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HITEC FLASH 5 CRYSTAL QUESTION

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Old 07-03-2007, 09:21 PM
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kenny k
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Default HITEC FLASH 5 CRYSTAL QUESTION

Hi I am new to the forum and really just getting started with flying gas planes.
There is an airfield just down the road from where i live and the guy's at the field are helping me get my first gas plane together
and one nice man gave me a hitec flash 5 system x radio that is on ch 45 the problem is one of the other guy's has the same frequency as mine other than waiting my turn my question is this can I change the crystals in my radio or do I have to send it off to have them changed. when I got the radio this man new who I got it from and was sweating bullets in fear thinking I might turn on my radio while he was in flight so being new to the field I don't want to make waves.
They do have a table that we can put our radio's on but I just want to do away with the problem altogether.

THANKS FOR ANY HELP.
KENNY K.
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Old 07-03-2007, 10:26 PM
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Default RE: HITEC FLASH 5 CRYSTAL QUESTION

In order to change the transmitter crystal, you need to send it to someone who can test that the radio is transmitting properly after the crystal change and make the necessary adjustments if it's not.

Edit: if this is a second hand radio, sending in the transmitter and receiver is a good idea anyway. The service shop can confirm they are working correctly. This is preferable to discovering they're not when your plane is in the air.
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Old 07-04-2007, 04:49 AM
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Default RE: HITEC FLASH 5 CRYSTAL QUESTION

Let me start by offering a big disclaimer starting with "IF"

"IF" you ignore all the doom and gloom warnings of various regulatory bodies etc there is ZERO reason why you can't change channels provided you stick with Hitec TX crystals.

Now, once you have made a crystal change it is worth getting the radio tested just to ensure there is nothing untowards going on. If any adjustment is required it's a basic retune which can be done on the spot.

Locally (Australia) they test for accuracy on channel, bandwidth spread (usually less than 20Khz), and signal strength. From what I've seen it's a case of someone with some basic test gear (usually a ham radio guy) doing these tests. I've seen 100+ radios tested with not one failing....many having had channel changes. In fact, I've yet to ever hear of a radio failing the test.

I had a Flash 5SX and changed channels. It retested perfectly with no retuning required.
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Old 07-04-2007, 07:05 AM
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Default RE: HITEC FLASH 5 CRYSTAL QUESTION

Its not doom and gloom, in the US you are advising him its ok to violate the law.

The fine is 10 thousand dollars per occurance. There's commercial users in between our channels and its a dangerous and illegal practice.
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Old 07-04-2007, 07:34 AM
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Default RE: HITEC FLASH 5 CRYSTAL QUESTION

My comments were related to 'will it work' rather than 'is it legal'. I thought I made that very clear with my disclaimer.

People associate 'non-legal' as 'doom and gloom' despite technical realities. While I do not encourage anyone to break their local laws there is technically no reason why an appropriate crystal/channel change should't work.

What's the US requirement for radio certification? Does the US body mandate radio testing, regardless of channel swaps? The Australian MAAA requires all radios to be certified although there is no actual law mandating it.
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Old 07-04-2007, 07:49 AM
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Default RE: HITEC FLASH 5 CRYSTAL QUESTION

Yes its quite clear, changes to freqency determining components can only be done by an authorized repair station or person with the ability to check output.

PLL (synthesized) tuning is fine, you arent changing components.

Module based transmitters are fine if you change the whole module as they contain all the tunable components.

Crystal swaps are illegal.

The FCC really doesn't care if you knock yourself out of the air, or another modeler for that matter, but the commercial users pay big bucks for the very crowded spectrum space over here and that would get the feds attention in a hurry. Also since the swap is illegal, if God forbid something did happen and there was an investigation that turned up an illegal freqency swap, the persons insurance would likely wash their hands of it.

For the cost of sending in a radio to get it checked over and tuned correctly it just isn't worth the risk.

This only applies to the 72 and 27mhz bands. The 50 mhz ham bands can do what they want because they have the band to themselves.

Also not to steal Chucks thunder, but he sent a radio in that he had bought used that had an illegal crystal swap and they found that the output was on the lines of 50 percent of what it should be, a quick tune up solved the issue.
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Old 07-04-2007, 07:53 AM
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Default RE: HITEC FLASH 5 CRYSTAL QUESTION

Nothing against you Raven but the reason Chuck, Rodney, Ken and I among others jump on these posts is because advice for people to disregard the law and do what they want, especially here in the US, could jepordize the good relationship we have with the FCC and cause problems for everyone.

Aero modeling in general is being watched with raised eyebrows, we dont want to bring on any unwanted attention.
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Old 07-04-2007, 09:48 AM
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Default RE: HITEC FLASH 5 CRYSTAL QUESTION


ORIGINAL: The Raven

Let me start by offering a big disclaimer starting with "IF"

"IF" you ignore all the doom and gloom warnings of various regulatory bodies etc there is ZERO reason why you can't change channels provided you stick with Hitec TX crystals.
WRONG! The reason you should not change channels, on your own, in the US is because it CAN interfere with frequencies that are between our channels. I find it odd that anyone would criticize our regulatory body, the one who has to deal with the mess when people decide they know better than the experts, for putting regulations in place to try to prevent interference.
Now, once you have made a crystal change it is worth getting the radio tested just to ensure there is nothing untowards going on. If any adjustment is required it's a basic retune which can be done on the spot.
Yes, it is basic for someone with the equipment and knowledge. The possibility of having something "untowards" happen is THE REASON (which you stated didn't exist) why one shouldn't change the crystal on their own here and why our FCC requires that we send transmitters to a qualified person to change the crystal.
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Old 07-04-2007, 09:53 AM
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Default RE: HITEC FLASH 5 CRYSTAL QUESTION

ORIGINAL: The Raven

My comments were related to 'will it work' rather than 'is it legal'. I thought I made that very clear with my disclaimer.

People associate 'non-legal' as 'doom and gloom' despite technical realities. While I do not encourage anyone to break their local laws there is technically no reason why an appropriate crystal/channel change should't work.
YES, there are technical reasons why it won't work! Radio South checked out a radio I bought from someone else. The former owner had changed the crystal to a different channel. The transmitter output was only 50% of spec. The other reason is that it can cause the radio to be off frequency, such as is described in [link=http://www.bergent.net/crystals.html]Swapping Transmitter Crystals[/link] by Peter Berg.
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Old 07-04-2007, 09:56 AM
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Default RE: HITEC FLASH 5 CRYSTAL QUESTION

ORIGINAL: BarracudaHockey
For the cost of sending in a radio to get it checked over and tuned correctly it just isn't worth the risk.
Exactly
This only applies to the 72 and 27mhz bands. The 50 mhz ham bands can do what they want because they have the band to themselves.
Applies to 75 mhz also.
Also not to steal Chucks thunder, but he sent a radio in that he had bought used that had an illegal crystal swap and they found that the output was on the lines of 50 percent of what it should be, a quick tune up solved the issue.
I should have read your post before I posted.
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Old 07-04-2007, 11:03 AM
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Default RE: HITEC FLASH 5 CRYSTAL QUESTION


ORIGINAL: The Raven
While I do not encourage anyone to break their local laws

Which is precisely what YOU sir are doing. You and irresponsible US flyers who would listen to you are indeed putting our (in the US) free and unlisensed use of these bands at risk. But then agine sir you really don't need to think about that, do You?

John
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Old 07-04-2007, 02:17 PM
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Default RE: HITEC FLASH 5 CRYSTAL QUESTION

If you are interested in the full text of the regulations concerning this matter they can be found at:

[link=http://www.access.gpo.gov/nara/cfr/waisidx_04/47cfr95_04.html]FCC Title 47, Part 95 - Personal Radio Services[/link]

Copied 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. 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.

Copied from FCC regulations concerning this issue

[Code of Federal Regulations]
[Title 47, Volume 5]
[Revised as of October 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 47CFR95.221]
[Page 539]
TITLE 47--TELECOMMUNICATION CHAPTER I--FEDERAL COMMUNICATIONS COMMISSION (CONTINUED)
PART 95_PERSONAL RADIO SERVICES--Table of Contents
Subpart C_Radio Control (R/C) Radio Service
Sec. 95.221 (R/C Rule 21) How do I have my R/C transmitter serviced?
(a) You may adjust an antenna to your R/C transmitter and you may make radio checks. (A radio check means a one-way transmission for a short time in order to test the transmitter.)
(b) You are responsible for the proper operation of the station at all times and are expected to provide for observations, servicing and maintenance as often as may be necessary to ensure proper operation. Each internal repair and each internal adjustment to an FCC certificated R/C transmitter (see R/C Rule 9) must be made in accord with the Technical Regulations (see subpart E). The internal repairs or internal adjustments should be performed by or under the immediate supervision and responsibility of a person certified as technically qualified to perform transmitter maintenance and repair duties in the private land mobile services and fixed services by an organization or committee representative of users in those services.
(c) Except as provided in paragraph
(d) of this section, each internal repair and each internal adjustment of an R/C transmitter in which signals are transmitted must be made using a nonradiating (``dummy'') antenna. (d) Brief test signals (signals not longer than one minute during any five minute period) using a radiating antenna may be transmitted in order to:
(1) Adjust a transmitter to an antenna;
(2) Detect or measure radiation of energy other than the intended signal; or
(3) Tune a receiver to your R/C transmitter.

(Secs. 4(i) and 303(r), Communications Act of 1934, as amended, 47 U.S.C. 154(i) and 303(r), and sec. 553 of the Administrative Procedures Act, 5 U.S.C. 553) [48 FR 24890, June 3, 1983, as amended at 49 FR 20673, May 16, 1984; 63 FR 36610, July 7, 1998]

[Code of Federal Regulations]
[Title 47, Volume 5]
[Revised as of October 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 47CFR95.222]
[Page 539-540]
TITLE 47--TELECOMMUNICATION
CHAPTER I--FEDERAL COMMUNICATIONS
COMMISSION (CONTINUED)
PART 95_PERSONAL RADIO SERVICES--Table of Contents
Subpart C_Radio Control (R/C) Radio Service
Sec. 95.222 (R/C Rule 22) May I make any changes to my R/C station transmitter?

(a) You must not make or have anyone else make an internal modification to your R/C transmitter.
(b) Internal modification does not include:
(1) Repair or servicing of an R/C station transmitter (see R/C Rule 21, Sec. 95.221); or
(2) Changing plug-in modules which were certificated as part of your R/C transmitter.
(c) You must not operate an R/C transmitter which has been modified by anyone in any way, including modification to operate on unauthorized frequencies or with illegal power. (See R/C Rules 9 and 10, Sec. Sec. 95.209 and 95.210.)
[48 FR 24894, June 3, 1983, as amended at 63 FR 36610, July 7, 1998]

[Code of Federal Regulations]
[Title 47, Volume 5]
[Revised as of October 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 47CFR95.645]
[Page 561]
TITLE 47--TELECOMMUNICATION
CHAPTER I--FEDERAL COMMUNICATIONS
COMMISSION (CONTINUED)
PART 95_PERSONAL RADIO SERVICES--Table of Contents
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.
[53 FR 36789, Sept. 22, 1988. Redesignated at 61 FR 28769, June 6, 1996, and further redesignated at 61 FR 46567, Sept. 4, 1996; 63 FR 36610, July 7, 1998]
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Old 07-04-2007, 02:20 PM
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Default RE: HITEC FLASH 5 CRYSTAL QUESTION

Now with that being said I will point out the RCU rules on illegal activities

PIRACY OR UNLAWFUL ACTIVITIES:
This community forum is a place for ideas and constructive participation, and not a place to violate any laws or to discuss illegal activities. This type of activity includes, but is not limited to, advocating or asking for information regarding software piracy or unauthorized emulators of software or hardware, sharing or distributing viruses, licenses, registration information, software keys, "cracks," or other information designed to do harm to or allow unlawful access to any computer hardware, software, networks, or any other systems. Please refrain from posting this kind of message.
Now since the original poster lives in the US I will say that this arguement is over as it is illegal in the US to change the crystals in the transmitter himself, and it should be sent in to have this done. While this may be ok in other countries it is indeed illegal here. Any "encouragement", "tips", "tricks", or "we do it all the time here" conversations in this thread only encourage others to break the law here in the US. RCU does not promote illegal activities therefore I am going to close this lock this thread.

Ken
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