BarracudaHockey

My Feedback: (11)

Ok, lots of talk about firmware so here's the skinny for anyone thats curious.

There's 3 versions about and the way to tell which version you have is to link the system and get solid lights, interupt power to the reciever and power it back up.

1 of 3 things will happen.

1. The system will take 3 seconds to connect and the lights will be on solid. This is the oldest version and should really be updated.
2. The system will link instantly and the lights will come on solid. Better, but no brownout indication.
3. The system will link instantly and the lights will flash. Best.

fizzwater2

My Feedback: (61)

I don't think the DSMX receivers have the brownout indication (flashing lights) - I'd have to go back and read the info that comes with them.

DSM2, yes. DSMX, no.

BarracudaHockey

My Feedback: (11)

Thats correct, DSMX (the protocol) does not.

DSMX recievers when bound in DSM2 mode do have brownout indication.

Zeeb

My Feedback: (41)

Bingo!

Having had an experience with a little 50cc gasser where it was originally flown only with a then new JR X9303 and R921, I had nothing to compare flight characteristics since it was a new model from a manufacturer I'd never used. It always acted a bit funky on spins and snaps. The R921's had the original Quick Connect which got rid of the 3 to 5 second reconnect time in the event of a power brownout but no flashing light indication it had happened.

I sent all my rx's in for the Quick Connect version 2 update which has the flashing light indication, when it became available from Horizon. The first time I flew that model and landed it had flashing lights on the rx's. I couldn't believe it was possible as that model had a dual battery system from Duralite which was big enough it should have been able to handle a 35% size model. I checked the battery charge, looked things over for any obvious issues with binding servos, loose wires etc and couldn't find anything wrong so I flew it again and had flashing lights again on landing.

I took it home and ran every test I could come up with on the whole system including servo extensions, servo binding, switches, regulators, battery load test, checked the resistance on all the wiring and I could not find anything wrong. So I took it out and flew it again and had flashing lights on landing again. Took it home and ran through the whole process again and tried to make it fail on the ground but I couldn't do it on the ground nor find any fault with anything in the system. I flew it again and had flashing lights again. This time I took the fancy and expensive Duralite Li-Ion system out of it and replaced it all with a single 2300mah A123 using dual outlets.

Took it out and flew again, the snaps were better and so were the spin entries and I pushed it as hard as I could trying to work the battery and power system to it's max. When I landed; no more flashing lights. So I replaced all my fancy Duralite systems in the other models with A123's and haven't looked back.

The point being and I'm sorry it's taken so long to get here; flashing lights on landing (assuming they were not flashing when you took off...) mean a power interuption and just because you cannot find the fault nor duplicate it on the ground does not mean you didn't have that problem....

cloudancer03

My Feedback: (22)

these discussions always end up with spectrum units.I dont get it.I had 2 costly brownouts and switched back to futaba and with likely over a thousand flights not a single glitch not one!

Franco2fly

Okay, now I'm confused.

I thought that the old protocol was DSM2, and the NEW protocol, (that I have with all newer receivers including the 8 channel that came with my DX8 Christmas present) is DSMX...

To go a little further, DSM2  picks two frequencies on power up and sticks with them.  This is why it is the less reliable of the two protocols.
DSMX the newer protocol bounces between a number of frequencies hence the "X"  I don't know the dwell or bounce rate, or the number of
cells used. Don't know the BW of each cell or what the underlying modulation (FM/PCM/etc.) that is being used.  This is way down in the weeds.
Hopping between cells is what used to be called Spread Spectrum.  I would also like to know how the transmitter knows the receiver capabilities, unless it trys to use DSMX, but if the Receiver does NOT respond, the Transmitter picks 2 freqs.

I think in Radio Engineering terms the DS stands for Direct Sequence, and the 2 is what indicates the selection of 2 versus "X" indicating crossing multiple cells or channels.


KKKKFL

OobedoobeR

ok i will throw my two cents in. i have a spectrum 7 and had the same problems. i tested it and sent it alone with my recievers to the shop for testing. it came back with a new antenna and a note that
they found out that nothing was wrong. everything checked out ok. i then tested it. put it in a plane and made a brown out with it. the reciever never did reboot from the brown out. i turned the trans on then the reciever it bonded ok then i turned off the reciever and then back on to put into brown out as i was instructed to. it should have rebooted within a couple of seconds. fifteen minuets later it was
blinking and never did reboot. i did it several times and it never rebooted. i lost three planes on maden flight about eight minuets into the flight. just lost all controls suddenly. now the radio is an
anchor. well i may use it as a buddy box but no more spectrum for me. moved to futaba fasst eight channel. so if it dosent work to where you can trust it junk it

BarracudaHockey

My Feedback: (11)

Franco, what are you confused about?

Yes, DSMX is newer. Better? Thats a matter of opinion, certainly in a high RF environment or at a big (several hundred pilot) event its probably "better" but at 99 percent of the flying fields and events, DSM2 is perfectly fine.

BuschBarber

My Feedback: (2)

As we know, the term Brownout was a label given to a condition where the Rx voltage of a Spektrum receiver dropped below critical and forced a Reboot of the receiver, which then took more than 5 seconds before control was restored. Since then, a firmware upgrade was made available, which is now referred to as Quick Connect. This reduced the Reboot time to a second. The cause of the voltage drop was determined to be a sudden, large, current drain on the Rx battery.

A one second loss in communication between the Tx and Rx is not as significant as the Rx going into Failsafe, due to Loss of Link, such as due to Interference. I would think that it is less likely an aircraft would crash due to a Brownout Event than a Failsafe Event.

When in DSM2 mode, many JR/Spektrtum receivers have a blinking light that indicates the receiver has Lost and Regained power. The event was most likely a Brownout, but could also be due to intermittent connections in the Rx battery cables or Switch Harness.

Judicious use of the Flight Logger can, among other things, record the number of Holds (Failsafe Events) during a Range Test or a Flight. Between the Brownout Indicator Lights and the Flight Logger everyone should be able to get some idea of whether their radio experienced a Brownout, Failsafe Event, or both.

You can test your airborne radio system in your aircraft, using an H9 Current Meter or a Wattmeter, to determine it's susceptibility to Brownouts.

With any manufacturer's radio, there is always the chance that anyone can receive a defective Servo, Receiver, Gyro, Transmitter, etc.. If I continued to have problems with a particular manufacturer's products and the cause could not be resolved, I would probably buy from another manufacturer.

In 34 years of flying RC, I have used Futaba, JR, and Spektrum radios, as well as many Hitec receivers and servos. I have never had to stop using these manufacturer's products because I did not trust them to be reliable. When there was a problem, warranty and service took care of it. I have no personal experience with Hitec transmitters or Airtronics radios, so I cannot speak for them, but I have friends who use those products and find them just as reliable.

I am fairly sure that Every manufacturer's receivers can experience a Brownout if the Rx battery voltage drops below critical.

Unexplained crashes of aircraft are unnerving and stressful on the mind as well as the wallet. We all want to know the answer. Blaming every crash, of an aircraft equipped with a JR/Spektrum receiver, on a Brownout, does not make sense and in many cases (not all) can be ruled out using the tools mentioned previously. Just because only JR/Spektrum has Brownout Lights and Flight Logging included in tools and telemetry they sell does not mean Brownouts, Fades, Frame Losses, and Holds only happen with JR/Spektrum radios.

jmohn

I lost four very nice planes from "lock outs" caused by low voltage or bad connections. All the planes were a total loss and the receivers were fine once they were powered back up. This was several years ago and were some of the first that I knew of in my area. I worked with someone out here that helped develop Spektrum technology and we found if took 3 over 15 seconds for the receiver to reboot after this occured. We test dozens of new receivers and they all had this problem.

Soon after they came out with "quick connect" which eliminated the problem (for me at least) and I haven't had any issues since then. I was ready to change radios and start a law suit against them at the time

Fortunately both Spektrum and Horrizon both were very responsive and addressed the issues in a timely maner.


Jeff

mikes767

Hi Tony

I do alot of trouble shooting in my job and though it is possible you might have had an equipment problem for all those models and batteries , receivers and transmitters to crap out all on the same day the odds are astronomical check into any changes around your field.

Tony Iannucelli

My Feedback: (193)

Thanks Mike. Of course you are correct. I did the math as well. Four planes which means four ESCs, four different batteries, four different receivers (+ satellites), four different motors, and two different transmitters. As I said in an earlier post, I should have gone out that day and bought a lottery ticket.

I flew again today, four flights using the same transmitter and batteries, but a new airframe with ESC, motor, and receiver. Nary a problem. A different flying field. I've been a JR guy for 12 years now. I flew Futaba for 20 years before that, with other brands too, back when there was no "model memory". One plane, one transmitter. Anyway, as I also said before, never an issue with any of them. I only switched to JR because I started flying helis and JR servos were superior in the late 90s, in my opinion. I think the frequency hopping Futaba system is better than two frequencies JR/Spektrum uses. Seems JR thinks so too, with the new "X" software. I noticed Futaba didn't switch over to the JR system! But mine works very well, and I still use 72 quite a lot on PCM. NEVER an issue with pricey scale helicopters. I won't use 2.4 in them... but 2.4 has worked well for me for years.... right up until the other day..... Thanks again Mike. Tony

Franco2fly

Ok,
So I have the protocol's down, and I have only had one time when I thought I underwent a momentary loss of signal.  I attribute that loss to RF environment where the site was TOO close to a major airport with LOTS of surface search radar operating in the same range.  Now let me
move on.

I just joined a club that has a real Airstrip. It is well out in the country however, I want to return toservice aircraft that have been hanging on the wall for some time. Oneof my favorites is a pattern plane from the 70's. The question I haveis how to get signal into the body since it is a Fiberglass fuselage. Iseem to recall reading that 2.4ghz doesn't penetrate Glass very well.Is there an external antenna that can be purchased?

Thanks guys

KKKKFL<br type="_moz"/>

BuschBarber

My Feedback: (2)

Fiberglass is not the problem. Carbon Fiber fuselage's are the problem. There are receivers with antennas designed for Carbon Fiber fuselages.

Franco2fly

This thread has gotten a little slow, so I want to brag a bit. I saw someone say they used 3 different Tx/radios... Wow... here's my list:

first, Home built ControlAire Mule using S/n escapment then Babcock escapement (1964)
Citizenship AMAnalog proportional (3 channel)
Kraft
Logictrol
Airtronic (AM)
Airtronic (FM)
Airtronic (PCM)
Futaba (FM)
Futaba (PCM)
Specktrum Dx7
Specktrum Dx8

Stick a fork in me I think I'm done... I like the Dx18 with the sliders on the left and right, but the price is outta my league.

KKKKFL

AndyKunz

It's probably less than your Kraft or Logictrol cost you!

Andy

Franco2fly

I can still remember saving up for each.  The Kraft was the more expensive, the Logictrol was purchased off my first re-enlistment bonus(1967), and ran me $250 bucks.  I actually have those two out of order as the Logictrol was first.  I also left off the Japanese reed system I had prior to the Citizen ship analog system.  I've tried to find out the name of this reed system, but it's lost in the weeds of R/C history.  I can recall the box being blue anodized aluminum and it had 4 toggle switches(E/A/R/T 4 servos, 8 reeds).  Pushing a toggle up produced one tone down another and the Anco servo which was linear would push or pull.  While on the ground you could hear the reeds vibrate, and it sounded like a musical instrument.  I have to laugh at folks complaining about something as trivial as an alarm going off for in-activity....  What programming?

Seriously, the only thing that is a minor inconvenience for me after all these years is the lack of the analog type slide on the "5th" channel left side of the box, but even here, I can get used to using the Flap switch and mixing the flap/elevator functions.

Now for a serious question.  If I have a newer receiver, say like the one that came with the Dx8, can I force the transmitter/receiver to operate in DSM-2 or are they defaulted to DSMX?  I have no idea as to why one might want to use DSM-2 instead of DSMX, maybe someone will chime in.

KKKKFL

AndyKunz

On the DX8 you can force the transmitter into DSM2 mode if you want. Normally you leave it set to DSMX and it will then automatically select DSM2 or DSMX based upon what the receiver can do.

There are 2 reasons that I can think of to force DSM2 mode.

1) If you want to see the brownout LED flash. In DSMX mode, there is no flashing brownout indicator.

2) If you have a plane with two receivers, one DSM2 and the other DSMX. This might be the case if you had an old rx in your floats, for example, but a newer rx in the fuselage. If you want to have both work, they need to both be in DSM2 mode (they also need to be the "same type" of rx, ie AR6200/AR6210, AR6100/AR600, etc.).

Andy

Tony Iannucelli

My Feedback: (193)

I'll see all of your past radios and raise you a Heathkit 8 channel, an EKLogictrol, and a Proline. Bragging about this stuff only means we are old!
To the more important stuff. We flew again Tuesday morning and again on Wednesday at the same field where we had the problems described in the first post I made here. Tuesday we had two events of significance. My buddy Ron flew 11 batteries, four different planes, no blinking, no problems whatsoever. No changes were made to his equipment before flying. I flew 10 batteries, four different planes, no problems whatsoever. That's the first event. NO PROBLEMS. The second thing was that the county guy was monitoring the pump station. After flying we talked to him about his equipment and he gave us a quick tour. He is broadcasting on 219.353. I don't know what our frequencies are, but they aren't anywhere near 219 I would think. Second event, NO INTERFERENCE from the pump station we think. Plus the signal from the pump is broadcast every 20 minutes, and since we were there for four hours, I'd say the odds are pretty good we were flying at some point when the county was broadcasting.

We flew again yesterday, a total of 19 flights. No problems whatsoever, including a maiden flight on a RIFLE (holey moley batman), several Habu flights, three F-20s, and some Phase 3 F-16s too. A new record of 1,235 vertical feet was also set (with permission of the tower ).

Signing off guys. The problem day we had is history. Big mystery. Bermuda triangle ... Amelia .... you get the idea. We'll never know. Tony

Franco2fly

I'll see your Heathkit, and raise you and Ace galloping Ghost set up that I left off.  Yea I'm older than dirt, hehehe  Did you really own an EK Logictrol, I thought I was the only one that purchased one?

Even with massive power and potential harmonics, I cannot imagine 219 MegaHertz interfering.  My only link loss experience (and it has not been proven) came about at a site that was less than a quarter mile from an International airports runway, and "I think" the result of getting painted by Extremely High Power Radar operating in the 2.4gHz range.  Back in the 72 meg days, I did experience a link loss due to Multipath reflection from a water tower that was not all that far from our flying field.  To this day, I do NOT use full lenght Steel push rods for this reason.  Even the Aluminum wing struts on my Senior Telemaster have been replaced with Hard wood, just to genuflect to the RF gods.

KKKKFL

Tony Iannucelli

My Feedback: (193)

Yes EK, red box and all. Servos looked like they came from Erector sets. That radio was embarrassing if I remember correctly. Maybe bought it from Hobby Lobby in the early 70s. Maybe, can't remember.... which is another frequent event! I left out an original Tower radio too, back in about '75. Made by Futaba I think, so it doesn't count. T

Franco2fly

hahaha

But they were strong as a red brick.... and about the same weight.  I was trying to remember the other Japanese producer beside Futaba,  Not Sanyo,  I remember going back and forth between Futaba and Airtronics for years, but seem to recall someone else in the hobby.  I still have some Kraft servo's out in the workshop, and have been using the Airtronics standard servo's of which I must have 15 or 20 collected over the years.  There's something to be said for the old technology, still works.


KKKKFL

fizzwater2

My Feedback: (61)

Sanwa. I think they made (or make) Airtronics radios, but I could be wrong.

Franco2fly

Sanwa did make Airtronics, but I thought there was another.  Might be that Sanwa had their own box, plus they made Airtronics.  I always lusted after Graupner stuff when in Germany, did purchase some Multiplex servo's.  I think I've purchased my last New system with the Spektrum Dx8.


KKKKFL

BarracudaHockey

My Feedback: (11)

My first two channel glider radio was a Cox/Sanwa