2.4 Frequency Issues

[skip241]

Hey Everyone! I've learned that this discussion page is the place to go if you have questions that can't be answered.

This past weekend I was sailing in the Sun City Regatta and after the first seeding heat, I lost control of my RMG 280DL sailwinch. Never lost control of my rudder. I am using Futaba 2.4 6EX radios.

After missing a couple of heats rewinding the sheets, reprogramming the winch, and swapping out the transmitter with a new one right out of the box, I tried again. Everything worked great until the last windward leg to the finish and the winch went bad again.

Rick West was kind enough to help me investigate the problem and we noticed a loose power connection to the receiver. That was corrected, sheets rewound, winch reprogrammed and the boat was placed in the water for the next heat.

Same problem near the end of the heat and I couldn't finish the race. This time Gerry Cobley and John Bottensek offered help. Eventually, everything was working again, on land.

When I turned on the transmitter for my next heat, Rick's electronics and another competitor's boat went crazy. When I turned my transmitter off, everything was fine again. (Rick and the other person, I'm so sorry for creating the problems.)

Sunday afternoon, I took both of my transmitters to the local hobby shop that completed the recommended testing as noted from a Futaba tech update. Both transmitters passed the test without any issues.

Before I go back to my old PCM radio, does anyone have any ideas?

1. I tried two different transmitters
2. I tried two different receivers
3. Could a short somewhere in the wiring in the boat be causing signals to be sent to other boats?
4. Could my old RMG 280DL be sending signals to other boats?

Any help would be very much appreciated.

Thanks

Skip Allen [?][?][?]

[Jim Hale]

Skip,
I can't help with the root cause of your problem, but I have been using the same combination of electronics (T6EX 2.4, 280DL) for a couple of years, without a problem. The only difference is that I do not program the winch. I use the transmitter to program the winch's endpoint adjustments and the failsafe position.

Hope this helps.

Jim Hale
1559

[RMDJBD]

Skip

Like Jim said I use the Tx to set my winch and all the boats I build.

There is one other thing I do is I turn off all failsafe systems, The winch and Tx.

Also when and if you do set the winch other than factory settings make sure that you use a fully charged battery since the program in the winch reads the voltage and sets the fail safe to that voltage.



Bob Dudinsky
R.M.D.MARINE

[Merv49]

Hey Skip,
Since you've changed both transmitter and reciever, I would suggest you find the common denominator in this situation. Perhaps it's the battery or some fault in your winch. When checking your reciever battery are you using a volt meter with a built in load? You say that the problem shows up after you practically sailed the whole race which leads me to believe it's a power/battery issue. Your fully charged 6 volt batt should read over 7 volts under load. Hope this helps.

Merv

[Rick West]

This to present the events in the matter for comment and for all to note if the occurs again.
There was some good conversation at the lake about this. This was need to sort through the matter for future reference. Here are the pieces to the matter and there are many:
1. Skip's TX had been dunked at a previous event.
2. He was having problems with control on the water and in the cradle.
3. The + prong holder of the plug into the RX was bent and the mating prong was not inserting but laying on metal connection. This produced intermittent power to the RX and hence his control problems. He did not know this when trying other things.
4. He changed batteries and repaired the power lead and to no avail.
5. He changed the TX and was going through a binding process when I was turning on my radio for a heat and the winch started oscillating between full out and broad reach (failsafe). This caused other issues in the sheetline system. A third party next to us was also turning on his radio and was hit with something funny and it went away. We were all within 20 feet of each other.
6. Skip turned off his system and mine would work okay. I cleared the lines and got in the water. While sailing to the start line skip turn his system back on and I lost control of mine and in the course broke the bow block from it mount.
7. Skip packed up and left while I repaired the sheetline system.
8. When I returned to the water after 3 DNS there were not more issues.
Speculation is that with three systems in close proximity and one that was attempting to bond, two system crossed paths. This may have left a code imprint on my RX or TX that created the second incident.
Also of note and very interesting, were comments that some airplane groups have a binding process at a day meet. This to have sequential turning on of the 2.4 systems but not all at once. Then they all leave the systems on all day. We turn ours off when in from a heat. Just something being done for a reason, whatever prompted it.


...94

[geeks2you]

I have started some extensive research on the internet as well as getting a hobby shop manager involved to see what he can come up with from manufacturers. There are a few questions to further clarify the situations that Rick posted.

1) only 1 of Skip's radios had been dunked. It is important to know if he started with the dunked one or changed to the dunked one. Skip?

4) Rick, when you turned on your systems, did you flip on the boat power (thus the receiver) first or turn on the transmitter and wait for it to power up (light the green port on the spectrum broadcaster on the back)? The later is the way I see almost everyone powering up in practice.

I have still yet to find a technically detailed description of the spectrum binding process and how Futaba may differ from other manufacturers. Also, everything I can find so far for very large events where there is a high concentration of radios seems to go through an extensive bind/check sequence.


Eric Olson
Atlanta Model Yacht Club
AtlMYC.org

[Chuck Luscomb]

Spoke with Skip earlier today. Seemed that he might have had a few problems that contributed to the big issue.

1-We think he may have had a low voltage issue with battery and or connections or both.
2-The RMG might have had the battery monitoring turned "on" which he will change.
3-He might not have the RMG and the RX wired to the battery independently. He thinks he has the rx down stream of the RMG which is the standard set up. This may have contributed to the problem as well.
3-With all the swapping and binding, it is possible that his radio bound with the other two RX's but that is still under investigation.

He is going to check these out and let us know.

Chuck
#84

[skip241]

We have answers, we think.

Winch Problem: Fresh, overnight charged batteries were used when programming winch in failsafe mode. Failsafe went into affect after a few heats and the voltage dropped. Solution: Turn off all failsafes.

Radio Problems: Several sources think I binded with Rick when I was swapping out transmitters and receivers not realiziing issue was winch related. It's not suppose to happen but that rarity probably happened with me. Solution: Don't bind radios in close proximity of others.

Thanks to all who helped with this problem. As I mentioned before, this discussion group can respond to most questions.

Finally, to those reading Rick's account and were either not there or don't know me, Rick's details are 100% accurate. However, he did not mention that I helped him from start to finish with the first repair and passed on parts from my personal "stash" on the second repair. Sunday morning I called and offered to reimburse him for expenses related to the problems I had created. He politely refused. I don't think of myself as a "break-em and leave-em" kind of person, or at least I hope I am not.

Thanks again everyone! Have a great week!

Skip [:D]

[greerdr]

I am really sorry I missed this event.Our best of the best were obviously there.
Maybe we should institute a sequential "On" to the 2.4 freq so the radios' search is less prone to conflict.I suggest in place of our old "radio check" we turn on by sail number each A.M. and insure capture of our Rx.

R.C.Greer

[bigfoot55]

In the similar experience I had, the problem did not occur untill much later in the day and there was only one fleet. It nay be that turning on in close proximity to another skipper at any time is a potential problem, not just first thing in the morning.
Take a look at the back of the radio also to be sure the transmitter has found channel before turning on the rec.

[Rick West]

My apologies Skip, I was dealing with the report and not meant to ignore your assistance. Skip stayed to assist in the repairs needed to the sheetline system and provided parts I did not have. This was not so much to get into the regatta but to be ready for the next one. My stuff lives in a vehicle between events.

This incident was not his fault. There is something to be learned here and that is important.

Skip is top sportsman with all the considerations toward competitors and his relations. Among many things he does for the Class he also provides a hull to the NCR most years. He was featured in a past Newsletter and is appreciated.

Turning on the TX first and then the RX is standard RC radio protocol no matter the brand or system used. I think Toms suggestion to check the TX for a green light is excellent advice. I am going to test leaving on the system during the day and monitor the power levels accordingly. This kind of issue with the winch running full bore back and forth is devastating to slack lines in the sheetline system. It is also devastating what it does to your regatta score.


...94

[skip241]

Thanks Rick! Glad everything is back to normal in your speed machine.

Skip [:D]

[Jim Hale]

If I may append a few words to this topic (which may or may not help Skip):

As one who has dunked and tried to rescue more than his share of transmitters, I can attest that you can get them to work for a day, a week, or even a few weeks. In the end, though, they will start to work in strange and sinister ways. Usually just before the start of the first race. Ask me how I know.

I am told that this is due to the contaminates from the pond that get onto the circuit boards. No amount of flushing and scrubbing can completely remove them. After the transmitter has completely dried out, it only takes the "right" combination of humidity and temperature to reactivate the contaminates, and cause all manner of confusion for the Tx. The contaminates have no conscience - they will go wherever they want to.

Futaba T6EX 2.4 transmitters are available on Ebay for about 70 to $90, if you are patient.

Jim Hale
1559

[Rick West]

See a report filed with the Class by Dave Ramos regarding issues with Futaba 2.4 GHz radio system 6EXAS on the home page of the Class site in Latest News.

...94

[Rob Guyatt]

Hi All,
Just surfing about the forums before heading to the lake for the day and came across this this interesting thread.

I'm puzzled by the interference problem between 2.4 GHz radios. I understood that a Tx could not bother an Rx that is not bound to said Tx. Also, am puzzled by the idea that when binding how an Rx that is NOT in binding mode can be bothered by someone else's radio when that someone else is binding their Rx.

Skips troublesome Tx was Futaba 6EX. yes/no?? When binding the Futaba system, There is no "bind mode" for the Tx like there is for Spektrum. For Spektrum the Tx is turned on into bind mode and so is the Rx. To bind a Futaba Rx to Tx all that is done is the little bind button on the Rx is pressed at any time after it is turned on. Unless this somehow turns the Rx into a transmitter to talk to the Tx about climbing into bed together I don't see how that causes a problem with other radios. Does anyone know the exact technical operation of the Futaba binding process?

Rick I'm sure won't mind me agreeing with him that Skip was not to blame for Ricks sheeting system failures. If SmartWinch setup mode is used to set travel and not just Tx end point adjustments then no amount of interference from other radios will cause the sheeting system to fail because the winch is limited to travel between the boats normal sheeting system limits.

Bob's point about making sure that the battery is charged when running setup ONLY applies IF you WANT to turn battery monitoring ON. If you just want to set end points or end points and travel then just turn the winch off before going into the battery monitoring section of setup then no change to the existing setting for that parameter.

I think one of the problems that can occur at the pond side is that when a problem occurs with the boat and the skipper thinks they need to redo settings in the winch and the battery is already down below the detection level for the number of cells and then go through battery monitoring setup unnecessarily as well. Then the winch thinks it is say a 5 cell pack instead of 6 and the winch goes to low battery failsafe sooner than it should.

I have simplified this in the E models by putting the battery monitoring setup in a separate setup mode. This means that to change battery monitoring setting the user no longer has to go through end point and travel adjustment just to get to battery monitoring setup.

It is a loosing battle I fight trying to convince skippers the last thing they should do when troubles occur is redo winch settings. There's a 99.9% chance that they don't need to. It only distracts from finding the real cause of their troubles.

On the point about dunking Tx's, My son dropped my 6EX 2.4 GHz in the lake (salt water) over a year ago. We pulled the battery out, took the back off, run it under a tap for a few minutes, shook the %$#%$ out of it then left it in the sun for a few hours before trying it out again. Still using it to this day. A club mate has done the same to his 6ex 2.4 TWICE (way clumsier than my son)and his is still going. Interstingly I have seen a couple of other 2.4 GHz radio brands similarly drowned and neither ever worked again. Perhaps they didn't apply the required amount of %$#%$ shaking [:)]

Rick would you mind giving me the link to Dave's Futaba report? Thanks.


Rob


Rob