tx / rx question
 

I have a JR Quattro radio on ch #33. I want/need to switch this due to another guy at the field being on the same channel. Normally we are out there at the same time, and since he has 10+ planes on ch 33, and I have just one, it's easiest for me to switch.

The question is, can I just swap the crystals in the rx and the tx to another channel? I've read conflicting reports that say I can't change the tx crystal at all, or that I can change it if I remain in the same band. Which is it?

Thanks!

RE: tx / rx question
 

Send it in............

RE: tx / rx question
 

It is illegal (FCC) to change the transmitting frequency, period. I know that people do it, but you run the risk of losing range or bleeding over onto other channels.

It is fine to change receivers crystals.

Sell your Quattro and buy another one. Shouldn't cost you much to change if you buy a good used one.
Dennis-

RE: tx / rx question
 

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RE: tx / rx question
 

with a futaba all you gotta do is change the crystal but if your receive is low band just make sure its Low band Channel 11 through 35 and not high band crystal then it would be wrong. I dont think JR has high and low band so I'm assuming that you can get whatever channel crystal you choose. I'm not 100% sure just wait a lil bit longer and you'll get better responses.

RE: tx / rx question
 

It is illegal. If you want to make sure, just call your local FCC office and tell them where to come and issue the citation and confiscate the illegal equipment at. Just because you can sometimes get away with something does not make it correct or smart. Sort of like jumping into a lake without knowing what is below the surface. They sell crystal sets so that you can take the new equipment to a proper facility and have it properly tuned and not expect the facility to stock every possible crystal. Yes, odds are in your favor but it's still not right. Synthesizer modules deal with a whole different type of freq generation and the modules have been proved and certified by the FCC to comply with all appropriate regulations. It is not illegal to jump bands in Futaba receivers but you may sacrifice range and therein lose a plane. [:'(]

RE: tx / rx question
 

Here you go.... here's Futaba's warning about swapping TX xtals, along with a quote of the FCC regulations...

http://www.futaba-rc.com/faq/service-faq.html#q2

RE: tx / rx question
 

And that does apply to Montana too.

BTW- I do have the appropriate license, FCC Commercial Radio Telephone General and I don't tune my own because I don't have the appropriate manuals to do it properly.
I tune/align aircraft radios for a major airline EVERY day but a man has to know his limitations and what he is allowed to do by law. I am NOT going to endanger my license and my job by tuning a transmitter without the proper information available. For me the would violate FCC & FAA regulations and could lead to dead people in a worst case scenario.

RE: tx / rx question
 

Bruce, no one said for you to endanger your license and tune an RC radio, so I don't see your point there, sorry.
Then I guess a LOT of people should be in jail.........HAHAHAHAHA Sheesh guys, chill. Mental note to self......No more Highly illegal Crystal Swaps...Everyone listen up on this. Don't do it!!! My only gripe is THERE should be more adverts on this, and warnings in view, not in the "fine" print. I am not the only one, who has done this out of "Lack of knowing" not trying to break the law. Period. I think Futaba/JR, etc, etc, should list this warning on each TX crystal they sell, most people do not know this, as we all do not work on radios and deal with the FCC. Isn't the purpose of RCU to Educate, not Flame? Dang. Now I/We know not to do this and knowing is half the battle. Good Day.

RE: tx / rx question
 

No flames were intended by me, only to be emphatic. I fully agree that it should be in large print on the front of the manual but how many of us read those either except when we have a programming question?

Sorry if anyone felt flamed, just don't want to see any lost planes for such a little thing.

Bruce :)

It would help if they didn't put the crystals in the front of the radio and make it so easy to do.

RE: tx / rx question
 

Bruce, I agree. I as one, did not know this. I thought you just had to send it in, for them to tune it, so you wouldn't loose range or have any issues with the electronics, I did not know it was illegal, honestly and a lot of people do not. I think the TX crystals should not be sold then, and if you want to change the channel, then you have to send it in, and they install the crystal, not buy it from Tower and then the owner sends it in, too easy to just use the radio, etc. Maybe just some better warnings about changing the TX channel with our radios and accessories.

RE: tx / rx question
 

Going to repeat the same message here, but as said a few times above. DO NOT CHANGE IT YOURSELF. There are people around that will tell you to just go ahead and do it, it's easy. That's true it is easy, but think about this. You could go down to the gas station and fill your tank and drive away without paying. You would probably get away with it, but are you 100% sure you wouldn't get caught?? Legal issues aside, changing the crystals could de-tune you radio to the point that it doesn't function 100%. This is like the legal part of it, you would more than likely be fine doing it yourself, but is it worth the chance of it reducing the range of your radio? Think about this (you may not have planes this expensive, but I'm making a point.) --- Dave Patrick Ultimate Bipe-$400, YS 140 4-stroke engine-$550, misc parts-$100, high torque servos - $225, Airtronics flight pack-$115. That's almost $1,400. Cost of sending your radio in to have it retuned - $30+shipping. In my book it's cheap insurance to losing the plane.

IMHO those who tell you to do it in spite of the laws and common sense are acting irresponsibly.

RE: tx / rx question
 

Thanks for the answers. I'll have to wait to send it in as currently it is in my only flyable plane. Once I get my 4* finished and get comfortable with that, the JR will go in to have the crystal changed. That'll give me the chance to get it fixed too (throttle trim slider doesn't "click" anymore, just slides up and down smoothly).

RE: tx / rx question
 

The reason they make the crystals so easy to change is because it's not illegal in the rest of the world, only in the US. [:o]

But our radio frequncies are so crowded that the FCC has had to regulate them closely.
Dennis-

RE: tx / rx question
 

If you had Futaba, you would not have to go through all that as long as your frequency change remained on one side of the high or low band.

I do not know how JR works on this but is a waste of money and time and its a hassle for some. As far as being illegal, you have a better chance of being hit by a 1 inch meteor than having the FCC come knocking on your door. Compare the legalities to this, its also illegal to go 31mph in a 30 mph zone.

Whatever you do, make sure you do a range check

RE: tx / rx question
 

Snoop Doggy Bag-
"If you had Futaba, you would not have to go through all that as long as your frequency change remained on one side of the high or low band."
This is true only with respect to the receivers.

"I do not know how JR works on this but is a waste of money and time and its a hassle for some."
I will have to acknowledge you may not know how JR works and that YOU consider it a waste.

There are many laws on the books that are hassles and considered wastes of time and money. They are none the less still laws. If you do not like them, campaign for a change through the AMA frequency committee. I attempt to obey the laws every day and NO I don't always manage to do it. But I don't blatantly flaunt them like you endorse.
These are my last words on this subject as the laws ARE clear
May I suggest you do not encourage others to disregard the laws
BTW- if there were to be an accident, this could also be used to show negligence and possibly give the insurance companies (including AMA) grounds to drop coverage and leave you liable for all damages.

RE: tx / rx question
 

buy the hitec optic 6 with the spectra module. you can set the tx to any channel you want. and it also can be changed to positive shift. then you can sell your jr.
http://www2.towerhobbies.com/cgi-bin...&I=LXGZS6&P=ML

RE: tx / rx question
 

That says it all right there. It's just not worth the risk to save a few bucks. For the cost of 30 bucks (2 gallons of fuel) you might save someone's life. And, you might not even realize it. You might keep your radio from bleeding into frequencies that are not RC--in other words, your plane might fly great, and you might not shoot anyone down, but are you sure you're not interfering with a construction crew down the road, or something else where someone else could potentially get hurt? You're risking everything you own, and putting your family in financial jeopardy if your insurance drops a claim.

BTW,
Ignorance is NO excuse of the law. That, by the way, is law. So it doesn't matter if you know or not. These are not wal-mart toys we're dealing with here.

RE: tx / rx question
 

oh! oh! oh! Okay! Listen Bruce, I am so sorry for being so ignorant, unsafe and thinking only of myself. I am not going to waste my time mincing words with you since you appear to know everything. You must be "the one" that every field of pilots experiences. My reply was in regards to receiver part as the subject was. I gave you no cause to flame me and I will not accept it. Go get a rise from somebody else who cares.

RE: tx / rx question
 

If it has a module in the back of it, you can legally change that module to change the freq. You just can't change a crystal in the module.

I have sent them in before to be changed, but it has been a long time. The turn around on Futaba is usually really fast. The last time I sent something to them was a receiver I screwed up and they had it back in less than 15 days. It was nice, and because it was only a week old, it seems to me that they didn't even charge me, even though it was my screw up that hurt it. That was nice of them.

RE: tx / rx question
 

On the Futaba, all you need to do is replace the module in the back to change channels. All the RF goodies are in the module.

RE: tx / rx question
 

Of course not all of the Futaba's have modules. But I imagine most know that. It would certainly make life easier.

RE: tx / rx question
 

It is clearly stated in the Futaba manuals that transmitter crystals can only be changed by an authorized service center. It's also been discussed here many times and almost every time, one or more people make it obvious that they knew what they were supposed to do, but changed the crystal on their own anyway. I do agree that there should be clear instructions provided with the transmitter crystals.

Edit: forgot to mention, it's also been mentioned several times that hobby shop owners, who DID know better STILL advised customers to change them on their own.

RE: tx / rx question
 

Yes, Chuck, trying to sell the radio which is on a different channel than the buyer already uses - they're concerned about their profit ONLY not about the buyer and other RC-ers who may suffer the consequences.

BTW a radio which is not retuned after a crystal change may shoot down a plane using an adjacent frequency channel while flying perfectly fine the plane on the same channel.

RE: tx / rx question
 

I was flying my foamy yesterday, and when I did a low pass in front of the flight line, I got some severe glitches... a buddy of mine was next to me with an illegally retuned TX. Was it his TX, or was it my crappy feather RX, or a combination of both... I'll never know for sure! I do know that when I flew without him next to me with his TX, it flew fine! When I landed it, an severe aileron glitch hit, flip it sideways, and snapped my stick fuse on the foamy... nothing an hour and $2 worth of materials can't fix, but I'd hate to cause more severe damage to someone else's plane because I was too cheap to retune my radio properly...

RE: tx / rx question
 

while on the ground, turn on your tx/rx, and have your buddy then stand next to you and turn his on. see if you get any glitching. You might want to disconnect the motor (electric?) just in case.....Would hate for a stray signal to fire that puppy up!

RE: tx / rx question
 

Thanks, but I just retired my Hitec Feather RX (cheap, single conversion RX) to my spare parts bin, and installed a Hitec Electron 6 (good quality dual conversion micro RX) in my foamy... I doubt I'll have any more problems now. I've flown several different dual conversion RXs (including Electron 6 RXs) with that same guy & his "illegal" TX, and never had a problem. I've also ordered two more Electron 6 RXs for my other two foamies that are under construction. I'm not going to cheap out on RXs any more, not even for foamies...

RE: tx / rx question
 

It would be interesting to do an experiment that compared the effects of the illegally switched transmitter with one that was legally on the same frequency. Many of those in the willfully ignorant camp contend that the FCC is being over controlling and that there is no risk of interference. Perhaps some real life evidence would help convince some of them.

RE: tx / rx question
 

Unfortunately, the only experiment some people will understand is when their (or someone else's) plane gets shot down. And then will deny they had anything to do about it rather than admit they illegally changed the freq of their transmitter.

RE: tx / rx question
 

Kind of sad isn't it? A person who spends thousands of $ on airplanes won't fork up less than $50 to ensure their transmitter doesn't shoot other people's planes down.

RE: tx / rx question
 

Yup. You're very right. And the sad part of it is the only real thing we can do is land and get out of the way until that person leaves, or leave ourselves. Not a good situation. We've been lucky at our club.. so far.

RE: tx / rx question
 

Well, here's my "theory" on what's happening with my buddy's illegally tuned TX...

What I know so far...

1) We both flew cheap single conversion RXs
2) My RX had little to no glitching when I didn't fly near his TX
3) My RX had severe glitching when I flew near his TX
4) His RX had no glitching when he flew near my TX
5) I've flown dual conversion RXs near his TX with no glitching

I suspect that he has enough leakage into adjacent channels with his illegally tuned TX to screw up the cheap single conversion RXs, but the dual conversion RXs can reject this well enough not to glitch. His cheap single conversion RX doesn't glitch near my TX because I have a factory tuned Futaba module without any adjacent channel leakage.

If I still get the same glitching while flying with him after I switch to an Electron 6 RX, I'll definitely give him some grief about it... he's very good friend and flying buddy, so things will get resolved peacefully... :);)

RE: tx / rx question
 

The AMA Membership Manual on Pg 17 also calls for realignment after a crystal change, even if not changing freqs. EVERY crystal is different.

Violation of this would therefore be grounds to deny AMA insurance coverage IMHO if they were to wish to do so.

RE: tx / rx question
 

(Disclaimer) Well whatever the "negative" is that comes out of my remarks this time is not necessarily what i do or what i support, Its only what I see.

I was a military pilot from 75-95. Add on doing whatever it is I do now to include radio control, trucking, communications etc, not one time have I ever heard of or known anyone who received any form of letter or violation from the FCC. Nada! If I were to guess, I bet they rely on the locals to sort of "self enforcement" at around our level.

The FCC has its rules and the AMA has theirs. there is no way either department is going to know what anybody does with their radios unless something disatrous happens. There is no way your going to know what anybody did to their transmitter unless they tell you. 5 guys out flying, one gets glitched and it goes in. I would like to see anybody, say "I think it was me! I just changed the crystals for the heck of it and did not get it tuned!"

Anybody ever read that hugh poster on the AMA safety code? I did once and if you follow it, you may as well pack up and go home. As i recall a statement in their about flying a giant scale plane while a smaller one is in the air and some "distance thing" Whatever it was, you can't do it and yet it is done routinely.

I think the chances of you getting shot down are far better by some cheap $15 parkflyer in the area than some guy fooling around with his crystals.

RE: tx / rx question
 

I certainly am glad the people I fly with take safety and personal responsibility more seriously than those who make it seem that changing transmitter crystals without retuning is not a big deal. Who cares whether or not the FCC or AMA can enforce the rules? It's there for the good of everyone. People who ignore this rule are showing they have little concern for safety and a lack respect for their fellow modelers.

RE: tx / rx question
 

Thank you Chuck. I believe I'll just stay away from New Mexico. That will make at least 2 people happy.

RE: tx / rx question
 

:D

RE: tx / rx question
 

I just re-read the safety code. I could find nothing about flying giant scale aircraft in the presence of smaller aircraft. There were some items about keeping aircraft minimum distances from certain places/people for safety purposes. These all seemed reasonable to me and are also incorporated within my clubs field rules.

RE: tx / rx question
 

Maybe it was that 25ft rule or something. I don't rmember . I'm surprised they have not re written it regard the 40%planes and crowds or turbines. I am not knocking these but planes have tripled in size in the last few years. Who knows, but it'll happen

RE: tx / rx question
 

You just don't know when to quit do you. I have been making statements here based on fact and what I have seen. Where did I say that is what I do or support it. We have rules and regulations coming out are back end and their is a large percentage of people who don't care.

On my way to the field this morning I and driving past a older guy walking/exercising in the bike lane which is essentially part of the road. Less than 6 ft to his right is a perfectly good and new sidewalk!. Whats my point? Common sense say use the sidewalk but their are alway those who just seem to have a screw loose.

Just because I am telling the story does not mean I agree with this idiot walking in the street.