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Old Aug 19, 2009, 08:01 AM
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Concerning the low voltage issue:
http://www.rcgroups.com/forums/showt...66#post7753366

Spektrum does not only have little headroom, but it also synchronizes the servo outputs.
This means, that all servos begin to move at exactly the same time.
http://homepages.paradise.net.nz/bhabbott/Servo.html
This way, the current demand peaks of all servos are also synchronized. The resulting large current surge contributes to the problem.
Almost all other systems sequence the servo outputs, and spread the load over a time, insted of concentrating it.
The only other system despite spectrum synchronizing the servo output is XPS V3.
And, you might have guessed it, per default the manufacturer blames every malfunction on a "bad" RX battery, even when the very same setup has worked just fine before.
See a pattern here?

It is a myth that 2.4GHz systems all need more juice than MHz systems.
This has only been claimed by one or two manufacturers, whose systems really need more juice than the rest.
I for one consider it a valuable feature that my system of choice does not need a better power supply than usual.
First with Fasst, and now with Jeti, I can fly the RX packs I have used before, as they do not reboot above 2.9V.
In fact, I have even switched to using single LiIon cells on some light planes, and it works out great so far.
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Old Aug 19, 2009, 08:15 AM
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Russian Federation, Sakha, Yakutsk
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Quote:
Originally Posted by Julez
Concerning the low voltage issue:
http://www.rcgroups.com/forums/showt...66#post7753366

Spektrum does not only have little headroom, but it also synchronizes the servo outputs.
This means, that all servos begin to move at exactly the same time.
http://homepages.paradise.net.nz/bhabbott/Servo.html
This way, the current demand peaks of all servos are also synchronized. The resulting large current surge contributes to the problem.
Almost all other systems sequence the servo outputs, and spread the load over a time, insted of concentrating it.
The only other system despite spectrum synchronizing the servo output is XPS V3.
And, you might have guessed it, per default the manufacturer blames every malfunction on a "bad" RX battery, even when the very same setup has worked just fine before.
See a pattern here?

It is a myth that 2.4GHz systems all need more juice than MHz systems.
This has only been claimed by one or two manufacturers, whose systems really need more juice than the rest.
I for one consider it a valuable feature that my system of choice does not need a better power supply than usual.
First with Fasst, and now with Jeti, I can fly the RX packs I have used before, as they do not reboot above 2.9V.
In fact, I have even switched to using single LiIon cells on some light planes, and it works out great so far.
Amen Julez.
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Old Aug 19, 2009, 09:08 AM
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Quote:
Originally Posted by sebbe
My point is what pete also says: Spektrum is less tolerant of a bad setup than the competition.
I dont think everyone is so careful choosing the right setup, and many dont have the knowledge ...
How did you figure out that, quote "Spektrum is less tolerant of a bad setup than the competition" if you don't use any Spektrum equipment? Just by reading what others write?

It is fine that you want to know about many different systems and it is fine to have an opinion on other systems and state it. The problem is in the way you try to get it through to us.

With every system (as a system in general, not only 2.4GHz vs whatever MHz, not even only RC equipment) there are limitations which should be known and the system be used within these limitations.

Some Spektrum receivers have a limitation on power not to fall below 3.5V. Well, this is wa-a-a-a-y below the safe limit to fly. Although a servo will still work below 4V, how much torque do you think it will put out? I had to find this the hard way - by crashing a plane I loved to fly. Although the AR7000 receiver did not reboot (the LEDs on the main and remote receivers were solid on after the crash) I had control over the plane all the time but the control surfaces became very sluggish and the elevator servo could not overcome the airflow over the elevator while pulling out of a loop. In this particular case the battery was not adequate for the servos in the plane, not the Spektrum receiver.

Quote:
Originally Posted by sebbe
So all I really was trying to say is maybee other systems is better options for parkflyers wity linear bec and 3-4 servos...
If I already have a system to fly larger planes and gliders what are the other systems that really provide better options for, quote "parkflyers wity linear bec and 3-4 servos"? I use the 2.4GHz same system I have for electric planes with linear BECs and 3 to 4 servos without any issues. It is true that I had a couple of BEC failures but these were due to a bad ESC and one of these failures ended up in crashing the plane but it happened while I was still using 72MHz equipment. How would have "other systems" provided "better options" in this case?

Quote:
Originally Posted by sebbe
I havet not said spektrum is bad. every systems has plus and negative side, whats wrong with that.
Nothing's wrong with it if you do a fair and objective comparison with other systems, comparison that comes out of your own experience with these systems. Or you can point out the pros and cons of the systems you use and leave the discussion open for others to post their experience with the systems they use.

At the end forums are what they are - there's a lot of good info and a lot of hearsay. I read on one forum that the receiver of one of the cheap chinese 2.4GHz systems would not reconnect after a loss of signal unless the power to it is cycled (turned off and then back on). So, "What's up with 2.4GHz?"

Ivan
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Old Aug 19, 2009, 02:56 PM
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oh my holy crap ....

Well ok, spektrum DONT have any issues with low voltage, Like Ivan said its note safe in any way to go below 3.5 volts anyway, so spektrum is as good in this matter as for exampel Corona v2 that goes down to 2.25 volts..

OK, so:


* Futaba has no heat problem, because it is NOT safe to fly without any air in and air out that makes the fuselage colder, anyone just putting the receiver in a foamie without real airflow threw receiver is an idiot and shouldnt fly anyway

* Corona has no resolution problem that making your servos jerky, cause you wont really notice it in air

* Jeti didnt have lockoutproblems in begging of their relice, is was the costumer who didnt know how to put together a good setup that was suited for just Jeti, stupid costumer !!!!

* And of course Spektrum didnt ever had any low voltage problems, because the stupid poor bastard who have a little weaker powersupply should not fly, it works in some cases with Futaba fasst or Corona, but this doesent matter, if he had only a good reliable powersupply he wouldnt had this problem, And of course this is clearly stated in spektrum manual, and even a biginner should now this, or else he can stop flying..


Im done here, thanks for some interesting discussions...

2 things are for sure, 1') I maybe have a way putting words little bad and wrong, and 2) You CAN NOT say anything wrong about spektrum if you do not have 100% evidence and proof, you should also have a spektrum for your self, else SHUT UP !!!

Im shutting up !!!
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Old Aug 19, 2009, 05:21 PM
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Quote:
Originally Posted by sebbe
oh my holy crap ....

Well ok, spektrum DONT have any issues with low voltage, Like Ivan said its note safe in any way to go below 3.5 volts anyway, so spektrum is as good in this matter as for exampel Corona v2 that goes down to 2.25 volts..


* And of course Spektrum didnt ever had any low voltage problems, because the stupid poor bastard who have a little weaker powersupply should not fly, it works in some cases with Futaba fasst or Corona, but this doesent matter, if he had only a good reliable powersupply he wouldnt had this problem, And of course this is clearly stated in spektrum manual, and even a biginner should now this, or else he can stop flying..


Im done here, thanks for some interesting discussions...

2 things are for sure, 1') I maybe have a way putting words little bad and wrong, and 2) You CAN NOT say anything wrong about spektrum if you do not have 100% evidence and proof, you should also have a spektrum for your self, else SHUT UP !!!

Im shutting up !!!

Sebbe,

It's ok man. We understand.

One cannot say anything about the market leader (Spektrum/JR) without a legal case already built against them.

Point being: Other major companies (read - everyone else) can make things work in conditions that make Spektrum gear puke. However it's OUR fault for not running the gear properly...
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Old Aug 19, 2009, 05:40 PM
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Quote:
Originally Posted by FrogChief
Sebbe,

It's ok man. We understand.

One cannot say anything about the market leader (Spektrum/JR) without a legal case already built against them.

Point being: Other major companies (read - everyone else) can make things work in conditions that make Spektrum gear puke. However it's OUR fault for not running the gear properly...
Good post.
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Old Aug 19, 2009, 07:25 PM
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Quote:
Originally Posted by FrogChief
Sebbe,

It's ok man. We understand.

One cannot say anything about the market leader (Spektrum/JR) without a legal case already built against them.

Point being: Other major companies (read - everyone else) can make things work in conditions that make Spektrum gear puke. However it's OUR fault for not running the gear properly...

Good post.
Quote

Oh, give me an example.
Either you or sebbe or better yet each.

Sebbe hasn't even flown one!

You are an admitted 'Car Guy' . How accurate are your opinion(s)?
Color me very dubious.
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Old Aug 19, 2009, 08:10 PM
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Quote:
Originally Posted by onewasp

You are an admitted 'Car Guy' . How accurate are your opinion(s)?
Color me very dubious.
You must have some sort of tunnel vision or something because I did read all the threads and he did say he started using 2.4Ghz using Spektrum surface system, but he also said he flies. I don't know why you keep repeating the same thing even after he posted pics of him flying. Or do you believe a car guy cannot be a plane guy at the same time?

Adrian
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Old Aug 19, 2009, 08:29 PM
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Posts number 38 and number 55 in this thread:

Discussion - Yet another Spektrum Lockout - Plane Destroyed.

See for yourself.
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Old Aug 19, 2009, 08:41 PM
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Quote:
Originally Posted by onewasp
Posts number 38 and number 55 in this thread:

Discussion - Yet another Spektrum Lockout - Plane Destroyed.

See for yourself.
You must read postings how you want to read. My post above said I read all the threads, and that includes the thread you specified. Just to make things clear, I'll just say it. I DID read "Discussion - Yet another Spektrum Lockout - Plane Destroyed" thread.

You should go read it yourself again. Just to refresh your memory, Frogchief did say he used Spektrum 2.4 surface system, but the reason he mentioned his car experience is to tell you that he had more experience with 2.4Ghz systems than you since surface system was available before the air system. And after him being labeled as a car guy by you, he stated he flies gliders and posted pictures. What's the point of calling him a car guy even AFTER he said that? Are you so bent on discrediting him and just cannot see he flies too?

Adrian
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Old Aug 19, 2009, 08:56 PM
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This is his reply:

:44 PM Report This Post to a Moderator #53
FrogChief
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Quote:
Originally Posted by onewasp
Which translates as "opinion only".

How does a "Car Guy" become an authority regarding the full range air performance levels of Spektrum?
Your experience has been surface, not full range air and yes there IS a difference.
Quote

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Yet they still release products far too often, which strongly suggests rushed product. It certainly does in the PC component world.

I never claimed to be an authority. I simply presented my critical opinion and the reasons for it.
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Old Aug 19, 2009, 09:09 PM
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Quote:
Originally Posted by onewasp
Yet they still release products far too often, which strongly suggests rushed product. It certainly does in the PC component world.

I never claimed to be an authority. I simply presented my critical opinion and the reasons for it.
I already read that as I stated above, but thanks anyways.

So where does it say he doesn't fly and only drives cars? I must be blind. I cut off your posting to just display Frogchief's reply. The part that says about him being a "Car Guy" is what you posted.
Adrian
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Old Aug 19, 2009, 09:59 PM
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I have tested over 20 Spektrum/JR Rxes. From AR6100s to R921s. The all worked down around 3 volts. The actual range was 2.93 - 3.03 volts.
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Old Aug 19, 2009, 11:41 PM
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Quote:
Originally Posted by onewasp
This is his reply:

:44 PM Report This Post to a Moderator #53
FrogChief
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Quote:
Originally Posted by onewasp
Which translates as "opinion only".

How does a "Car Guy" become an authority regarding the full range air performance levels of Spektrum?
Your experience has been surface, not full range air and yes there IS a difference.
Quote

Reply
Yet they still release products far too often, which strongly suggests rushed product. It certainly does in the PC component world.

I never claimed to be an authority. I simply presented my critical opinion and the reasons for it.

Your critical opinion is garbage.

I've been around the block a few times.
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Old Aug 19, 2009, 11:59 PM
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Quote:
Originally Posted by codezilla
You must have some sort of tunnel vision or something because I did read all the threads and he did say he started using 2.4Ghz using Spektrum surface system, but he also said he flies. I don't know why you keep repeating the same thing even after he posted pics of him flying. Or do you believe a car guy cannot be a plane guy at the same time?

Adrian
Good post Adrian:



Seems he'll latch onto anything that confirms his views...

Doesn't matter that us sailplane guys regularly range out further than most and need 110% performance from our gear. We're HARD on our gear and find weakness very quickly.

One good reason why Spektrum released the 'carbon fuselage' AR6250 Rx, because they were caught with their pants down.

Release after release after release after release. All to address shortcomings in product line that was rushed into production to maintain market leader status.

Bind & Fly? Another 'reason' to choose Horizon product. Just disposable trash that makes a killing on margin.

Watch JR defect and Horizon / Spectrum spin the news any way possible to keep customers calm...

JR has developed a Freq-hopping 2.4 protocol and WILL go that way; just watch. Sure they'll say it's for a 'foreign market' or some other damage control BS but it'll happen.

Why?!?!

Because Spektrum air DSS was always a half-baked product that was not ready for primetime.

At least thats the way some see it...
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