carrellh

Here is Futaba’s position on crystal changes. JR, Hitec, and Airtronics all tell the same story. AMA tells the same story. Maybe they’re all wrong. I do not know. I am an AMA member and I fly at an AMA chartered club. I will not risk myself or the club financially by violating the AMA rule against changing a crystal.

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

How do I change the frequency of my transmitter?
For a module unit: to change the frequency you simply remove the module and replace it with a module on the new channel. You can even change 'bands' (IE 72MHz to 75MHz). All radio frequency circuitry is in the module so there is no need to 'retune' after a module change. (However, the receiver cannot be similarly changed to change bands. If you go to a new band you MUST buy a new receiver on that band. Please see the note below regarding crystal changes, which is valid for ANY receiver where you are changing within one frequency band.) DO NOT attempt to change transmitter frequency by changing the crystal within the module. You must use a module which is properly tuned to the frequency desired.

For a unit with crystals: We CANNOT recommend changing crystals to a different frequency. Changing the crystal on your transmitter is illegal unless you have the proper license. The FCC has established guidelines for the modeler's safety and for the safety of spectators. For safety and FCC reasons we must request that both TX and RX be sent to the service center to ensure proper crystal change and retuning to the new frequency. Crystal based radios cannot be converted to another band without parts replacement, and may not be able to be converted at all. Certain radios can be converted, for example, from 72 to 75MHz. Please contact the service center for any other conversions.
The applicable Federal Regulation is as follows:
TITLE 47—TELECOMMUNICATION COMMISSION (CONTINUED)PART 95—PERSONAL RADIO SERVICES

Subpart E—Technical Regulations
Sec. 95.645 Control accessibility.
(a) No control, switch or other type of adjustment which, when manipulated, can result in a violation of the rules shall be accessible from the transmitter operating panel or from exterior of the transmitter enclosure.

(b) An R/C transmitter which incorporates plug-in frequency determining modules which are changed by the user must be certificated with the modules. Each module must contain all of the frequency determining circuitry including the oscillator. Plug-in crystals are not considered modules and must not be accessible to the user.

======== end of Futaba quote =========

So, why can I pop the crystal out so easily if I’m not allowed to “access� it? Since the same transmitter is sold in countries where there is no FCC, the manufacturers came up with a way to comply with the US regulation but still be able to market products globally.

The crystal is actually glued in. I guess that satisfies the FCC. It’s easy to break the glue joint and remove the crystal, making it easy for a non-US customer to change crystals. Some people like to remove the crystal from a transmitter if it is the ‘student’ box on the end of a trainer cord.

MerlinL14

I think we established that about post #4

carrellh

?

sfsjkid

In the US, to my knowledge, the channel spacing is not as wide as in other countries, and I have experienced one case where TX crystal changing has caused some interference. Now, since it is allowed in other countries, most manufacturers in the name of cost savings have chosen to glue the crystal in. Unfortunately, this is not a very robust glue. The manufacturers are catching on and slowly see TX's made for the US having molded in covers.

Here's some additional info on one FCC case,

FCC Affirms Hefty Fine for Midwest Amateur Accused of Intentional Interference

NEWINGTON, CT, May 8, 2003--The FCC has affirmed a $12,000 fine against Technician-class Amateur Radio operator Scott E. Kamm, N0UGN. Kamm's station was in Waterbury, Nebraska, at the time he was cited last fall, although the FCC granted his February 27, 2002, application to change his mailing address to a location in Sioux City, Iowa. The FCC released a Forfeiture Order May 7 alleging willful and repeated interference, broadcasting of music and failing to identify with his call sign. The FCC's Kansas City office had released a Notice of Apparent Liability for Forfeiture (NAL) on January 24, but Kamm never filed a response, the FCC said. The Commission ordered Kamm to pay the fine within 30 days.

Responding to complaints of continuing interference on the input of a 2-meter repeater, FCC agents monitored the machine's input frequency last December 9. They observed a very strong signal on 146.31 MHz "consisting of music, sound effects and unmodulated carriers" and no station ID. The FCC said the transmissions were interfering with amateur communications already in progress.

The FCC used direction-finding techniques to determine that the source of the signals was Kamm's residence in Waterbury, Nebraska. The next day, an FCC agent monitored the same sorts of transmissions, tracked the source to Kamm's residence, and inspected Kamm's amateur station.

"The agent found an amateur radio transceiver capable of operating on 146.31 MHz," the FCC said. Kamm claimed no transmissions were made from his station and that he used the unit to receive only. Based on its evidence, however, the FCC Kansas City office determined that Kamm "willfully and repeatedly" violated FCC Part 97 rules "by causing intentional interference, broadcasting music and failing to identify with his station call sign."

From

http://www.arrl.org/news/stories/2003/05/08/100/?nc=1

This topic has been beat to death, RCG has a sticky RCU should have one too.

http://www.rcgroups.com/forums/showthread.php?t=94580

Bax

My Feedback: (11)

Congress created the FCC and gave it the power to regulate the airwaves and enforce that regulation. The position of legal people familiar with the FCC regulations of the R/C service all agree: You may NOT change the channel of your transmitter by just changing the crystal. This is also the FCC's position.

Transmitter crystals may plug in, but they must be secured from casual use. This means that they are in an enclosure that requires tools to access, must be glued-in, must be soldered in, and so on.

Anyone who continues to insist that the FCC cannot enforce such a regulation is incorrect. They can...and have done, but they don't usually go around with antenna-laden trucks to look for violators unless there's a complaint.

Please, please, please realize that the Radio Control Service is just a small part of the FCC regulations. The entire body of CFR47 deals with the FCC. The different parts, sub-parts, paragraphs, and so on are all interwoven with cross-references and more cross-referenced.

Bottom line? According to the FCC and legal advisors who know what they are talking about, you may not just swap out the crystal of your 72 or 75 MHz transmitter and change its frequency unless you can certify that the transmitter complied with the parameters of its Type Acceptance. If you do swap out a crystal without such certification you are in violation of the regulation. The FCC can confiscate such equipment and levy fines. Yes, you can appeal, and it goes before an FCC Administrative Law Judge. Further appeals would then go to the Commission, and then to the Federal Courts. Make no mistake though, the FCC CAN levy fines and enforce that levy.

Jackster00

Interesting can of worms (so to speak) I opened. Actually. at my home field, changing crystals was brought up after a fellow member was offering a NIB 7C Futaba (one of 2 he'd bought) for sale for $110. I've known this guy for a few years and have found him to be an honest person. He personally said nothing about my lament that it was the wrong channel, but everyone else there had their own opinions. I know very little about radios and actually could see nothing wrong with taking one crystal out and putting another one in. It seemed at first blush that having to send the TX in, was just a way for the mfr. to bleed more money out of us. I went to Futaba's website and read up on this, which mentioned the FCC rule. Again, being highly skeptical of the Govt., I decided to ask the question here. I think that having the choice of simply buying a crystal and installing it, and setting myself/club up for a possible lawsuit (and losing the AMA insurance) IF something were to go terribly wrong, sending the TX in, and paying $20 plus $8 for their shipping charges and additional shipping to get it to their shop, or paying $160 for a unit from the dealer with my channel already on it, for the few sheckels difference, I'll just go the safe, sure route and buy from my "favorite store".
Thanx for everyone's contributions. Jackster

sfsjkid

I applaude your decision. Yes, its a topic that comes up regularly. Here is a search of 'changing crystals'. I gave up after a while.

http://www.rcuniverse.com/forum/m_40...tm.htm#4085535
http://www.rcuniverse.com/forum/m_40...tm.htm#4091051
http://www.rcuniverse.com/forum/m_40...tm.htm#4097264
http://www.rcuniverse.com/forum/m_38...tm.htm#3856924
http://www.rcuniverse.com/forum/m_37...tm.htm#3712032
http://www.rcuniverse.com/forum/m_33...tm.htm#3377517
http://www.rcuniverse.com/forum/m_33...tm.htm#3301235
http://www.rcuniverse.com/forum/m_32...tm.htm#3232253
http://www.rcuniverse.com/forum/m_32...tm.htm#3248523

redfox435cat

you've finally changed your stance on it

This is how every single agency in the US works from the the local police force to the CIA and FBI, Fish and game CHP FCC and every other 3 letter orginization we've created. This is the technically your using that is false. If what you say is true then technically nothing is illegal in this country because the people physically upholding the law don't have the final say which is just whack. When your taken to court your are defending yourself against the FCC in front of a courtroom judge if it comes to that. coming out and say they have no power because of this is wrong. It's due process. They do have the power to check your equipment and your required to surrender it to them, I love repeating myself[:-]

nothing, I like the UK it's just your basing how your legal system works and confusing it with how ours works. You simply haven't grown up with our judicial system. I don't mean anything buy it or have any problem with what your saying other than it sightly skewed with a bit of partial truth.
OK I think I've beaten this to death

dacaur

From futaba's website:
How do I change the frequency of my transmitter?
For a unit with crystals: We CANNOT recommend changing crystals to a different frequency. Changing the crystal on your transmitter is illegal unless you have the proper license. The FCC has established guidelines for the modeler's safety and for the safety of spectators. For safety and FCC reasons we must request that both TX and RX be sent to the service center to ensure proper crystal change and retuning to the new frequency.

From one of hitecs user manuals:
e. Changing Crystals
Changing crystal to avoid conflicts with other aircraft is possible where permitted. (You must check your local rules before doing so. For example in the US the FCC prohibits the changing of transmitter crystals on 72 and 27MHz).

from JR's website:
Can I change the crystal on my transmitter or module?
No, it must be returned to the authorized JR Service Center per FCC regulations.

From airtronics website:
Q. Can I change channels on my transmitter and receiver without re-tuning?
A. Radios equipped with frequency modules can be changed to another channel by replacing the tuned module with another tuned module. Radios not equipped with frequency modules can not legally be changed without re-tuning the radio to the specific channel. Not only is it against FCC regulations but more important it may shorten your range and/or cause interference with someone else's radio that could therefore cause personal injury.

CB36

Hi everybody;
Is a 7c a "module" TX or not?
Thanks!

vertigo72480

I guess I'm just lucky. As a Ham, I don't really have to worry about frequency conflicts. 6 meters is very quiet. Also, being a Ham, I have friends who have advanced diagnostic equipment in their homes, so we just play with radios for fun. We've changed frequencies, checked power output, and generally just analysed the crap out of these radios and had a lot of fun doing it. I have intentionally taken a radio from the highest channel to the lowest and haven't seen any deviation from the frequency printed on the crystal. But, remember, we have federal licenses and advanced equipment.

tuwood

Nope, it just has a crystal plugged into the back. You cannot change the TX crystal.