Spektrum debuts Quick Connect to address voltage drop concerns

[Ashley Davis]

so why these new RX's then?

Let's say the BEC has a momentary hicup and drops below 3.5V (not Spektrums fault, dodgy BEC).....how long would you like to wait, personally the faster the better. Spektrum are improving the product, that is all. Now we have instantaneous reconnection instead of 0.5 seconds (ish).

[ChrisB]

Agreed,its just ongoing development like some heli manufacturers do,and which is appreciated

[Stuart]

Ash,

It maywell not be a design fault of the Specktrum system as it was obviously designed this way. However, nothing was mentioned or is mentioned unless you reall look for it with regards to voltage issues on the RX and possible re-boot or lockouts.

Horizon Uk site for the DX7 mentions zip, the adverts mention zip, the retailer sites mention zip. The DX7 manual only mentions it on page 102 and again this is rather strange as it gives a voltage of 4.7v as a minimum. Now the system is sold giving the impression that a normal 4.8v system is okay with servo's rated @ 4.8v or 6v and I can't remember if a batt was in the kit but if it was the only ones I have here other than my existing lipo's are 4.8v.

For me its not too much of a concern as the only heli that uses the 2.4ghz is the camera ship with a FP reg system on it and its hardly thrashing the sky's. Whilst all the others are on 35mhz G3 systems and will be staying this way.

My personal opinion is that Specktrum released a system that seemed on the face of it to be the answer to alot of frustrations with the growing electric market and frequency issues. However, they neglected to inform customers of key saftey issues using this system before making a purchase.

Regardless if it was designed this way or not, to NOT inform or raise this point openly or mention it within any promotional material in the details specifications of the system is for me poor trading practices. It maywell breach trading standards for electronic goods and I suspect it wasn't raised as they knew it was a weakness in the system. Now that's it's raised its head high enough only now are they overcoming the issue.

So I believe they have a moral and potentially legal obligation to put right all system sold regardless.

[Tim Procter]

So I believe they have a moral and potentially legal obligation to put right all system sold regardless.

Amen to that..

[Bikeracer]

here and its incorrect

And i read that Spektrum rejected the channel hopping idea early on,patented their system so Futaba are left with the dregs..

Just read this on Spektrums website.....

There are two main broadcast methods that spread spectrum manufacturers can utilize. One format is called Frequency Hopping Spread Spectrum (FHSS). With an FHSS system, the transmitter transmits a narrow band signal and rapidly jumps from one frequency to the next, spending a few milliseconds on each frequency. Originally, Spektrum engineers started their development with FHSS-based systems because they were relatively easy and inexpensive to develop. However, they soon discovered that FHSS had several limitations that would prevent it from being the optimal solution for RC. While more difficult and costly to develop, our engineers began experimenting with Direct Sequence Spread Spectrum (DSSS) and optimized the modulation scheme to overcome critical response and re-link issues. DSSS systems transmit on a single selected frequency but on a very wide band. Only a small portion of that band is used for specially encoded information. In addition, DSSS offers an increase of processing gain for significant improvements in range. With years of development and testing, the DSSS modulation scheme was optimized for RC car and airplane use, and Spektrum´s DSM 2.4GHz Spread Spectrum Technology was born. DSSS provided engineers and hobbyists with the safety, security, and locked-in feeling that is necessary to maintain total and complete control in any vehicle or aircraft.

..............

And here is the link to their site with more info

http://www.spektrumrc.com/DSM/Technology.aspx#whyDsss

Well they're hardly likely to say the Futaba system is better are they.

It's immaterial to me anyway,I don't care who makes what so long as it works.I'm only using three channel stuff so what I've experienced will probably not apply to helis.

All I do know is my Futaba set works with the same battery and servo set up that the Spektrum fails on.The Futaba system also drains a lot less out of the battery as regards the amount required to recharge them and this can only be down to the receiver in use.

Allan

[Smoothound]

I use a Spektrum car system in a JR R1 Tx on 2 cars and it's never missed a beat. It's not a gen 2 car system either it's the old original system and it works fine on a Nitro Buggy and an electric 16th Buggy. Go figure...

[moyesboy]

Regarding the receiver current drain.
I just powered my raptor up via the wattsup. I have separated the reg/servo supply from the rx supply.
with all the servos and gyro running and system at rest it pulls 350ma, (2.7 w @8.22v at the 2 cell lipo).
The reciever alone (reg and servos isolated) it pulls 40mA (approx 0.4W@8.22v). ie the receiver current draw is totally insignificant compared to the servos etc. If your system flattens its receiver battery much faster with spectrum compare to a 35/40 mhz FM system (or futaba 2.4) then its due to something other than the receiver - such as the faster response enabling you to load the servos harder (or the receiver has a serious fault!).

I disagree with that stuart about the spectrum being "guilty" and having to replace receivers.
You can have a hanger full of 60" planks running standard servos off 500mAh AA nicad packs and fly them all for a similar time as you would have on 35mhz and you will never see a volt dip reset of the rx.

Similarly you can fly up to a .50 size heli on a subC nicad pack with popular digital servos and you will never see a volt dip reset - not unless you are risking running the battery so low that the servos would probably stop or the gyrro give in anyway. Thats how I was flying my raptor 50 since until recently.

The spectrum merely shows up problems with poor quality power regulators.
If you use a lipo and quality regulator system with a nitro then you won't have a problem . Are there some reports of problems with a nitro running a lipo and regulator? I didn't read any yet (other than when the regulator falls apart due to poor quality).

When the heli is electric and running a lot of series lipos 5 or 6 in series - then the BEC/regulator is much more heavily loaded - stepping down from 22.2v. This is where all the problems have surfaced. But models like that are only a very very small part of the market. Trev already made an unfortunate demonstration that regulator electronics ained at electric flight are often not up to the job intended.

The models that switched from 35meg to spectrum and immediately crashed due to a BEC voltage dip (such as the big plank in our club) were already risking a brown out on 35Meg - they just didn't know how close they were. (that particular big plank was easy to get to reset by stalling just some of the servos).another example of a naff regulator not up to advertised spec.

You could argue that its the suppliers of these big powerful digital sevos that should be taken to task for not emphasising the need for an up rated power supply. The normal switch harness is only good for 3A, yet each big digital servo can pull 3A! (but you will actually read such warnings in the servo specs).

Also this gets a prominent link on the home page of spectrumrc.com and something like it has been there for a few months - so I don't see how spectrum can be blaimed for hiding the problem!

I do not regard spectrum as "guilty". I think their system is a very good product, and I appreciate that they have improved it further.

Its a bit wierd how the drip feed of comments on spectrum low rx volt problems has suddenly changed to a flood at the same time as the futaba id conflict problem is confirmed isn't it?

[Ashley Davis]

not to mention that the Futaba FAAST system resets at 3.5V as well......and your servos stop working before you get to 3.5V. Did Futaba publish that? Also Futaba reset time is longer than Spektrum even before the recent update.

I'm sorry but 2.4ghz is the single biggest and best breakthrough in the recent history of R/C and yet we are all bickering over the fact that it won't run on 3.5V.....yet the servos won't run on 3.5V either....where's that printed then, nowhere?

As to spektrum rx bleeding a battery dry.....I nearly fell off my chair laughing.

[Boggy]

[quote=Ashley Davis;104758]I'll only state this one more time but for everyone pointing a finger at spektrum and saying it's their problem...... IT ISN'T.
quote]

that was on page one ashley

now ill get some smart arse reminding me this is a forum and off we go again

[ChrisB]

Hey Ron,this is a forum

[moyesboy]

Ash you've got it completely wrong!


Its the futaba FASST not FAAST

[Boggy]

Hey Ron,this is a forum

roflmfao i knew it another six pages of coming up

[ChrisB]

Takes your mind off the weather though

[Boggy]

dosent it just! this is like swiming in the deep end fun though

[ChrisB]

Come on everybody,less of the

How about a

And a