what is required to change crystal - from FCC
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W4JLE - 12 Feb 2004 07:04 GMT From time to time I have seen that some magical annoiting must proceed legality to change a crystal. Turns out not only can you change a crystal, but if you want to change every componet in your R/C transmitter - Your legal,
The following is from the FCC website as to what services are exempted from requiring a commercial license to maintain a transmitter:
You do NOT need a commercial radio operator license to operate, repair, or maintain any of the following types of stations:
Two-way land mobile radio equipment, such as that used by police and fire departments, taxicabs and truckers, businesses and industries, ambulances and rescue squads, local, state, and federal government agencies. ******************************************
Personal radio equipment used in the Citizens Band, Radio Control, and General Mobile radio services. ***********Emphisis added ******************** Auxiliary broadcast stations, such as remote pickup stations.
Domestic public fixed and mobile radio systems, such as mobile telephone systems, cellular systems, rural radio systems, point-to-point microwave systems, multipoint distribution systems, etc.
Stations that operate in the Cable Television Relay Service.
Satellite stations, both uplink and downlink of all types.
Will Hicks - 12 Feb 2004 11:40 GMT That's true. The only requirement is that you are competent to do the work and have access to the necessary test equipment.
 Signature Will
http://www.willstech.com http://snurl.com/2mn - Our eBay Stuff
> From time to time I have seen that some magical annoiting must proceed > legality to change a crystal. Turns out not only can you change a crystal, [quoted text clipped - 24 lines] > > Satellite stations, both uplink and downlink of all types. Dan Thompson - 12 Feb 2004 19:50 GMT >The only requirement is that you are competent to do the work And WHO makes that call?
I took a test that was given by the FCC in 1969 to prove my competence, but now that license is not required for personal radio stuff. It is still required for avionics though.
Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL) remove POST in address for email
W4JLE - 12 Feb 2004 21:05 GMT There is no requirement of competency or any other requirement. I doubt that anyone without a smattering of knowledge is going to tear into their new 10 ch. JR just for grins. So I guess we can say it is self regulating.
The chains of regulations are cast off, let's change them crystals!
> >The only requirement is that you are competent to do the work > [quoted text clipped - 6 lines] > Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL) > remove POST in address for email C.O.Jones - 12 Feb 2004 23:03 GMT > There is no requirement of competency or any other requirement. I doubt that > anyone without a smattering of knowledge is going to tear into their new 10 > ch. JR just for grins. I wouldn't bet on that! Having the money to afford the radio does not guarantee the smarts to handle it properly! To include cracking it open to see how it works!
Pat Patterson - 14 Feb 2004 02:47 GMT The presumption of intelligence is a dangerous thing.
Presume abject stupidity and then enjoy the pleasant surprises when they occur.
> There is no requirement of competency or any other requirement. I doubt that > anyone without a smattering of knowledge is going to tear into their new 10 > ch. JR just for grins. So I guess we can say it is self regulating. > > The chains of regulations are cast off, let's change them crystals! Dr1Driver - 12 Feb 2004 13:42 GMT >From time to time I have seen that some magical annoiting must proceed >legality to change a crystal. Smart comments aside, thank you for the clarification. Dr.1 Driver "There's a Hun in the sun!"
Rich Lockyer - 13 Feb 2004 02:40 GMT >You do NOT need a commercial radio operator license to operate, repair, or >maintain any of the following types of stations: [quoted text clipped - 16 lines] > >Satellite stations, both uplink and downlink of all types. This is all true, however, it only applies to the need for a commercial radio operator license. You still need to verify that the transmitter is operating within it's design specifications.
Spectrum analyzers are getting cheaper, but you aren't going to be able to use it at the field after swapping a crystal.
For that matter, you can get a Hitec Eclipse 7 with Spectra for $200. Do it right or don't do it at all.
--- Rich http://richlockyer.tripod.com/
Six_O'Clock_High - 13 Feb 2004 05:55 GMT > >You do NOT need a commercial radio operator license to operate, repair, or > >maintain any of the following types of stations: snip
> This is all true, however, it only applies to the need for a > commercial radio operator license. You still need to verify that the [quoted text clipped - 8 lines] > --- Rich > http://richlockyer.tripod.com/ ROFLOL!
The 21st century version of "Dial-a-Crash. If you don't believe me, tell me how to find out what channel the radio was left on last. Not a very important issue you say? I guess not, as long as it is not your channel.
This radio system comes with a whole set of operational problems I have never heard resolved. Like how do you tell everyone else you are on channel 12 when you don't have a flag for it, and yesterday you were on channel 53. The biggie I got from a conversation with another is remembering what channel YOU put the radio on last week. Hence, the D-A-C remark.
W4JLE - 13 Feb 2004 07:59 GMT So if you buy a new transmitter with a different crystal, what would be different.
You get the new frequency pin, if only to keep someone else from crashing you.
I don't care if some of the nervous nellys on here never change a crystal. The facts are it is both safe and legal to do so.
> ROFLOL! > [quoted text clipped - 7 lines] > The biggie I got from a conversation with another is remembering what > channel YOU put the radio on last week. Hence, the D-A-C remark. Rich Lockyer - 13 Feb 2004 09:44 GMT >The 21st century version of "Dial-a-Crash. If you don't believe me, tell me >how to find out what channel the radio was left on last. Not a very [quoted text clipped - 5 lines] >The biggie I got from a conversation with another is remembering what >channel YOU put the radio on last week. Hence, the D-A-C remark. Each of my planes has it's own frequency, denoted by a number somewhere on or in the plane. As a cross-check, the model name in the radio includes the channel.
I have pins for all channels that I use for the field that requires it. The other fields only require a marker.
BEFORE I turn on, I remove the Spectra and verify the channel.
Like I said...
Do it right or don't do it at all.
--- Rich http://richlockyer.tripod.com/
Doug McLaren - 13 Feb 2004 16:21 GMT | The 21st century version of "Dial-a-Crash. If you don't believe me, | tell me how to find out what channel the radio was left on last. You pull the module out (if the things to adjust are on the inside, I'm not sure) and see what channel it's dialed to?
| This radio system comes with a whole set of operational problems I | have never heard resolved. Like how do you tell everyone else you | are on channel 12 when you don't have a flag for it, and yesterday | you were on channel 53. You make one flag for each channel you might use? (Your `you don't have a flag for it' restriction is pretty arbitrary. People with non-synthesized radios often don't have a flag either, though they probably should.)
Some people have a blank flag, and use a dry erase marker on it.
| The biggie I got from a conversation with another is remembering what | channel YOU put the radio on last week. Hence, the D-A-C remark. Of course, you also need to remember what model your radio is on. Exactly the same sort of problem, except that mistakes usually only crash your plane, not other people's planes.
These aren't really problems with the radio -- they're easily rectified by some dilligence on the part of the pilot.
The Tracker II has a scanner in it that won't transmit on a channel already being used. That's a pretty elegant solution to this problem, though it won't stop somebody without a Tracker from turning on when your transmitter is already on. But if everybody had one ...
The biggest problem I see with a synthesizer is the *possiblity* of causing a crash. If you have a non-synthesized radio on a given frequency, and you're sharing the frequency with somebody else, and they're flying and crash, they could accuse you of causing their crash by turning on -- and there's not really any way of disproving that, even though you know you didn't even touch your radio. With a synthesized radio, *anybody* could make the same accusation against you.
I guess that could be fixed by having a radio with an accurate internal clock that logs when it's turned on and off, and keeps track of what channel it's on each time ... but I don't think anybody does that. Or just leave your radio in the impound area, if there is one.
 Signature Doug McLaren, dougmc@frenzy.com Aren't you glad you use Dial? Don't you wish everyone did?
Six_O'Clock_High - 14 Feb 2004 06:01 GMT > | The 21st century version of "Dial-a-Crash. If you don't believe me, > | tell me how to find out what channel the radio was left on last. [quoted text clipped - 46 lines] > Doug McLaren, dougmc@frenzy.com > Aren't you glad you use Dial? Don't you wish everyone did? You noticed the same problems I did! That need for structure is exactly what makes that type of radio system dangerous in the hands of Frankie Fightpack. I prefered the old system that cost around $1300 because USUALLY folks spending that kind of $ on a transmitter are careful.
Rich, your points are valid but ignore the masses which is where our 'problems' will come from with this type of system. That was my entire point, nothing else was intended or implied which echos your "Do it right or don't do it at all." statement.
W4jl the difference is the D-A-C system can be changed from flight to flight and has NO need for TX crystals. I think the Tracker II does it for BOTH TX and RX. In short, our frequency flag system needs some help here.
W4JLE - 13 Feb 2004 07:55 GMT What in the world makes you think you need a spectrum analyzer after a crystal change? I have built complete transmitters from scratch for the last 50 years, and have never owned a spectrum analyzer.
What would prevent you from using it at the field? One need only run a standard range check. If that passes, you know you are on frequency.
No change of a crystal will cause excessive bandwidth etc. Don't make a simple thing complicated.
> >You do NOT need a commercial radio operator license to operate, repair, or > >maintain any of the following types of stations: [quoted text clipped - 29 lines] > --- Rich > http://richlockyer.tripod.com/ The Natural Philosopher - 13 Feb 2004 10:22 GMT > What in the world makes you think you need a spectrum analyzer after a > crystal change? I have built complete transmitters from scratch for the last > 50 years, and have never owned a spectrum analyzer. How did you check harmonic generation then?
Or dis you just hope the design itself was good enough to suppress them once peaked up?
> What would prevent you from using it at the field? One need only run a > standard range check. If that passes, you know you are on frequency. [quoted text clipped - 38 lines] >> --- Rich >> http://richlockyer.tripod.com/ reg - 13 Feb 2004 19:44 GMT >> What in the world makes you think you need a spectrum analyzer after a >> crystal change? I have built complete transmitters from scratch for the last [quoted text clipped - 3 lines] > > Or dis you just hope the design itself was good enough to suppress them once peaked up? Hey, he said he built them, he never gave any indication that they actually worked.. after he built them >:-) Probably just used 'em as ornaments.
Reg
W4JLE - 14 Feb 2004 04:36 GMT Standard amateur radio practice is all that's required. A simple band pass filter solves the problem of harmonics.
I suspect many Hams have never seen a spectrum analyzer, let alone used one.
It is only in recent years the prices have come with in reach of the average guy.
Most of us tuned to the harmonics with a receiver and confirmed they were sufficiently suppressed.
> How did you check harmonic generation then? > > Or dis you just hope the design itself was good enough to suppress them once peaked up? David AMA40795 / KC5UH - 14 Feb 2004 02:38 GMT If you have a Hitec, DOES NOT MAKE ANY DIFFERENCE - THEY WILL NOT SELL TX CRYSTALS ! ! ! ! !
David
>From time to time I have seen that some magical annoiting must proceed >legality to change a crystal. Turns out not only can you change a crystal, [quoted text clipped - 24 lines] > >Satellite stations, both uplink and downlink of all types. W4JLE - 14 Feb 2004 04:40 GMT International Crystal at http://www.icmfg.com/ will supply any crystal needs you may encounter.
> If you have a Hitec, DOES NOT MAKE ANY DIFFERENCE - THEY WILL NOT SELL > TX CRYSTALS ! ! ! ! ! [quoted text clipped - 29 lines] > > > >Satellite stations, both uplink and downlink of all types. David AMA40795 / KC5UH - 14 Feb 2004 23:13 GMT I've gotten crystals from ICM before. Question is - what load capacitance (CL) does one specify for Hitec usage??
Besides, at $20 for crystals from ICM, it is cheaper for me to send the 3 transmitters I want to change to Hitec - $15 each plus shipping AND I don't have to screw around with ordering from ICM and doing the retuning!!!!
David
>International Crystal at http://www.icmfg.com/ will supply any crystal needs >you may encounter. [quoted text clipped - 35 lines] >> > >> >Satellite stations, both uplink and downlink of all types. AndyOne - 18 Feb 2004 19:40 GMT The load capacitance of a crystal needs to be specified as parallel o series as well as the value in pico Farads. There is also the actua frequency the crystal oscillator is required to work at may not be th transmitted frequency. Some FM transmitters use 1/2 or 1/3 of th output frequency in order to more easily generate the required level o modulation and then multiply it up. You may be able to get thi information from the radio manufacturer.
I live in the United Kingdom and we've always been able to us pluggable crystals so getting them is as easy as going down to the LH and stating frequency and radio make.
It sounds like some paranoia as far as the FCC is concerned or som misinterpretation of the rules if, as stated above, it is legal in th US to change crystals.
Its quite easy to replace the crystal with a socket then plug them in just don't use one that's been soldered to it won't make good contac in a socket.
I wonder how many flyers in the US have done this and not told anyone.
Pluggable crystals can't be a problem because we in the UK had some o the most rabid radio regulatory rules such that CB was illegal unti the late 70's and when it was allowed, they put it on FM and o frequencies that no one else used.
my 2pence worth,
Andy. G8MQ
- AndyOn
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C.O.Jones - 19 Feb 2004 02:55 GMT What I suspect it is (on the part of the FCC anyway) is antiquated rules. Rules that had a valid purpose back when radio technology wasn't as technical as it is today. And changing a crystal required a complete re-alignment of the RF deck. But like most government regulations, the FCC has been unable to keep up with the times.
Chuck
> The load capacitance of a crystal needs to be specified as parallel or > series as well as the value in pico Farads. There is also the actual [quoted text clipped - 36 lines] > Visit us at http://www.rcgroups.com <------- Win free R/C Gear! > View this thread at rcgroups.com: http://www.rcgroups.com/forums/showthread.php?threadid=198834 W4JLE - 19 Feb 2004 05:59 GMT It seems to me they have kept up. They have said you can maintain your radio with no special license requirements. It is perfectly legal for you to change a crystal.
> What I suspect it is (on the part of the FCC anyway) is antiquated rules. C.O.Jones - 19 Feb 2004 12:20 GMT But when was this enacted? Or has it always been the case and we've simply been shammed by our own R/C industry? :)
> It seems to me they have kept up. They have said you can maintain your radio > with no special license requirements. It is perfectly legal for you to > change a crystal. > > > What I suspect it is (on the part of the FCC anyway) is antiquated rules. Dan Thompson - 19 Feb 2004 18:12 GMT >But when was this enacted? Or has it always been the case and we've simply >been shammed by our own R/C industry? :) 1980 under Reagan and yes you have! Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL) remove POST in address for email
Dan Thompson - 19 Feb 2004 18:26 GMT >But when was this enacted? Or has it always been the case and we've simply >been shammed by our own R/C industry? :) 1980 under Reagan and yes you have! Dan Thompson (AMA 32873, EAA 60974, WB4GUK, GROL) remove POST in address for email
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