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-   -   Question about Futaba 9c 50 mhz output. (https://www.rcuniverse.com/forum/rc-radios-transmitters-receivers-servos-gyros-157/557942-question-about-futaba-9c-50-mhz-output.html)

Damnathius 02-14-2003 10:59 PM

Question about Futaba 9c 50 mhz output.
 
I recently purchased a Futaba 9c on 50 mhz. Does it come standard at 1 watt power output?

Yes, I know about getting the Tech HAM license and am set up for the local March 1st test. :)

Thanks,

Dave

Lynx 02-15-2003 03:28 AM

Question about Futaba 9c 50 mhz output.
 
I doubt it's standard at 1 watt. You'll have to check with Futaba, and then see if you can find someone that can modify it legally. Keep in mind, having a HAM license gives you a permit to broadcast on those frequencies. If I'm not mistaken it gives you absolutely no rights to alter FCC certified hardware, and it's still illegal to do so. I haven't been through all the FCC regulations regarding HAM users yet but it's not a license to kill so to speak => Just a license to broadcast on legal hardware. You're still legally liable if any hardware you're operating is interfering with something else. BTW. If 50MHz is generally clean then don't bother increasing the wattage, it'll just drain a few hundred more milliamps from your battery. For almost all cases you want to use the minimum transmitter power that will give you a clean signal at an acceptable distance. If your transmitter is tuned properly and the spectrum is relatively clean, you'll have no problems getting proper range at the existing wattage.

Pilotsmoe 02-15-2003 05:35 AM

Question about Futaba 9c 50 mhz output.
 
I was told that it is between .5 to .75 watts.

Damnathius 02-15-2003 02:09 PM

Question about Futaba 9c 50 mhz output.
 
Thanks for the replies. I was just reading some other threads on 50 mhz and it was mentioned that they transmitted with more power than 72 mhz. I have no intention of modifying my radio to get more power, but was just curious if it was factory tuned that way.

Thanks again!

Whirley Bird 02-15-2003 05:52 PM

Re: Question about Futaba 9c 50 mhz output.
 

Originally posted by Damnathius
I recently purchased a Futaba 9c on 50 mhz. Does it come standard at 1 watt power output?

Yes, I know about getting the Tech HAM license and am set up for the local March 1st test. :)

Thanks,

Dave

Dave,
I spent hours on the phone in the last three days with Futaba,FCC and OET in MD.
Go to the URL below.
Look at the back of your TX.
You have a FCC ID number there.
Type in the first 3 letters in the first small block.
Then type in the remainder in the second block
Say you have a Sky sport.
Type in AZP then T4VF-50.
Don't forget the small dash and the frequency number.
A page will come up with some specs.
Futaba will not tell you anything and they set the power for what THEY think is enough.
Let me know how you make out. http://www.fcc.gov/oet/fccid/help.html#epc

amcross 02-15-2003 08:40 PM

Question about Futaba 9c 50 mhz output.
 
As I understood it, the equipment is not factory tuned differently for 50MHz, so it would be below .75. As I understand it, as a HAM you can turn the power up to 1W, and i think that's what you might've been reading about.

HAM operators are allowed to change crystals within their modules and crystals in non-modular transmitters.

Flyfalcons 02-15-2003 08:49 PM

Re: Re: Question about Futaba 9c 50 mhz output.
 

Originally posted by Whirley Bird

Futaba will not tell you anything and they set the power for what THEY think is enough.

So you think that a radio that is good enough for Futaba and everyone else isn't good enough for you? If so then you are seriously mistaken.

Whirley Bird 02-15-2003 09:11 PM

Re: Re: Re: Question about Futaba 9c 50 mhz output.
 

Originally posted by Flyfalcons


So you think that a radio that is good enough for Futaba and everyone else isn't good enough for you? If so then you are seriously mistaken.

.WOW,
Everyonr on grouch pills today?
All my radios are Futaba.
I just want to know why the 4FM is advertised as putting out the max power out allowed by the FCC when it only has an output of .289.
I have three on 72 megs and 1 for 6 meters.
All 4 are putting out the max power allowed by FCC.
The tower hobbies 4TH owners manual say it rated for 3/4 watt but the FCC ID site say it's 0.048.
Sounds like a TYPO to me but all my radios went to an electronic firm in Princeton,NJ and placed on the bench.
They eat batteries faster now so I;m working om my packs and building up 2,000 mil NMH packs.
They take longer to charge but they won't have the memory problem

Whirley Bird 02-15-2003 09:26 PM

Question about Futaba 9c 50 mhz output.
 

Originally posted by amcross
.
Ms Cross,
The 6 meter ham band transmitters are tuned for 400 mils from the ones I tested.
The tuning pot is easy to detect and (without giving hints) I can see why you keep them below the full rating.
They can go over the limit very easy but don't look that good on a scope.
I don't intend to go to deep into the more complex part of RC with computer radios.
The simple 6FM is tops for me and does everything I need it for and I have no problem with range.
Also the price for a full package in the TH catalog is SUPER! :)

Lynx 02-15-2003 11:25 PM

Question about Futaba 9c 50 mhz output.
 
amcross, can you please find the FCC regulation that says that? As I understand it you have to have a commercial license to do things like that, and that's a whole different ball of wax.

amcross 02-15-2003 11:26 PM

Question about Futaba 9c 50 mhz output.
 
Lynx,
Sorry, i'm really not in the industry any more, and those kinds of searches used to give me headaches! It is in the HAM segment, and they call it something funny. if you post a new question asking for it, someone will find it for you.

Lynx 02-15-2003 11:51 PM

Question about Futaba 9c 50 mhz output.
 
I'm taking my tech test in a few months, and to prepare for it I'm studying the FCC part 97 (Which covers HAM rules) so I'll find it eventually, I need to cause I'd like to know if I'll be able to do some stuff I want to legally or not =>

Mighty Mik 02-16-2003 02:02 AM

Question about Futaba 9c 50 mhz output.
 
It's worth reiterating that whole power out vs. time available on batteries thing.

I plan on flying slope, so i need all the time i can get. 3/4 watt vs 1.0 watt isn
't that much of a difference.

Damnathius 02-16-2003 04:31 AM

Question about Futaba 9c 50 mhz output.
 
Whirley, I don't have an FCC ID number on my transmitter. I have them on my others but not this one.

What's that about?

Lynx 02-16-2003 07:46 AM

Question about Futaba 9c 50 mhz output.
 
It may not be required with the 50Mhz module? Dunno. BTW, just to give you an idea. 700MW's transmitters (should) drain about 145ma of juice. Just to compare 1 watt is only 208ma. Xmitter power does not significantly effect battery drain. Unless it's tuned wrong, then you'll lose power in harmonics and heat.

KG4MIN 02-16-2003 12:05 PM

Question about Futaba 9c 50 mhz output.
 
Here's the answer to the questions about what license is required to repair and operate your transmitter. I hold both Ham and Commercial Radio Telephone licenses and neither is required to repair your equipment. You do need a valid Ham license to operate on 50 megahertz (notice the word operate). No license is required for 72 & 75 Mhz. I know there are people who just can't belive this but the following has been copied and pasted from the FCC website for you.

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.

Pay close attention to the statement directly above.

For those that still have problems with this go here:

http://wireless.fcc.gov/commoperators/wncol.html

Now having said this, I wish for you to keep in mind there are requirements to be maintained even though no license is required you can still violate regulations.

For example, you wish to change a transmitter to another channel. Simply replace the crystal with one for the new channel and check the transmitter with both a spectrum analyzer and power output device. Now your set. Don't have these items? Well maybe that's why most people believe licensing and radio shops are required. Not so.

amcross 02-16-2003 12:09 PM

Question about Futaba 9c 50 mhz output.
 
KG,

<<For example, you wish to change a transmitter to another channel. Simply replace the crystal with one for the new channel and check the transmitter with both a spectrum analyzer and power output device. Now your set. Don't have these items? Well maybe that's why most people believe licensing and radio shops are required. Not so.>>

Respectfully, on this one you are mistaken.

Your quote is 100% accurate. anyone can repair and maintain their own equipment. HOWEVER modifying the transmission equipment in any manner is against FCC regulation, including hcanging frequency by changing crystal.

KG4MIN 02-16-2003 01:49 PM

Did you ever see this before?
 
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.

Off the Futaba Website:

What proper license is Futaba talking about here?

Accessible to the user? Has Futaba ever made the crystal accessible to the user?

Just to clear up this subject, if I can't change a crystal, neither can Futaba and they offer to do this. I really think one needs to consider what is a modification. I believe the FCC, Futaba, and Myself don't consider changing a crystal a modification. After all there was only one type acceptance, not one for each radio on each channel.

Please reread my first post. I did state the radio still has to be checked, but I guess I failed to state retuning may be required. Here again this requires no license, although in Part 95 the FCC does suggest someone who is qualified should do this.

So let's see: Am I being monitored by the FCC and Futaba is not?

amcross 02-16-2003 02:52 PM

Question about Futaba 9c 50 mhz output.
 
First, please remember, I'm not affiliated with Futaba in any manner any more. Next, please know i'm not trying to be argumentative. Believe me, i spent WAYYYY too much time working with this stuff when i was still at Futaba. This will be my last post on the topic, and please don't take that as 'blowing you off', but this hobby is supposed to be for fun now, and arguing semantics over regulations just isn't my idea of fun. :-)

"(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. "

Crystals in the US are secured in a holder, covered with a cap, or glued in place as required by FCC.

FCC most clearly states right here that yes, changing a crystal IS a change and is not allowed.

The US Futaba service center has a certification for radio service, including modification, which IS from the FCC and which is "policed" by the FCC. do I recall the type of certification, or even am I sure which head technician holds the license specifically? sorry, no.

Damnathius 02-16-2003 03:14 PM

Question about Futaba 9c 50 mhz output.
 
KG, you quoted, and I quote:

"You do NOT need a commercial radio operator license to operate, repair, or maintain any of the following types of stations:

...

Personal radio equipment used in the Citizens Band, Radio Control, and General Mobile radio services."

It states "Radio Control". Now, is this a "general" statement, or does it also include the 50 mhz band? I looked around the site under "Commercial Radio Operator License" and could find no reference to suggest that 50 mhz is not included in the above statement.

Damnathius 02-16-2003 03:20 PM

Question about Futaba 9c 50 mhz output.
 
Nevermind... I figured it out. I think... :)

Lynx 02-16-2003 08:32 PM

Question about Futaba 9c 50 mhz output.
 
It's a general statement.


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