just 27mhz , and regular interference from cb radios , now that you can buy a good multi chanel 2.4 set for less than a 27 or 40 mhz 2 chanel set !
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Well circlip
when do you come across rc airplanes 3 to 4 miles out at sea ?
and i have no concern at all with rc plain fliers when they use 27am/fm or 40meg, and many of them still do.
I have used 35 meg on helicoptors and had no problems with my set.
i do have plans to have the set put on 2.4 if i can cheaply.
now where do i buy a good mulit channel 2.4 set thats cheaper than a 2 channel 27 meg set ?[/b]
phill
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Errr, 27 moggies AM/FM Is legal tender for ALL forms of model? Still use a Quantum and a Sanwa on my toy
plains planes.
For plane fliers to use 40 moggies is also inexcusable, no, - - - - - - g STUPID
Regards Ian.
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now where do i buy a good mulit channel 2.4 set thats cheaper than a 2 channel 27 meg set?
http://www.giantcod.co.uk/gianitcod-24ghz-4channel-mode2-transmitter-p-403779.html
for the tx/rx (4 channel)
http://www.giantcod.co.uk/frsky-v8ft-24ghz-futaba-module-only-version-p-405313.html
reads like a conversion for several futaba tx's, yours might be in the list.
CE labelling is a really good idea when things go pear shaped and you need to be able to prove a point legally in order to keep your house. Litigation is an expensive business for those who make up their own rules.
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Has anyone ever been sued by another modeler,ever made a claim against insurance for a crash,(boat against boat; plane dropping out of the sky because of interference etc) or even claimed on their own insurance for damage while sailing?
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Naff all to do about claiming from another modeller Frankie, 2 fatalities from someone being hit by model Gliders. SMAE brought in the minimum nose/spinner radius rule because of this.
It's bad enough with the crossover of Legal frequency usage without some dopey p - - t doing it with disregard illegally.
"But it's only - - - -"
Yea, right.
Regards Ian.
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If your referring to me being dopey , do yourself a favour and keep your opinions to yourself.
you have no idea as to where and when i operate my models.
as i have stated , i will be probably be changing to 2.4, but i also operate on other frequency.
Now that £25 radio set would never be seen in any of my boats.
No way would i send out a 50mph boat using toy radio.
please dont anyone try telling me that this stuff works as good as even the cheapest of the futaba 27am stuff.
The range claim is terrible, i need more range than toy stuff, might be ok for slow electric or sail or steam.
But no way good enough for large fast boats travelling at speed.
Ive seen people bragging about this crap reaching a whopping 3oo meters !!!! thats not range, thats just a blip.
If 2.4 is only short range then ill stick to 27am, i get a long way with that.
phill
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you must operate your models through feild glasses then ? ive been using a planet t5 for the past year with absolutly no problems , even better for your application as its got a built in fail safe !
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This all seems to be far too good to be true to be honest, im a bit old school, you get what you pay for etc.
A few more questions about the 2.4 stuff
How do you go about losing control in waves etc.
What i mean is, say im on the beach, boat is say 3 to 400yards out waves around 1 foot giving a 2 ft swell
will i then lose control using 2.4ghz.
I dont lose it on 27am at the moment, ive heard rumours about it not being much good for water stuff.
I know subs are no good with it but im hoping to never have my boat going down.
Is this purely line of sight type radio ? like ship to shore vhf radio ?
It just all seems far too good to be any good for the price.
I realy dont fancy using cheap nasty finnished plastic tx that looks like its from the poundshop.
I know that many people are using the stuff, but are they using 5 foot long powerboats doing 50mph plus ?
if i buy a module and rx from say giant cod, am i getting the same performance as a futaba module or is there a real big difference.
i might seam to be comming across a bit harsh, but i realy dont want any high speed mishaps.
sorry to those who i might of offended in this topic (unless your a flier, i hate fliers, they have far too much enjoyment from their hobby)
phill
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Well circlip
when do you come across rc airplanes 3 to 4 miles out at sea ?
What i mean is, say im on the beach, boat is say 3 to 400yards out waves around 1 foot giving a 2 ft swell
The thot plickens. %%
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Ok circlip it seems your out to be pedantic.
Ill write this slow just for you..
most of the time if i have been using 35 with rc boats ,would of been doing so offshore,
roughly 3 to 5 miles out at sea from a full size boat platform.............only planes out there are normaly full size !
The question about from a beach was a totaly different scenario, ( something different)i.e from a beach situation where i would normally use 27 am.
And yes i do also operate from the beach, but like everyone else i am restricted for speed untill 300 meters out. (By laws )
now if i am standing on the beach, and lose sight of model for a split second due to wave height ( water waves, not me waving my hands),
am i going to loose control using 2.4 ?
(http://i1183.photobucket.com/albums/x479/phillnjack4/model%20boats/modelatsea.jpg)
now was that slow enough for you circlip
phill.......(http://i1183.photobucket.com/albums/x479/phillnjack4/icons/7_3_109.gif)
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I use 35Mhz when there is no one around
I dont lose it on 27 Mhz
Why use 35Mhz?
Just do as you like and paint the rest of us as idiotic
Just the sort of person that could bring licensing in again
On the beach someone could be flying an aircraft
You have 360 deg vision
Pillock
Sorry mispelt the handle <*< <*< <*<
Ned
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Y e s, b u t I ' m n o t s t u p i d e n o u g h t o u s e 3 5 m o g g i e s f o r t o y B o a t s
:-))
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Location ..........Mouth of the humber...suits you very well
there is no law that says i cannot operate any model on 35meg when 3 miles out
go check the laws on this before accusing people of doing something illegal.
youl also find you can legally use 27am cb radios out there as well, like many foreign boats do.
phill
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Some fought long and hard in the 60s/70s for Clean frequencies to be able to operate our toys with as much safety as could be shown to an ignorant population some of whom regarded it their RIGHT to operate illegal radio communications. The mechanism was there that if one wanted to talk to others, a test had to be passed to ensure that they understood the basics of what they were doing.
Sadly, the "B - - - - r You" brigade stamped all over legislation and even when allocated a correct system (27FM) many of the CB wallies wouldn't change the illegal equipment they'd already bought, some even advocated going to the local model shop and getting a transmitter crystal to substitute cos "You can get a load MORE channels out of the "Rig" that others can't get".
The first allocation of a specific frequency for use by Aircraft modellers only was 35Mhz FM. This was mainly due to the fact that toys working in THREE dimensions (ferget Subs) were more likely to cause injury (Serious) than a toy boat hitting a bank to anything other than the model. Clever thinking by the regulatory board, they also informed a moaning boat brigade that they too would have an allocation at a future point, so DON'T use 35 for boats.
Good to note stupidity, still seems to be regarded as a virtue. Probably don't need to prove ones capability to drive a car then? You really should be careful when playing at sea, It's quite legal for a seven year old to drive a full sized power craft, HE don't need to be insured EITHER.
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Phillnjack
You came on the forum asking for some information that was supplied by members
That is what we are here for.
We also try to abide by the rules
35 MHz is reserved for Fliers
If a flier on the same freq caused you to lose a boat
you would not be a happy bunny
I know someone who flies a large aircraft controlling it from his dads cessna
Hope he doesn't fly over your bit of the ocean
Ned
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I give up with you two, you obviously cant read , or wouldnt come out with such crap
phill
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Phil&Jack,
For arguments sake, let's assume that most all R/C transmitters have an output power of somewhere around 100 millwatts. Let's also assume that it's pretty safe to say that, in reality, most all R/C transmitters have an output power of far less (some can be as little 50mW or even lower). Making sense so far? Now, bear in mind that the characteristics of the 2.4GHz frequency is waaay different from that of, say, 27MHz or even 40MHz -- even though they may indeed have the amount of power outputs. 2.4GHz, being Ultra-high frequency is, as you rightly said, mostly line-of-sight. UHF does not penetrate or travel across water anywhere near as good as a HF signal would. For the record, 35mHz and 40MHz is just inside the VHF part of the radio spectrum, whereas 27MHz is near the upper edges of the HF spectrum. In other words, a 27MHz signal will radiate across water slightly better than than a radio operating on VHF and UHF frequencies.
In case you're wondering, the reason for all this gobbledegook is to try to answer your question of whether you will lose control of your model when it's hidden by a two-foot swell. If you are using UHF, then I would hazard a guess of "yes".... especially over a distance of several hundred feet away. Aircraft models, on the other hand, are a different kettle of fish. Being that the R/C receiver in a plane is much higher above ground level means that the UHF signal will carry a far greater didtance. If you were operating a model plane then I'd have no hesitation in recommending one of those 2.4GHz units from, say, GiantCod. But being that you are using a model boat - and under such extreme circumstances - then it might be best if you were to stay with 27MHz.
For what it's worth, there are some excellent 27MHz R/C transmitters available dirt cheap nowadays. And if you wanted to be really naughty, you could easily beef-up the output power in order to make sure that your little 100mW signal has a far greater chance of making sure that your model stays under control... even if it does hit a two-foot swell.
My only other word of advice would be to avoid 27MHz Acoms sets like the plague.
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Thanks PMK you have answered my question.
as for the acoms, its funny you say that as ive never had a problem with acoms , but never used acoms apart from a lake.
Ive used an old jr beat radio on 27 am no probem on rivers and at sea, but only on flattish water.
I think ill stick with 27 am for a touch longer, and just keep my ff7 on the back burner for a while.
what do most of the offshore racers in omra use ?
phill
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On second thoughts I'm not sure that I have answered your question.
As you know already, the FF7 is a superb radio - not to mention the excellent spectral purity of the output signal. Like JR, some of the more modern Futaba equipment is built for quality - and the main RF output board is housed inside a separate plug-in unit. So, to answer your initial question, yes - the FF7 can be converted to 2.4GHz quite easily. Very cheaply, too. Myself and at least one other Mayhem member have converted a Futaba 9C (which is just a beefed-up version of the FF7) for 2.4GHz. The new 2.4GHz board employs a similar channel-hopping system as that of Futaba - and the appropriate receivers are miles cheaper, to boot.
I didn't mean to bad-mouth Acoms equipment, but I've lost count of the number of Acoms sets which have quite a dirty output signal. i.e: nowhere near as tight nor as clean as the JR or Fut' gear.
Regarding 27MHz transmitters, you might want to consider one that uses frequency modulation (FM, as opposed to AM) - preferably one which uses a receiver with dual conversion and not single conversion... if that helps any.
Sorry I can't help with the OMRA question.
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i think you will find that ALL OMRA modellers will be using the legally allocated frequency ! 35 mhz has always been , and always will be specifically for AIRCRAFT USE ONLY model cars and boats work very well using 27 or 40 mhz to which we have been allocated , just because you choose to operate upto a couple of miles off shore dosnt excuse the fact you are operating on an illegal frequency ! the other members arent talking "rubbish " merly stating the facts i cant see any problems using a 2.4 ghz set in a 2 foot swell , ive a metre class yacht that spends quite alot of its time either on its side or with its bow under the surface of the waves , ive been doing this for best part of a year and had no problems with control .
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Phill,
As a bystander, pretty good commentary (and I see your point), :-)) :-)) even though you may not like/agree with some of the answers. O0 O0
At the end of the day the choice is yours as you don't have too heed any advice (all extremely good, knowlegable and experienced) given. <:( <:(
Bottom line is, if you break the rules, doesn't matter which ones and it goes pear shape then be prepared to pay the penalty. :police: :police:
There is thread on the forum, about a plug in FrSky module, for converting Futaba to 2.4 also Giant cod has a Video review (favourable) of the conversion.
Some one locally,(from where you are as you have not indicated a location) might be able to provide the links. :-) :-)
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"...ive a metre class yacht that spends quite alot of its time either on its side or with its bow under the surface of the waves , ive been doing this for best part of a year and had no problems with control ."
@ triumphjon:
That's comforting to know. But, just out of curiosity, are you sailing your yacht on a lake/pond, or briny sea water? And what distance is your yacht from your transmitter when its bow is under the water?
Pardon me if these Q's sound a tad cheesy, but believe it or not, these parameters (especially salty sea water) will have a certain effect upon the transmitted signal reaching the receiver in the model. If you are indeed sailing in sea water with 2.4GHz, then are you able to achieve glitch-free control over the same sort of distances as those used by Phillnjack?
Again, apologies if this sounds in any way cheesy. I'm just curious is all.
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Thanks pmk, greatly apreciated info.............
Triumphjon, Now being as you have a sailing boat that cannot in any way whatsoever be compared to a powerboat
apart from they both float, radio glitches of even half a second would probably not be noticed by you.
But a boat travelling at say 50mph having a 1/2 second glitch could of veered ofcourse dramatically.
3 foot sail boat possibly 4 knots if its realy quick one, 5 foot powerboat 45 to 50 knots if a quick one.
im not knocking sailing boats, they look great on ponds, and lakes.
I personally have not seen many rc sailing boats on the sea, ive seen a couple in a sheltered harbour though.
they probably look pretty good on the salt water waves.
But you state you have had no problems with 2.4ghz even with a bow under water,
where on your sail boat is the reciever, and how high is the ariel ?
phill
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my receiver is mounted inside of a baloon and about half of an inch below the deck , when operating the deck is no more than 1 1/2 inches above the water , the areil on the receiver is just over an inch in length ! as for the speed of my sail boat i feel this to be irrelevent , and as the radio has its own built in fail safe should any problems arise the radio will activate the chanel as set by the owner of the set , which can be set to whichever chanel you require and can be set to do whatever you would like the fail safe to do ! the fact that i used to race both in ic multi and off shore events , and often now operate my electric models in the solent .
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reciever ariel is only half an inch long ? are all 2.4 meg reciever ariels only half an inch long ?
Is there any benefit in making a longer ariel to protrude outside of the hull ?
I normally have ariels that resemble scale vhf or around 1 foot in height, but if they dont need
then even better i suppose..
But half an inch, that does surprise me.
I too used to dabble with multi's a long time ago, the days of mini jaguars ,jumbo jaguars, opus 40's etc.
when the wee mccreggor radio was considered good stuff,futab only came metal cased, flexi shafts were new ideas,
and the thought of ever getting new 2 channel radio for only £50 was considered mental.
Digimac 2 was the cheapest at £79.50 = 2 weeks wages.
phill
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Hi phillnjack
have a look at this pic ,it is the 2.4 set up i have in the surfury
hope this helps
aye
john e
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Frequency and ideal aerial length are closely related. At low frequencies such as 27MHz, a few centimetres either way on what is probably a piece of wire set to about 1/16th the resonant length doesn't make a huge difference, not really enough to notice. However, the odd millimetre out on something tuned to 100,000 times the frequency is going to be critical, and will probably prevent reception by effectively tuning the entire thing out of band. Real digital signals are tremendously robust - they can produce a good result even after a great deal of mangling, but when they go beyond limits, they GO. Very suddenly.
The big advantage of the lower frequencies in your situation is that you can fit a longer aerial, and you can mount it vertically. This way, there is less likelihood of it being hidden behind a wave enough to lose the signal. Bear in mind that signal strength does drop with range, and a partially hidden aerial will be less effective than one in full view. Also my previous comment about digital systems - none of the pre-2.4 systems are fully digital, they are analogue transmission systems that use the RX to create a digital signal. The RX can take a weak, possibly badly distorted, signal and produce a viable digital signal to work the servo, right up to the time when the limit is exceeded. Sensitivity will probably improve - selectivity will suffer (open the window further, more flies come in) but in your situation, this should not be a problem.
Most model boating happens at less than 400 yards range - we like to see the boat. On most venues the transmitter will be a good few feet above the water surface (and the bank usually doesn't go up and down by itself), so the very short aerials associated with 2.4, although very near the water level, are very rarely obscured. Many have two aerials, and take a vote on which is working, with a bias to doing something, which accounts for them continuing to work even in quite lumpy conditions. A long swell on open sea will be very different, not least because your boat will at some time be in a trough at the same time as the model.
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Hi all, I have bided my time to see if anyone has picked up yet on the 2 photographs and about interference on 2.4s (blind spots if you want to call them that) . When I first tested the Surfury out on 2.4 I had a problem with the planet 5; when I switched the set on - it would swap modes. It was originally set up throttle on left hand stick and rudder on right hand stick. This would just happen for no reason at all - instantly swap over - pretty dangerous.
The other thing, when I had the Surfury in the pool in the garage, if I lay the transmitter on the ground whilst I was adjusting the motor, even though the transmitter was only feet away from the model, it would lose signal. I am not sure if this is just 'one of those things' but, until I get it sorted, I myself have been reluctant to run this model on an open lake - you see gone are the days for me when I could run after a model if it goes astray - so I am considering going back to 40 mghz.
Just some food for thought there.
I know there are a lot of off shore lads use 2.4 and swear by it, but, I have yet to be fully convinced.
aye
johne
bluebird
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the better sets have built in Failsafe, also has the aerial been painted, and could you not get any more of it it in to free space so it has a chance to work ?
HS93
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Interesting thread, and the type I swore not to get involved in... However, rather than using an illegal frequency set on a model boat, and painting all boat modellers as irresponsible, why not spend a little bit of cash on a 40mhz set of similar spec, power boating isnt a cheap side of the hobby, why be a cheap skate about it and use an aircraft set to operate yuor model??
We run models with pyrotechnic effects fitted so can stand on our own soapbox about how the lesser modellers "wouldn't understand". We don't though..
Suggest running a couple of extra miles off shore into international waters or better still a bit closer to France, I'm not sure but they may use the 35mhz frequency for all sorts of nefarious RC activity!!!! :-)
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as ive been told the ariel on the receiver is actually a small coax type wire , therfore lengthening it isnt possible ! however ive been using a planet t5 set since last march and havent experienced any problems with range or loss of signal , its pssible to change the sets from mode 1 to mode 2 as there is a selection switch inside the back of the set , there is also the fail safe switches inside the set . considering this set costd just £50 i consider it well worth the money ! having considered the idea earlier in the year about converting a hitec tx that i had , somebody offered me a good deal on it so ive bought another planet 2.4 transmitter , the new 6 chanel with 8 model memory for £55 minus the rx !
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Having been using the futaba 2.4 system for 18mnths and have NEVER had an issue with range with a 1mtr yacht,sailing with the deck awash reciever on the blind side,in other words 2ins down in the hull and under water at ranges in excess of 400 yds,yes I know it's a tiny speck,never failed to resonse.had trouble in the past with both 40 and 27hz even though areal was above water .Strange but true
stavros
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funny that stavros , the comment i had earlier was that due to the fact i had a yacht in similar conditions its not as quick as a nitro powered race boat ! i dont think speed is of the issue , more the fact that WE still have control of our models !
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well im suprised the sail boats do so well with their decks underwater ?
The sub boys who have wanted 2.4 have been very dissapointed and told it dont work.
The makers of the radios say it dont work,
The people who sell the radios say it dont work.
Yet here we have sailing boats that have had their recievers deliberatley placed below waterline getting
fantastic results even when the decks of the boats have been covered by water !!!
Maybe everyone is lying about how bad the water is against 2.4 i dont realy know, i aint got 2.4ghz.
but id do understand the difference of losing control at certain speeds.
A fast model powerboat can be travelling at 90 feet per second by the way.
a rc sail boat travels at around 6 feet per second.
phill
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well im suprised the sail boats do so well with their decks underwater ?
The sub boys who have wanted 2.4 have been very dissapointed and told it dont work.
The makers of the radios say it dont work,
The people who sell the radios say it dont work.
Yet here we have sailing boats that have had their recievers deliberatley placed below waterline getting
fantastic results even when the decks of the boats have been covered by water !!!
Maybe everyone is lying about how bad the water is against 2.4 i dont realy know, i aint got 2.4ghz.
but id do understand the difference of losing control at certain speeds.
A fast model powerboat can be travelling at 90 feet per second by the way.
a rc sail boat travels at around 6 feet per second.
phill
Phil,
I also don't have 2.4Ghz plus I don't think we are on the same boat.
What I am understanding that is being said is, that decks awash, not submerged, can be handled by 2.4Ghz. Perhaps because there is only a momentary loss/disrution of signal if any.
Whereas submerged, that is a submarine which is under the water the 2.4Ghz signal is degraded, particularly in salt water.
So as not to labour the point if you do a search of the forum relating to 2.4Ghz it will bring all this to the fore. O0 O0 O0
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The offshore chaps seem to have no problems racing in OMRA a properly installed 2.4 is normally no problem in big waves, it is used extensively in the UK and USA in big boats that run in rough water.
HS93
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i too cannot see a problem in a swell , the radio waves must be bouncing over the waves ? im told the frequency is the same as used by our moblie phones , which still work when we travel up or down hills or behind buildings , having bought now my second 2.4 ghz radio ive not experienced any issues with its signal or range , and i doubt that many of us can see to the point of the radio being beyond its operating range anyhow ?
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i too cannot see a problem in a swell , the radio waves must be bouncing over the waves ? im told the frequency is the same as used by our moblie phones , which still work when we travel up or down hills or behind buildings , having bought now my second 2.4 ghz radio ive not experienced any issues with its signal or range , and i doubt that many of us can see to the point of the radio being beyond its operating range anyhow ?
The radio waves bounce off surfaces. The only way they can go from the sea surface is up, and having bounced, carry on upwards. Cellphones work in most places because there are a great many transmitters, and the cell phone picks from a selection the one it likes best, and has the ability to change on the fly. There are still dead spots even so. In model use, there is just the one transmitter. The scenario here is not extreme range, but a transmitter going up and down because the boat that the operator is on is going up and down, as is the boat under control. There will come a time when both are is a trough at the same time with possibly a lot of sea and several waves in between. Wave swells tend to have a gentle slope, and reflect. Steep waves will absorb, and after going more than a few inches into the water, the signal will have all but vanished. This is the same problem as the submarines have. The model could have its aerial out of communication for long enough to give trouble. A temporary loss of power would not be a problem (assuming a fail safe) but a loss of steering could be.
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Thankyou malcolmfrary .
you have explained it perfectly.
Now ill just use 27am for a while , and maybe get 2.4 for when i want lakes and rivers.
and i think ill get my futaba converted to 2.4 then i know i have a good set, rather than cheapo.
If the cheap ones are that good i cannot see why futaba and likes havnt gone bust yet,like mccreggor did when
futaba made cheaper sets.
Thanks everyone for all your input on this subject, im now off to look at prices for conversion stuff on tinterweb.
happy new year to you all
phill :-))
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This is of course a personal view but i agree that Futuba radio gear is overpriced.Its manufacter is now in Taiwan. Quality is still good.
But the price is ott. The chinese makers are getting better all the time.Why did i buy Futuba? Well at the time there was only
Spectrum and Futuba.If i brought now id buy Radiolink. Cheap and cheerful but does job.This is 2.4 that im talking about. John.
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Ive been looking at futaba modules and others sold by the likes of giant cod etc.
I cant believe how much the futaba stuff is , over priced is an understatement.
if the giant cod stuff is as good for conversions then i think ill be getting one from them or places like them.
anyone got any good cheap sites for conversion bits and pieces ?
and is it realy as simple as pull out the module, chuick a new one in and its ready to use ?
phill
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from the information ive read , if your radio transmits through a modual its a simple unplug and plug in a new modual ! as the hitec radio i had didnt have a modual it was going to involve desoldering and resoldering which i wasnt to sure about , but as the new planet twister radio was so well priced , and ive already got a planet t5 ive bought a purpose built set . although i enjoyed the ic offshore racing my budget doesnt allow for buying the fuel let alone rebuilding engines when they let go , hence i now use elecy models instead .
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Hi there Phillnjack
I purchased the 2.4 ghz module from Giant Cod and it really is just a case of plug the module in. Far superior in reliability than a Planet T5 radio set-up.
Pic attached - I think I paid about £30 all in - for the module and receiver.
aye
john
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Hey, my man -- given that you have zillions of models, all you need now is one of these...
http://www.spartan-rc.com/products/ultrapac/ultrapac.php
...sourced from here...
http://www.modelhelicopters.co.uk/cgi-bin/sh000001.pl?REFPAGE=http%3a%2f%2fwww%2emodelhelicopters%2eco%2euk%2facatalog%2fNewItems_NewItems%2ehtml&WD=campac&PN=RadioAccs_Spartan%2ehtml%23aSRC00512#aSRC00512
<edit>
And don't forget that it lets you delve into the Service Menus, from whence you can twiddle and tweak your radio to your heart's content.
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My idea of tweaking up a radio is to recharge the batteries %%
everytime ive tried to do something involving repairs, ive ended up buying more again.
if its mechanical ill fix it, if its electrical ill kill it.
plug in sounds good to me.
from what ive seen im thinking about the giant cod site frsky v8 module and reciever thingy
p.s
ic engines dont go bang and wear out easy if you keep the nitro down and stick to around 4/5ths power.
all the flat out merchants obviously wont agree, but ive watched many of the lower powered engines beat the top
engines due to over doing it.
I do not include SC engines in the above statement though.
phill
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Hi this is the 2.4 ghz module from Giant Cod that i used :-))
http://www.giantcod.co.uk/frsky-24ghz-futaba-combo-module-receiver-p-405262.html
aye
john e
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Phill&Jack, hold on a minute, because, after re-reading what I'd told you previously regarding a plug-in module for your FF7, I think I might have inadvertantly fed you the wrong information. I brought my FF7 back from the States (working on 72MHz), and if your radio's internal circuitry is similar then I'm afraid that you cannot simply plug a 2.4GHz module in there. Apologies for any misunderstanding, but I was confusing the FF7 with my 9C.
If you're up to it, remove the rear cover, take a peek inside and see if it resembles anything like the one in the attached photo. If it is, then it does indeed mean that you cannot use the plug-in modules. However, all is not lost, but it means that you'll have to resort to a spot of minor surgery. I suggest that you point your browser here... http://www.giantcod.co.uk/frsky-24ghz-conversion-hack-module-p-405206.html
The so-called 'hack' unit means that you'll need to solder just three wires, but it's not that difficult to do. On my particular FF7, since 72MHz is illegal here, I opted to remove most of the original RF components and then utilised the remaining free space on the 72MHz board in which to locate the 2.4GHz unit. I also removed the original telescopic antenna and then stuck the smaller 2.4GHz antenna in its place. It's actually easier to do than it sounds. Those three wires I mentioned on the hack unit; two of them are the supply wires (positive and negative) and the third wire carries the signal pulse from the FF7's on-board encoder circuitry. All these connections can be made from the square 'trainer' socket on the original RF board. As you know, there are six pins on the trainer socket, but me, I was able to trace the appropriate pins with an oscilloscope. Otherwise the relevant pin-out information can be gleaned with a simple Google search.
You say that you're not too hot with electrics, but don't worry because there are loads of members here who are handy with a soldering iron. Just ask and I'll bet somebody will offer to do the modification for you.
Good luck.
By the by...
Now't wrong with SC engines. I've been using SC 4-strokes on airframes for some time - no problem at all. Dead easy to start and sounds beautiful when idling.
I guess that now makes us equal after my whinging about Acoms equipment. ok2
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Mine dont look anything like your one inside
on the front mine say FP-T7UPS pcm/ppm selectable pcm 1024
here is a few pics of what mine is inside and out including module
(http://i1183.photobucket.com/albums/x479/phillnjack4/model%20boats/tran3.jpg)
.
(http://i1183.photobucket.com/albums/x479/phillnjack4/model%20boats/tran2.jpg)
.
(http://i1183.photobucket.com/albums/x479/phillnjack4/model%20boats/tran1.jpg)
.
(http://i1183.photobucket.com/albums/x479/phillnjack4/model%20boats/tran4.jpg)
phill
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Ah, in that case, I stand corrected (when you said FF7 I thought you meant the 7-CAP).
Even before I reached the fourth photo I could instantly tell from photos #2 and #3 that your radio will indeed work just fine with a plug-in module after all (the small PCB at the top-centre with five pins gave a tell-tale clue). The GiantCod version has the 2.4GHz antenna integral to the module itself (some don't), which means that you don't have to drill any extra holes in your radio to install the antenna, nor do you need to do any soldering.
For the price, the performance and transmitted range of the FRSKY unit is quite amazing - and the 8-channel receivers are dirt cheap. Why spend the best part of £70 for a 7-channel Futaba receiver?
Bear in mind that for the GiantCod module to work correctly you need to make sure that your Tx is set to transmit in PPM mode - not PCM mode.
Enjoy!
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Thanks for info
by the way what is the difference between ppm and pcm mode ?? i have no idea what thats all about.
infact this radio has a lot of stuff that i have no idea about or forgotten about ha ha .
when i get a new module, i think ill make a nice little guard around the ariel from it
phill
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PPM = Pulse Position Modulation.
PCM = Pulse Coded Modulation.
All transmitters emit a signal at a given frequency. Let's assume 27MHz. The signal itself (otherwise called the carrier frequency) is simply being sent at a frequency of twenty-seven million times each second, but doesn't do much else because it carries no information. This 'information' thingy can consist of anything such as voice signals, or, in this case, encoded pulse signals that the R/C receiver can hear, and then converts (decodes) the information from the carrier frequency to a pulse that the servo can understand.
In the case of PPM, the pulse signal for each servo channel can be on for as little as one millisecond (servo horn at its left extreme position) or on for as long as two milliseconds (servo horn at its right extreme position). From this you will be able to deduce that a pulse length of 1.5 milliseconds will put the servo position at its neutral (centre) position). The PPM signal is then repeated over and over again - usually around twenty times each second. Your servos are being updated with the relevant information of its position 20 times per-second (or 50Hz), in essence giving the effect of the servo arm moving quite smoothly whenever you move, say, your rudder or throttle gimbals. Also, the PPM information is sent sequentially, meaning that channel #1 position is sent first, then channel #2 position, then channel #3... and so on. If, say, you want to alter the position of the servo on channel #3, the PPM signal first sends the information for channels 1 and 2 before reaching channel 3. This happens so fast that as soon as you move the gimbal which controls channel 3, it appears to happen almost instantaneously.
Clever stuff.
PCM, on the other hand, works in a slightly different way. The PCM signal is superimposed on the carrier frequency in the usual way, but instead of the pulses being sent sequentially, they are now 'sampled', meaning that they are sent in the form of a digital representation of the usual PPM (analogue) pulses. The buzz word is 'resolution'. The higher the resolution, the better the quality of the transmitted pulse signal. It's all to with 'bits' and 'bytes'. In your case the PCM resolution is set to 1024 bits. You can do all sorts of clever things with the digital signal, such as to tell the R/C receiver to ignore bad burst of data, or operate failsafes, etc, etc.
Me, I personally prefer to stay with the PPM (analogue mode) for reasons I shan't bore you with here.
Incidentally, I wonder if you can turn on and off, say, a light switch at exactly 20 times each second, and hold it on for a duration of exactly 1 millisecond (one-thousandth of a second), then repeat the process over and over. Then try doing the same at 27 millions times each second. And did you know that 1GHz is the same as one thousand million times per second? You'd need a pretty slick wrist action to operate the light switch at that rate, huh? Around these parts, that aforementioned wrist action is otherwise known as the 'vinegar stroke'. And being that this is family forum, it's best that I don't go into detail about it.
Are you beginning to wish that you never asked now?
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Are you beginning to wish that you never asked now?
YES
Ha ha
thanks for info
phill
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PPM = Pulse Position Modulation.
PCM = Pulse Coded Modulation.
All transmitters emit a signal at a given frequency. Let's assume 27MHz. The signal itself (otherwise called the carrier frequency) is simply being sent at a frequency of twenty-seven million times each second, but doesn't do much else because it carries no information. This 'information' thingy can consist of anything such as voice signals, or, in this case, encoded pulse signals that the R/C receiver can hear, and then converts (decodes) the information from the carrier frequency to a pulse that the servo can understand.
In the case of PPM, the pulse signal for each servo channel can be on for as little as one millisecond (servo horn at its left extreme position) or on for as long as two milliseconds (servo horn at its right extreme position). From this you will be able to deduce that a pulse length of 1.5 milliseconds will put the servo position at its neutral (centre) position). The PPM signal is then repeated over and over again - usually around twenty times each second. Your servos are being updated with the relevant information of its position 20 times per-second (or 50Hz), in essence giving the effect of the servo arm moving quite smoothly whenever you move, say, your rudder or throttle gimbals. Also, the PPM information is sent sequentially, meaning that channel #1 position is sent first, then channel #2 position, then channel #3... and so on. If, say, you want to alter the position of the servo on channel #3, the PPM signal first sends the information for channels 1 and 2 before reaching channel 3. This happens so fast that as soon as you move the gimbal which controls channel 3, it appears to happen almost instantaneously.
Clever stuff.
PCM, on the other hand, works in a slightly different way. The PCM signal is superimposed on the carrier frequency in the usual way, but instead of the pulses being sent sequentially, they are now 'sampled', meaning that they are sent in the form of a digital representation of the usual PPM (analogue) pulses. The buzz word is 'resolution'. The higher the resolution, the better the quality of the transmitted pulse signal. It's all to with 'bits' and 'bytes'. In your case the PCM resolution is set to 1024 bits. You can do all sorts of clever things with the digital signal, such as to tell the R/C receiver to ignore bad burst of data, or operate failsafes, etc, etc.
Me, I personally prefer to stay with the PPM (analogue mode) for reasons I shan't bore you with here.
Incidentally, I wonder if you can turn on and off, say, a light switch at exactly 20 times each second, and hold it on for a duration of exactly 1 millisecond (one-thousandth of a second), then repeat the process over and over. Then try doing the same at 27 millions times each second. And did you know that 1GHz is the same as one thousand million times per second? You'd need a pretty slick wrist action to operate the light switch at that rate, huh? Around these parts, that aforementioned wrist action is otherwise known as the 'vinegar stroke'. And being that this is family forum, it's best that I don't go into detail about it.
Are you beginning to wish that you never asked now?
PMK,
Informative and educational as usual.
Thank you O0 O0 O0 :-)) :-)) :-))
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Very very minor quibble - the "20 times per second" should really be "repeated at 20 millisecond intervals" to get 50Hz.
At the end of the frame of information (after the last channel) you get a quiet bit, longer than 2mS, which the receiver recognises as the reset to start looking for the 1st channel. With 27MHz systems, which are pretty universally PPM and AM as well, interference turning up in the quiet bit can be interpreted as channel 1 information, and since channel 1 is commonly the rudder, this is why the first sign of interference is the rudder twitching. FM sets work differently, and are more immune to that kind of interference, but are very rare in 27MHz. Readily available in 40MHz, but generally costs more, so mostly found on the more comprehensive outfits with lots of channels and magic bits.
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Man, you sure have a keen eye! And better at explaing things than this bozo.
Regarding the attached photo, and the "quiet bit" that you mentioned, I guess I should have set the timebase to 2mS/cm in order to clearly see reset period between channel 7 and the next sync pulse in the overall 20mS frame.
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Ahhh, but what if the gizmo shows that the wotsit aint doing what it should be ?
does this then mean that the thingymebob wont allow any whatdoyacallits to operate at the right time.
Or is it ok as long as ive got a fully bent crankenshafter saddlewobble holder in my other hand ?
phill :-))
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Sounds like you have got the' handle' on this one!!
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yep, i just need a very big hammer and a mig welder and im ready to do radio mods
phill