Two months ago I bought a Futaba 7CAF on channel 23. I recently found out through my club that there is a guy that flies in his backyard close to the field that operates on the same channel and if I wanted to fly on that channel I would have to call him everytime I wanted to fly, which I'm not going to do. So I need to change channels. Is it possible to send the radio to futaba and have them change the channel or should I just try and sell it? Thanks.

You select the channel by changing a chrystal.
Chrystals are available at the hobby-shop, remember to get a matching channel chrystal for the reciver as well

It's illegal in the US to change transmitter frequencies. Not sure where you bought the equipment, but you could try exchanging it. Otherwise, I'd say sell it.
Dennis-

Yeah I thought I read something about it being illegal to change crystals in US. Would Futaba be able to change the channel? I bought the radio from Tower but since I already installed the equipment in a 4star they won't let me exchange it.

well you definitely own it now,i would check with your club to see what frequencies there on and go from their.and then send it back to futaba. I have heard of people changing there frequencies themselves but for me id would rather be safe then sorry and not put anyone in harms way.

In the US it is illegal to change the transmitter crystal. Most radios are specifically tuned for whatever channel they are on. You can change the crystal but range could suffer.

You can either buy a new one on the channel you want or send it back to Futaba and have them change it which would be the cheaper of the 2 options and would guarentee the radio be tuned correctly.

For the legal and just as important, safety reasons, I would not change the transmitter crystal on my own.

Radio South www.radiosouthrc.com is another place you can send it.

Thanks. I'll also post it up for sale and see if there is any interest and I guess I'll send out an email to Radio South and Futaba and see what it costs to have the channel changed.

If it is new, it will cost you less to change the channel than to sell it and buy a new one. Futaba will do it for you. Unless you just want a new one, change it.

Thats a good reason to go with PCM. The other radio wouldn't affect you, and after a while, he would get sick of crashing and maybe come join the club and fly so he isn't getting shot down all the time.

I know it's not enforecable and it may not help you much, but the other flyer you mentioned shouldn't be flying from his backyard less than three miles from an active r/c field in the first place! The onus is on him to comply with the AMA guidelines. If this guy continues to operate this way, there is the possibility of him causing a lot more problems in the future. What if he buys a new radio on a different channel? Perhaps I'm missing something, but why does the club not approach the individual about his frequency usage?

I think it's worth it to have the channel changed versus selling a 'used' radio for almost nothing and buying a replacement at full price.
Futaba will change the transmitter crystal and retune it for less than $30 including all parts labor and postage.
See a post in the Futaba factory support forum for the address, link to exact price, and details of what you need to do.
You can change the receiver crystal yourself as long as you stay in the 'low band' which is channels 11-35. If you go 36 or higher, you need to have the change done by Futaba.

If he's not an AMA member, he's not obligated to follow AMA guidelines. If a crash occurred and you (or any injured party) could prove that he caused it; someone might get money out of him.

Right. We live in the "sue" nation, so the 'lone wolf' flyer should understand that if he/she interferes with an AMA sanctioned field, there may be a lawsuit. That's why I specified the point was likely not enforceable. Why would anyone deliberately caouse a problem anyway?

I guess I'll keep it then and just change the channel.

Carrellh-Are you saying that I can change the crystal myself as long as I stay in the low band? Is this legal? I'd don't mind paying a little to avoid any legal issues in the future should something happen.

As far as the guy flying in his backyard, I don't know much about it other than the president asked at a meeting if anyone was on channel 23, at the time I didn't think I was. He then said that a flys in his backyard sometimes on channel 23 and that if someone was on that channel they would have to contact the guy to work a system out to avoid problems, too much of a hassle for me. Thats about all I know.

I think he's saying that you could change the receiver crystal yourself, as long as it's high to high, or low to low. You can legally change a receiver's crystal in the us, just not a transmitter.

Receiver crystals can be changed by end users. It's the transmitters that are covered by the rule to be retuned after a change.

Thanks, I read it too fast.

Guys, I've been in this hobby for 33 years and the new Futaba transmitters come with a module in the back that can be changed. The frequency is controlled by the module and can be changed as long as you stay within the band, either high or low band. If your thoughts are correct, every time I change the frequency in my synthesized Futaba 9ZAS, I am breaking the law. This is not so. If your transmitter has a frequency module in the rear the simply unplugs, then you can purchase a new module and plug it in and it will work fine, as long as you stay in the high or low band of your transmitter.

The RC frequency police gonna kick down his door if he does?

I have changed the crystal in my receivers and transmiters multiple times without problems. This is with JR. If it was that big of a deal they would not make the crystals so easily removed and have replacements for every frequency readily available.

What about the high end radio's that can change frequency electronically, not allowed to use that either? Sorry for the rant, but I hate RC frequency nazis.

It's OK to change a module or dial-up a synth frequency. It is NOT ok to change a transmitter crystal. The modules have the tuned circuitry along with the crystal (or synthesizer) inside one package. I don't think the 7C uses modules.

Fighterpilot is correctamundo-- To quote from my 9CAP Futaba owner's manual: "In North America it is against FCC regulations to change the crystal within the transmitter module to a different channel. All such transmitter crystal changes must be performed by a certified radio technician. Failure to properly tune a system to its new channel may result in decreased range and may also result in interference to other types of frequency users on adjoining channels." And one other thing nobody has yet mentioned--"DOING SO ALSO VOIDS YOUR AMA INSURANCE." The section also talks about non-Futaba modules are not FCC certified for use in Futaba radios and are against FCC regs to use and also voids AMA insurance. I'm sure that's probably also true for other brands, can only use their modules, etc.

It seems like such a small thing to pop a new crystal into your Tx, but it can really screw things up on adjacent freqs. due to crosstalk, bleedover and other types of interference. This is the primary reason it isn't allowed without retuning by somebody certified. The receiver doesn't matter because it's only "listening" for a signal, not broadcasting one.

jayselle,
The reason the transmitter crystals are so easily available here in the states is so that when your original xmtr crystal breaks, you can buy a replacement of the same channel. Not to be able to change it to some other channel. The reason the crystal is so easy to get to is that the radio manufacturers are making transmitters for world-wide use. They're not about to make millions of transmitter cases for international use and a different case with a non-accessible crystal just for the U.S. That would cost them more to tool up two different plastic molds, etc.
The reason we are so concerned with frequency integrity here is that the FCC has given us a specific set of channels to use and they happen to fall between public pager channels and are separated by only 10Khz. That's pretty close together. When someone changes the transmitter crystal and doesn't have their radio retuned to the new freq, it may bleed over to "their" public frequencies and they do monitor the airwaves. Once our hobby equipment starts to interfere with "their" equipment, they have full authority to do whatever they see fit to correct the problem. Will they? I've never seen it happen. I'm more worried of being shot down by a "bleeding" transmitter that someone carelessly modified. I now take a frequency scanner with me everytime I fly at my field. I shoot the airwaves, and if there is a hit on my channel, I will change the module on my transmitter to a clear channel.

Jesse

You could wait for that guy to start flying in his backyard. And then turn your transmitter on to "check the batteries". I'm sure he would be, uh, grounded for a while. Then you could fly safely for a couple days anyways.

I'M KIDDING!! I'M KIDDING!!

he has just as much right as the ama fliers at the field to fly... lets say you both have a 50/50 chance of crashing the other guy. he crashes your plane at the field, chances are no one gets hurt and no property is damaged. what happens if you crash HIS plane. the odds of someone getting hurt or property damage is probably higher. the worst part is that he can claim he didn't realize the problem existed, but you as an AMA member are completely aware of the situation, thereby entirely more responsible should something happen.

Ok, please someone correct me if I have this wrong:

A-it is illegal to change a tx crystal yourself, like the small pullout crystal found on the Futaba 6EXA
B-it is legal to change a module that houses the crystal like the Futaba 9C allows
C-it is ok to do B only if you stay within your low (12-34) or high (35-60) freq band

Question 1: I've read here many times that the low/high issue is probably just clever marketing. This thread seems to suggest otherwise?
Question 2: If Q1's answer confirms there is in fact a high and low band and once set from the factory, a device must remain in its band, can you plunk in a high band module into an originally low band tx, like the 9C again seems to allow?
Question 3: What about receivers? Must they also remain in their respective band?

Thanks guys. I've been looking for a definitive answer to these questions for a while now.