2walla

My Feedback: (10)

Yes i have had a receiver have one channel fail. Flew it quie a while in a combat plane using a mix to an aux channel. All it takes is a crack on the circuit board to acause it to fail.

do335a

When it comes to electronics and just about anything for that matter, there are two categories:

1. those items which have failed

2. those which are about to fail

I've seen it happen with servos, batteries - both packs and cells, receivers and I'm just waiting for it with a TX. In fact. I suspect that there is an issue with my Futaba 9CAPS in the mixing.

Once there is a failure, the cure for me is the trash can. I'll never trust that component again. With RC stuff, the whole unit goes into the dumpster. Attempted fixes just make you feel better, giving a false sense of confidence. Reliability is lost. Too complex internally to take a chance losing a plane which costs considerably more than the cheapo failed stuff.

I'm also surprised that we don't hear more about TX failure. Look at any other electronic device or component, like full size automobiles, TVs, radios, computers - you name it. Those electronic things fail reularly, especially electronic ignitions and computers in automobiles. Can't count how many required repair or replacement in my automotive shop. So why would I expect to see a zero failure rate with a cheap radio control TX? I absolutely would not.

Junk that faulty TX and move along with confidence in your replacement until it bites the dust and then repeat.

raptureboy

Have you really looked inside a TX? Not all that complicated and if it's just a loose wire and can be fixed why throw out a $300- $400 transmitter? Batteries are one thing but transmitters; you can send your next one to me when your ready to junk it.

abufletcher

As it happens I already have a back up RDS8000 and I'm in the process of transferring all my model settings over to that one. I picked it up at Hobby People last December. At the time, I certainly didn't need a new transmitter, but the whole thing including an Rx, the Tx battery and a swtich was on sale for about $120. I've thought about "upgrading" to one of those expensive $300-400 transmitters (The Futaba 8J would do nicely), but with my WWI stuff I just don't need all the fancy functions and from what I read on the forums they seem to fail as frequently/infrequently as Airtronics.

abufletcher

Apparently, this problem has indeed been discussed before:

abufletcher

http://www.helifreak.com/showthread.php?t=346244

do335a

Yes I have - on numerous occasions. When I was younger and stupider, I even fixed those problems, broken sticks, crappy pots and all that sort of thing.

If it's a loose wire, there is a reason why that came loose. These things don't just happen on their own as if by magic. Usually, it's been a problem in a major chip, which leads to other problems. I have specific examples of that sort of thing too.

Into the dumpster. Not worth it for a couple hundred bucks against a several thousnad $$ and countless hours build time model. Oh, forgot. You guys are into BARFs. No prob. Just buy another. Mine are time , that non-renewable resource, so it's my life. Not worth the risk for a couple hundred bucks.

Dont' foret - time is your life. Spend it as you wish. That in fact is one of the major excuses for buying a BARF. Then spend more time making it right as opposed to just doing it right in the first place and being done with it.

abufletcher

So...I turn the damaged RDS8000 over to remove the 8 screws holding the back on...and the throttle/rudder stick just drops out on the floor!!! This does not inspire confidence. Once the back is off, the disconnected (red) wire is immediately apparent. Also apparent is what dinky wire they've used. I'm no electronics wizard, but these wires look like they are just waiting to fail. [:@]

I might go ahead and fix it...or see if I can get Airtronics to fix/upgrade it next August when I'm in the US (close to the ATX facilities)...but right at the moment I don't see me ever using this again on any of my precious scale models. The question is whether I can be certain that another brand radio (Futaba) is going to be better.

TFF

No brand is 100%.
Crack open the newer TX and compare to see if things look better. They may have a better or less stress wire routing. Crazy about the rudder/T stick; that kind of thing happens after a drop normally.
I keep resisting a new radio just because I think the quality of my older radios are better than the replacements I would be getting. Someday I will have too.

abufletcher

Certainly not a single one of my Japanese clubmates uses a Sanwa Tx. It's pretty much all Futaba and JR...with one or two HiTec.

abufletcher

For some time now I've felt I should be moving over (up?) to Futaba and the likely choice for my WWI needs would be the 8J:

http://www3.towerhobbies.com/cgi-bin...&I=LXBWGR&P=ML

Teus

Don,

Thats indeed a very weak point in this transmitter.

You can make it a bit more riggid by securing the wires to the print (after soldering back off course) with hott glue. Make sure that the hott glue enclose the wires completely and the print is fully covered. When done it should last much longer because the moving point of the wire is not anymore at the soldering point (weak) but in the coated wire

abufletcher

That sounds like a good suggestion. But I'm not sure I understand exactly where to solder the red wire. I think I'll just wait until summer to have Airtronics repair it.

So just what happened when the red wire broke? Did the ailerons just stay "frozen" in the position they were in when it broke? Did flight pressures move the ailerons around as I was fighting to save the model?

Teus

I think there are two posibilities:

1. Your transmitter still generates and transmitted the aileron signal in a certain fixed position You had nothing can do more than you already did..

2. Your transmitter lost the aileron signal anddon't transmit the signalanymoreto your receiver. Resulting in afailsafe on your aileron channel and the servo goes to the "hold" or a pre programmed position.

Thats why I always program a neutral position on all channels in my receiver,except the gas position, that goes to idle.

For example: IfI lost aileron signal frommy transmitter than the ailerons goesto the neutral failsafeposition. Model can still be flown and safe landed with rudder only control But if you lost elevator, than you have a bigger problem but maybe that can also be solved by playing with the throttle to control altitude a bit................ Still better than that all channels are in a certain "hold" position with a great deflection at the time of failsafe.

Just my 2 cents,

Teus

If I examine the close-upphoto correct than I see still a peace of the broken red wire soldered to the print..........

lopflyers

My Feedback: (12)

My opinion is you have two sensible options:

TFF

If the wire breaks in the TX, the TX is still sending the channel signal. You lose a wire like you did it would be like loosing one side of a pull pull cable for a mechanical analogy; one side works but the other does not, depending on the wire or you would loose both. The radio part is still working it just gets an errored signal from the stick. Failsafe only works when the TX signal is not readable.

abufletcher

This describes fairly well what I was experiencing. Anyway, all of this shows that crash analysis is sometimes helpful and can sometimes lead to a discovery that can prevent a future failure.

TFF

It is important to have some understanding of your equipment. When I was a kid doing this, there was still kits you could buy and make your own radio; many of the model magazine articles were on radios. There is still one you can build http://mstar2k.com/ I keep wanting to do it; live a childhood wish. Things like what broke and how to relieve the wire stress use to be a regular skill. Older radio adds would tout these things; now only programming seems to be important.

flycatch

My Feedback: (26)

Airtronics will deny it but you are not the first this has happened too. My friend had the same transmitter with the same problem you are describing. Traced it back to cold solder joints on the gimbal potentiometer.

jester_s1

This was an issue on the early RDS8000 radios. They went to a longer wire pretty soon to fix the issue, but it's become fairly common to put a dot of hot glue or epoxy on the joint so that the stiff soldered wire isn't flexing. Your gimbal stick problem happened to me too. It's clear to see in the picture that the plastic hole that the stick goes in has cracked. I think the left side stick is more prone to that because we tend to pull at the up and down ends a lot more on the throttle than on the right stick. I put a dot of medium CA on it and stuck it back in about 6 months ago. I haven't had a problem since.

raptureboy

Thats a big assumption. Not all of us are into barfs but some of us prefer not to throw away our money over a little problem like a broken wire. There are no guarantees even a new radio will give you any more success than the old. They all have pluses and minuses.

Teus

If you loose the wire from the gimball like Don experienced you loose both ailerons in a last known fixed position or dependingthe signal stillsend from the transmitter. The aileron channel has no input to the transmitter anymore. And like almost all transmitters these days we mix both aileronsto two output channels in the transmitter with one input. So if we loose the one and only input (gimball) than we loose both ailerons at the same time unfortunately.

TFF

With 3 wires going to the pot, you can either loose all or one direction depending on which wire comes loose. If the right two wires are still connected you will have one direction but no return. Once something happens, it is how the encoder interprets what happened. The radio part just transmits what the encoder says to do.

abufletcher

What is clear is that the ailerons didn't reset to neutral when the wire broke. Maybe if I had been flying level or in a mild bank, I could have continued on with 3-channel control, but I'm fairly certain that I as in the middle of an aggressive left turn.