Why do people get their individual achievements confused with a technical specification or what is a performance specification.I have gotten 2 mile range with my older single antenna Flysky.
Of late I have been looking into model crashes locally and found definite issues in maintaining signal even with the so called superior Spektrum radios. Just recently one local user landed his new high speed bird and complained that it appeared a little slow to respond at times. Upon inspection it was noted that he had 4 LOS occurrences in a 4 minute flight at a maximum distance of only 500metres. The light on a Spektrum Rx will flash once for each LOS experience it has from being powered up. (It is not how far it can work but rather the minimum distance at which it will always work)!
Definitely post your experiences but make them helpful towards reducing crashes or aircraft otherwise OUT OF CONTROL. Antenna setups and radios that caused issues or crashes should be posted so others can learn what not to do!
For instance the old favorite of interference, LOS issues experienced by DSM2 users at Flight Fest has been mentioned on the forum again this year and yet people continue to say how great DSM2 is! Even Spektrum has special warnings on the maximum number of DSM2 radios that can be operating at the same time in the same area and yet the warning and its reasons are not mentioned. People still use, (and recommend), DSM2 with its inherent weaknesses and problems!
Finally just a thought! Do not expect plane manufacturers or even radio manufacturers to take responsibility for a LOS induced crash! They make millions of dollars each year from us in replacement aircraft and aircraft parts due to poor quality radio communications. They will however improve their products IF we reject those products which are substandard or dangerous!
Have fun!
Sadly it is not Spektrum I have issue with but rather those who seem to gloss over the radio product issues and recommend the same old radios as being the best even though technology and product offerings improve over rather short time periods. I have observed blanket Spektrum recommendations being made without any clarification as to the limitations of their entry level products.Hai, I understand where you're coming from, but DSM2 and DSMX are two different situations. DSM2 uses 2 channels for spectrum hopping, switching back and forth, setting it on startup. DSMX uses the full 2.4 GHz spectrum. You're right, DSM2 is an inferior product. That's why DSMX was created. Is it perfect? No. Neither is FrSky. It has its own inherent frequency issues. So does FlySky, Futaba, etc.
I hate to say it, but this seems to be turning into a "bash Spektrum" post. I get it if you don't like them, that's fine - that's your prerogative. Let's give people clear, concise reasons to buy into a particular protocol. Otherwise, we're becoming more and more of a "Apple vs. Android" fanboy base. Each one has its pros and cons, and each one is going to defend their choice to the end. I just know that most of the issues lately that you've targeted as loss of signal can also be attributed to other failures, such as ESCs getting hot, motors frying, even guys who forget to replace the batteries for their servos in a gas powered plane (we had that happen as a loss of signal at our field - the owner of the plane hadn't replaced the battery pack for the servos with a fresh battery, and his gas powered plane circled up and out of sight, to be found a week later at a local rancher's farm).
I think maybe we all need to be a little more agnostic on which transmitter brands we like. It's ok to post why we like them (for example, I like Spektrum because of its ease of setup, I can hook up a Horizon Hobbies BNF plane quickly and simply, and the voice commands that it calls out are great, TO ME), but I feel like we're getting into bashing choices, and I really don't want FliteTest to turn into the seedy side of RCGroups.
If you want to talk about a new technology coming in the near future, great. Talk it up - give us the points why you should choose it. But maybe we can leave the trash talking to the politicians, wrestlers, and professional sports players.
Sadly it is not Spektrum I have issue with but rather those who seem to gloss over the radio product issues and recommend the same old radios as being the best even though technology and product offerings improve over rather short time periods. I have observed blanket Spektrum recommendations being made without any clarification as to the limitations of their entry level products.
I have Spektrum, FlySky, FrSky, and a number of other supposedly superior radio systems and EVERY radio system has its issues and sadly most are rubbish for fixed wing aircraft! I also have a number of retired radio systems including 36 MHz analog types. In the past I have also used Sanwa and Futuba. Lately I have been collecting, (through owner donations), a range of radios that are wholly unsuitable for fixed wing aircraft some of which have never been used and are still in their original packaging! Most are gifted by grateful students who realize that the first radio they purchased, (on hobby shop recommendation), is useless for their needs!
Currently manufacturers make a range of radios to suit individual applications and needs BUT then allow their products to be marketed as suitable for all applications even though basic theory shows that they are totally ill-suited to at least some applications. I really do not care what the label on the front of the box/controller says as to who is the manufacturer but rather the performance of the system. If the thread appears to be a little Spektrum heavy perhaps it reflects the popularity of Spektrum currently and the large number of users/devotees the brand has!
At my local club there are three main brands in use with Spektrum having the majority of users. The club also uses Spektrum and Flysky as teaching platforms! I recommend some Spektrum and FlySky products and warn against others based upon their radio operation in relation to likelihood of a LOS occurring!
Spektrum, FrSky, FlySky and almost every other radio manufacturer have, (some), product offerings which are not suitable for maintaining communication with a fixed wing aircraft and yet there is NO indication as to the limitations of their entry level products with the EXCEPTION of Spektrum which does have a warning of user number limitations in relation to the operation of DSM2. Radio communications performance or communication issues are almost totally ignored!
If someone is injured or killed by an aircraft due to a LOS incident using a radio setup that you personally recommended, would you accept responsibility for your recommendation? I do not know if I would want to and so I want to help persons make the absolute best decision for their own safety and the safety of others.
Those who read my posts would know that I am a club committee member, a flight instructor, a plane designer, builder, repairer and I even do radio repairs. My growth in the local chapter of this hobby took off when I started to actually improve my own radio equipment and installation quality. During my early days I crashed everything I managed to get into the air. I started this whole push in informing others of the radio limitations as a result of studying model crashes, (Mine initially and later those of other club members), and becoming a flight instructor as well as my current desire to replace my latest radio system with one that will last me the remainder of my life or close thereto.
So far I have been watching the latest Spektrum, Flysky, FrSky, Jumper, Sanwa and even Futuba offerings to try and ascertain which is best suited in technology, support, features, cost, and ease of use! To date there has been NO superior radio found though a couple have made the short list, including Spektrum. Unfortunately some are still repeating the same old radio issues/problems over and over!
This thread could end up being a Spektrum, Jumper or FlySky recommendation but the jury is still out at this time!
I am sorry if you have been offended by my raising an issue or two with SOME spektrum products but rest assured there is a common issue across almost every radio manufacturer's product range in that they do not give a product suitability rating and many products are actually substandard for fixed wing RC usage. Currently my personal recommendations are FlySky for entry level and Spektrum for high end radios but this is subject to change without notification as new products are released and further developments in radio tech become available!
Have fun!
Sadly that is not what I have said! I have said that almost every manufacturer makes some versions of their product that are unsuitable for reliable communication in fixed wing aircraft. The failing is that persons seem intent on associating their own preference for a radio brand as being suitable for every application. Some of almost every manufacturers product offerings are appropriate for terrestrial vehicles, (only), some for terrestrial vehicles and Quads, (only), and finally some for all applications including fixed wing aircraft! Sadly there is no apparent differentiation at the shop counter except the recommendations of the sales assistant or in our case the opinions and recommendations of fellow users! Spektrum radios are very good BUT not all Spektrum products are suitable for fixed wing aircraft!I think it's time I walk away from the FliteTest forums for a while. It sounds like anyone who likes a particular brand is being considered a danger to the hobby.
Sadly I wish my luck had been as good. On my return to the hobby it had all changed and my radio setup was suddenly considered as dangerous so I looked for a cheap radio system. Well I definitely got a cheap one even though it was recommended and many had claimed it had great performance for them. All it did for me was to create a huge pile of destroyed models. The radio always seemed to survive and it is still going strong though I do not use it any longer.Sadly, most LHS owners are entrepreneurs and don't do what they sell. Oddly most hobbyists are EXTREMELY cost concious to the point of being ridiculous. Generally not a winning combination particularly when one is just starting out.
As I have said before, I dont agree with many of his answers, but I have seen that @Hai-Lee knows his business, and you will always get a properly informed answer.
Back in the DARK AGES, when I was starting out, radio "glitches" were common and got to be the reason for so many crashes, deservedly or not. Due to the unique way some of my older stuff responds to LOS, I can say with reasonable confidence that in 30+ years I have had ONLY 3 or 4 LOS incidents. The remainder can be attributed to either being stoopid or flying too close to the edges of the sky.
My $0.02 YMMV
You are correct in all you say but it is not the maximum range you can achieve but rather the minimum range at which you can guarantee reliable communication that is what I am warning of.Virtually all radio problems can be traced back to improper antenna placement or antenna damage.
Foam and dry wood are essentially invisible to RF. Metal, carbon fiber, electronics and anything wet (trees with leaves, fog, rain) will block RF. If your put your active element right beside your carbon fiber spar, ESC or battery, you are asking for trouble. If your antenna lead is damaged you will kill your range. If you put a 90 degree bend in the active element, you will cut your range. Keep the active element of the antennas relative straight and away from things that block the signal.
All brands of the equipment we have today are capable of ranges far beyond what can be controlled by line of sight. All brands will fail if you don't install them correctly or if they become damaged.
The antenna repair has a story in itself. Apparently the owner had ripped the antenna lead off of his AS3X Rx which had a pigtail antenna soldered to a small board which in turn was connected via coax back the the main Rx housing. He had not asked for any repair as I may very well have been busy in a training session with my students.ABOVE last paragraph needs to be in BOLD font, possibly with flashing arrows and someone screaming on the street corner: "pay attention people!"
What part of "dodgy short antenna" did you make longer? I am guessing the coax portion not the active element so that you could position it better.
I did not bother to look too hard at the board but I did inspect the broken antenna wire before I replaced it, (to try and match the radiator material but it was little more that a piece of multi-strand tinned copper wire, (ordinary hook up wire)). I matched the diameter etc, to maintain the radiation resistance, (best as), but seriously I was a little surprised at the overall quality,So in essence you aquired a piece of Mil-C-17/(124) [my dash number could be off, been a while] and soldered it in place of the old?
By any chance do you know what type feed these are (gamma, delta, etc) or the impedance? They don't look like a Marconi, although theory says the air gap could be at either end which would make mounting simple and rugged. Could be a clipped dipole, come to think of it.
You are quite correct BUT a range test on the ground can only prove that at least one antenna is functioning and that you were in a position where the signal was not obstructed! Based upon that knowledge you can see that ideally a true radio range test should be rather elaborate and involve the range test being done a full 360 degrees around the plane as well as with the plane in all possible attitudes to the transmitter that the plane would achieve in flight, (The flight battery could be flat by the time such a comprehensive range test was accomplished)!Comments on LOS:
Why do pilots buy one radio brand and buy cheap knockoffs for their RX's? Remember the knock offs can't duplicate the orginal, so it's minus on the design(SO THAT THEY ARE NOT SUED). That will cause some los due to inability to match all conditions that were tested. Point being, buy the company's matching equipment.
Range tests: I doubt many pilots do not Range Check their airplane. Being a member of three clubs, I very seldom anybody go thru the paces of range checking befor they fly. Do you run the motor(s)/prop to see if no problems exist? How about after a crash? LOS is possible. If unsure, walk around the plane to see if los happens. When we pylon raced, we would walk around 360 degrees doing the range check with engine on so los isn't present.
Did you know the better radios have ways of using telemetry and meters hook to the rx to count fades,etc per flight.? In many cases, the problem is location of the rx and it's direction of antenna(s). Having a composite plane, it paid off for I got los range checking, I had the correct direction of antennas, but wrond distance from the motor. Change the distance of one of the satelite antennas to 36 inches away, problem went away. Check with your product support on how to set it up properly.
So, do a range check every so often to insure flying safety.