Radio/RC Problems for 2007 Season

Have you been having problems with your radio connection and/or your RC? Recently, I replied to this thread (, but never got an answer on what we should do.

My biggest concern is that, as far as I can tell (and maybe I’ve missed something here), as of Update 11, IFI has failed to communicate relevant information. I’m perfectly willing to acknowledge that our problem could just be our problem, but IFI should (some time ago) either have said, “Yeah that code works, let’s call it the final version” or “Sorry that code doesn’t work, we’re working on something better.” This has been a hindrance to our investigations since we cannot adequately isolate a variable.

My reasons for bringing this up are simple: A) to find out for my team a way to fix this problem and B) if this is more than just our problem, to let people know about it.

Thank you for your time,
Paul Dennis

We also had radio problems but we quickly solved the problems with OUR radio. I dont know if it’ll be the same thing with you. We found out that the backup battery was somehow interferring with the radio, Once we got a different and BIGGER :smiley: battery problems solved. I’m not sure if this is why the radios are acting up but it worked for us. Hope this helps

We are still having a problem, does anyone know a fix for this. since we are aproching shipping date fast.

It seems that from our small sample around 40% of teams are having radio problems (no stats lectures please, I realize that’s not really accurate). Can we get some solutions here? I’m really frustrated by IFI’s lack of “pro-action”. I know they do a lot for FIRST, but they seem to not be doing much in this situation.


Everyone who’s had radio problems this year have called IFI about it, right?

We had the common problem of loss of signal. I followed the information on the IFI website FAQ forum then called for additional information.

We think ours is solved… what we did was…

  1. Installed the updated code
  2. Took the OI Radio and mounted it Vertical away from the controls.
  3. Moved the RC radio to the highest point available on the robot away from motors and structure (antena is clear line of site at all times).

Once we did this all the problems went away.

OHHHHH I also turned off my hallway motion detector used to warn me of persons that are coming to my shop.

Team 930 has been using a bigger/higher capacity battery and continues to experience problems.

Perhaps a thread bump will elicit more respondants to make this poll more statisticly significant.

We had the same problem with the radio losing signal when we were on the other end of the field. We changed the position of the radio on the robot and changed the cable just in case. It has not given us any problems since that move. It was lying flat beside of the backup battery and we moved it to the arm support and protected it with a cover.

Count us as having a lot of mysterious radio disconnect problems this year.
Team 1001.

In some cases we have been able to find something to blame it on (like having some other team on the same channel, or low batteries, etc.), but even when all those issues are resolved we are driving merrily along, the radio link fails, robot stops, toroid deposits on ground. sigh.

I guess that is an unexpected benefit of having the claw in the closed position when power is off? we set it up that way for autonomous :slight_smile:

Last night we had the robot take off pretty fast, out of control…on pretty much our only attempt to use the new radio. Finding a place to put the radio upright on the robot, away from metal, and always in LOS of the OI radio, is quite a challenge! but seems to be unnecessary when using the 2006 radio.

As posted in the previous thread (now bumped off the front page), our team had the same radio issues others have experienced. We sent the radios back to IFI, they reported nothing major wrong with them, but since getting them back we have had no further problems with cutouts. Last night/early this morning we drove the robot around full tilt, all mechanisms operating, and did not experience the same problems we had originally.

IFI is only capable of “pro-action” if you report problems to them. Let’s face it, people post to a forum only if they’re are having trouble, not if when they figure out the problem and everything is ok. Unless you call them and officially let them know something is wrong with your equipment, I would not expect them to continually refresh CD and write down the team #'s for everyone who has had a problem.

True, but they certainly knew there was an issue with the code for the cut-off. They released a new version of the Robot Controller Master Code. Part of my point is that this should either be declared working and no longer in beta, or they should have (by now a long time ago) released a new version.


This slightly bothersome radio issue has now almost cost us our arm/tube interface. We jammed a denso and keyang against hard stops. I’m suprised we didn’t strip out the worms in them. When controlling the arm with 2 potentiometers for our 2 articulations the thing just suddenly took off like a rocket, not listening to disable, and after some very scary noises, finally listened.

v14 master code,fully charged backup,

What do you mean by bigger/higher capacity battery? Aren’t you required to use the ones to spec in the manual? (and which battery–12v or backup?)

1501 had alot of problems last night. We’ve done everything we are suppose to do as Mike M said above. We are going to make another call to IFI today but I am not sure what good that will do. We’ve got ours mounted on the PVC flag pole away from metal etc…

What fixed our problem was swapping to the 2006 modems. The rest of our practice went flawless. No radio drops, no uncontrolled ramming…

I can’t even imagine what that is going to do with teams that have PID installed…with the error accumulating could be asking for crash em up bash em up and it won’t be your drivers fault…

If nothing else, we will sit and look pretty in the spirit of FIRST.

disappointed in Indiana…Chris Elston Team 1501

Assuming Dave’s referring to the backup battery, we can use one different from the KOP. <R73> states “any other commercially available 7.2V NiCad battery pack may be used”. You still are stuck with charging from this year’s KOP wall wart or the on-board circuit from IFI, however.

See this thread for a couple different ways to see when packet loss is occuring and when the RC has disabled the outputs.

For any motor controls with an “I” term in them, you’d at least want to prohibit the integrator from accumulating additional error, otherwise when the outputs are re-enabled, the motor speed/position will jump/lunge.

For this type of system, the new RC master code actually makes the situation worse. Rather than continuing on into the wall/door/locker/ankle that the robot was aimed at prior to the radio link going down, now it will pause, accumulate error, and then accellerate into the object.

Yes, I was referring to the NiCd backup battery.

Team update 13 includes a warning that the ‘charger’ included in the KOP is actually just a power supply and that it will overcharge the NiCd battery pack, and includes a warning not to leave the batteries unattended.

So the wording has been changed to say “a” 7.2V NiCd charger is to be used.

The poll lacks the response that fits for us, which would be;

“Yes, we have radio problems. But the fix is beyond our control.”

Just because you’ve mounted it on top of the flagpole, turned off all cell phones and motion detectors, had everyone hold their breath, and etc, and it appears to be working adequately doesn’t mean it is. Not when the old radios have performed so well for years without any hack fixes.

We have done none of those things because we believe the only fix will be to revert to the old radios. We’re working under the assumption that an Update will come any day saying just that. If not, then what happens the first week with six robots and six radios running in the metallic environment under high-powered lights in front of a cell phone toting audience should prompt a recall before our first week at GLR.

Very true…we are in the same spot.

Something that may factor into the problem here is that IFI’s supplier (Electrowave) can no longer build radios due to a lack of parts. (This is on another thread somewhere, but there are so many threads relating to these radio problems that I have lost track which one! :smiley: )

Even if IFI allows the use of the old radios this year, it is still a temporary solution, unfortunately.