Can you still fly FM frequencies?
12-10-2017, 10:14 AM
#1
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Location: Waynesboro, GA, USA
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Can you still fly FM frequencies?
I have an old Hitec Prism 7 that I would like to use. I have been out of the hobby for many years. Can I still fly with an FM 72 mhz frequency radio?
12-15-2017, 07:48 PM
#4
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OK, how about a 72mhz "AM" system? I recently got, via Ebay, a NIB WattAge Thermalaire 72" electric powered glider complete with a Hitec 3ch AM 72mhz TX and RX, and ESC. All new in the original box, never assembled or used. BTY, it was cheap! 
So, just for giggles I put batteries in the TX, installed a suitable RX battery in the fuselage and what do you know.....It works! The ESC operates the preinstalled electric motor, and the 2 servos (rudder and elevator) both work as intended. Oh course it works, it's new, well sorta new in a 1980's way. I had planed to fly this motor glider on one of my surplus Futaba 72mhz FM systems. I also have Spektrum and Tactic 2.4 radios but didn't want to "waste" a 2.4 RX on this plane. But now, for adventure I want to try flying this glider on the original 72 mhz AM Hitec system. Am I legal or am I going to Jail ?
So, just for giggles I put batteries in the TX, installed a suitable RX battery in the fuselage and what do you know.....It works! The ESC operates the preinstalled electric motor, and the 2 servos (rudder and elevator) both work as intended. Oh course it works, it's new, well sorta new in a 1980's way. I had planed to fly this motor glider on one of my surplus Futaba 72mhz FM systems. I also have Spektrum and Tactic 2.4 radios but didn't want to "waste" a 2.4 RX on this plane. But now, for adventure I want to try flying this glider on the original 72 mhz AM Hitec system. Am I legal or am I going to Jail ?
12-16-2017, 05:58 AM
#6
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Location: Lyndonville, VT
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Larry,
You still can use AM on the 72 mHz band. The question is whether the transmitter is narrow band and if the frequency is one of the current 52 channels that are legal for RC use.
what frequency and channel is the radio on?
i wouldn't worry too much about jail though
Pete
You still can use AM on the 72 mHz band. The question is whether the transmitter is narrow band and if the frequency is one of the current 52 channels that are legal for RC use.
what frequency and channel is the radio on?
i wouldn't worry too much about jail though
Pete
12-16-2017, 08:31 AM
#7
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The Hitec AM TX is on ch 26 (72.310). I know it makes no practical sense to use the 30 yr old radio system but my crazy side wants to try it. I didn't start flying RC until late 2001 so I missed that era of RC. I only paid $45 for the plane/radio and shipping so I can roll the dice without much financial worry. I will give it a good range check before launching the glider as a final test when I'am ready. Thanks to "hockey" and "pete" for your input.........I wonder if I should play some "disco music" when I fly it !
12-28-2017, 08:45 AM
#10
Yes, yes of course you can as the fellows have already indicated. The Prism 7X are all post 1991 and most certainly completely compliant with FCC reg. And that is using either the single fixed frequency module or the selectable frequency FM modules.
I still own three of them purchased new back in the mid nineties. Those three are not just relegated to self life now though, The Prisms I not use for controline flying with case modifications to hang the radio around my neck but to lie flat on my chest with the sticks pointing away to the airplane.
On the subject of nostalgia use of certain very old radios with much help from a few very knowledgeable technical types I was finally able to start using my 47 year old treasure. I purchased this Orbit Six in 1970 from Brookhurst hobbies, fullerton Ca. and actively used it until 1991. From that point on being very wide band and on a no longer legal frequeny I had to park the radio as very illegal. This deep sleep lasted for thirty years and I never discarded the radio. Thanks to my friends mentioned above now I can use this radio agine converted to 2.4 and a Hitec module at that Completely legal once agine and to that end built a period correct airplane to fly with it, a 1965 Aristo Cat.
John
01-06-2018, 01:23 PM
#12
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I use my Hitec Eclipse 7 FM for my gliders.
It is unfortunate that some clubs no longer allow 72Mhz/FM radios on their sites. That there has been a number of documented problems with 2.4 radios of certain brands and their failures, yet at certain clubs, 72 Mhz has been banned.
It is unfortunate that some clubs no longer allow 72Mhz/FM radios on their sites. That there has been a number of documented problems with 2.4 radios of certain brands and their failures, yet at certain clubs, 72 Mhz has been banned.
01-14-2018, 08:54 PM
#13
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Ive always understood that if the FCC approved a transmitter for use and sold in stream of commerce that it can never become illegal to operate. The AMA however chooses to deny coverage of transmitters they deem necessary. This is the confusion you will likely encounter depending on who your talking to on the subject. .02
01-15-2018, 10:13 AM
#15
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The Federal Communication Commission is the US based agency that approves any device that transmits a signal. All the radios we buy for our toys went thru an approval process thru this agancy so they can be sold in stream of commerce. Thus why they are technically ALWAYS LEGAL. The AMA however choses what radio tramitters they care to include in their insurance coverage. They do not cover wide band 52mhz 53mhz 72mhz operation as they feel it poses a greater risk for a claim.
Now just google Hobby King selling illegal transmitters if you really want some in depth knowledge of this approval process.
Now just google Hobby King selling illegal transmitters if you really want some in depth knowledge of this approval process.
01-15-2018, 10:49 AM
#17
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I think your missing the point, Why dont you take a picture of your transmiiter specs showing its a NARROW BAND. I been in the hobby 45 years and it is common knowledge the AMA no longer covers WIDE BAND transmitters, Narrow Band ARE covered. I still have wide band JR modules for my JR stuff I of course no longer use them but kept them.
Wide Band TX were first needing a 50mhz spread beteeen adjacent chennels. then they Narrowed it to 10mhz between adjacent channels thus the term NARROW BAND.
Wide Band TX were first needing a 50mhz spread beteeen adjacent chennels. then they Narrowed it to 10mhz between adjacent channels thus the term NARROW BAND.
01-16-2018, 10:12 AM
#19
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Heres the exact confusion posted above, as I said depends on who you ask.
WIDE BAND transmitters that were once legal and sold as legal, are not illegal to operate according to FCC law.
In 1991 the AMA who is just an insurance company chose to not cover customers using wide band transmitters in favor of narrow band.
Now its more likely you might be illegal using a 2.4ghz Hobby King Transmitter that never recieved FCC approval. 😊 I wonder what AMA will do with that claim.
WIDE BAND transmitters that were once legal and sold as legal, are not illegal to operate according to FCC law.
In 1991 the AMA who is just an insurance company chose to not cover customers using wide band transmitters in favor of narrow band.
Now its more likely you might be illegal using a 2.4ghz Hobby King Transmitter that never recieved FCC approval. 😊 I wonder what AMA will do with that claim.
01-16-2018, 12:40 PM
#20
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01-20-2018, 11:11 PM
#21
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It was not the AMA that disallows wife-band systems. In the late 1980’s, the FCC created a host of new frequencies on the 72/75 MHz band the regulation had s phase-in that opened some of the channels while keeping the old ones. Then the old ones were made illegal and the rest were allowed to be used. The regulation had a date after which only narrow-band equipment could be marketed. After March 1991, equipment that did not conform to the narrow-band specification was no longer allowed to be used.
I know this because I was charged with the task of taking my then-company’s RC system through the Type Acceptance process. A search of old AMA articles will also show the dates and phase-in schedule.
I know this because I was charged with the task of taking my then-company’s RC system through the Type Acceptance process. A search of old AMA articles will also show the dates and phase-in schedule.
