Why 2.4ghz over 72mhz fm?

[bhursey]

Possibly im old school or just don't get the extra benefits of 2.4ghz. It seems from a basic point there is no real reason for me to upgrade. I will list the known limitations that I know of however I am not really sure what else there is that would really motivate me to switch..

Limits I know of: Most are not a big deal
1. No more worrying about conflicting with channels *This is not a big deal anymore I have found out at clubs i have visited no one flys 72mhz. Im kinda in an exclusive club*
2. No more long antenna. "not really worried about that I like the antenna to tell the wind direction."
3. Not able to use BNF with horizon equipment. "This is one of the ones I am iffie about. This is one of the reasons I may get a 2.4 module for specific circumstances"
4. Fly ins require 2.4 "Yah again a reason I may get a module just for flyins"
5. Antennas longer.

Benefits of FM:
1. Longer range easy 1-2 miles "bonus for fpv"
2. Analog so signal slowly goes out instead of cuts off
3. No need to worry about directional and satellite antennas. FM does not care
4. Cheep radios on ebay if you want another one
5. Built in wind direction tool. AKA the streamer.
6. My radio does most or all what modern radios do I have a High quality Futaba T6XA Super just orderd a second one for my daughter to buddy box.


Anything I am missing? I just don't see a reason to dump FM at the current state of the hobby now that I am one of the only ones. I may install a 2.4 module with a switch to swap protocols in a year or so i can fly in certain situations. However I still think the majority of the time I will be using FM.. Just wondering thoughts on why its necessary to swap.

 

[mjcp]

In the US, RC use of 72Mhz is a secondary user status, you don't get first dibs on it...

2.4ghz kit has been designed from the ground up to hop between other users...


Couple of thoughts of the top of my head..

mjcp

 

[pressalltheknobs]

guessing here but sophistication of the receivers... Telemetry and programmable failsafe in particular. Maybe model memory, ppm/sbus support. While these things or things like them may have been available for 72Mhz they were probably new and high end so likely a bit rough around the edges and not widely used or supported.

Also, you are dealing with old stuff and it will start to break down due to age. Happens to us all.

However, you covered most of the reasons, crowding and inconvenience being the main one, and they don't matter to you so if you are happy with what you got, just keep on trucking.

 

[Cereal_Killer]

A BIG plus for 2.4 is the ability to assign a "fixed ID" (pretty much equivalent to using a different xtals on 72mhs) for EACH of your models, that way you cant possible fly the wrong plane on the wrong model file and flip a switch that should be (random example here) your landing gear and instead it goes full up elevator or something if you had the wrong model selected. Even if you're using the SAME EXACT brand / type / model number of receiver in two different planes, you could literally turn them both on and the tx would only control the one who's model is selected, the other model would sit still without a radio link.


Another advantage is that if you're flying long range and your model flies into an area with a dirty RF environment on 72 there's NOTHING that can be done about it, you just have to hope you can turn around. With 2.4 the radio (tx and rx) will simply stop using that particular frequency (unless you're using the old FlySky protocol or DSM2, however DSMX and any other real FHSS will adjust their frequency hopping to stop trying that channel)

 

[bhursey]

A BIG plus for 2.4 is the ability to assign a "fixed ID" (pretty much equivalent to using a different xtals on 72mhs) for EACH of your models, that way you cant possible fly the wrong plane on the wrong model file and flip a switch that should be (random example here) your landing gear and instead it goes full up elevator or something if you had the wrong model selected. Even if you're using the SAME EXACT brand / type / model number of receiver in two different planes, you could literally turn them both on and the tx would only control the one who's model is selected, the other model would sit still without a radio link.


Another advantage is that if you're flying long range and your model flies into an area with a dirty RF environment on 72 there's NOTHING that can be done about it, you just have to hope you can turn around. With 2.4 the radio (tx and rx) will simply stop using that particular frequency (unless you're using the old FlySky protocol or DSM2, however DSMX and any other real FHSS will adjust their frequency hopping to stop trying that channel)

Failsafe is one of the things that would be nice you can set it up with PCM mode but you need to use a PCM reciver which i dont think i have. With PPM its just a throttle fail safe... As for frequency hopping thats cool and a bonis. I only had one issue with fm when a club member turned on his radio on the same channel i had in like 2000. Luckly he heard me yelling and turned it off and i pulled out. Frequency hoping is a bonis. Im thinking of adding the folowing modules one to each tx i now have 2 Futaba T6XAs. This one http://www.hobbyking.com/mobile/viewproduct.asp?idproduct=17205 and this one http://hobbyking.com/mobile/viewproduct.asp?idproduct=40205

 

[pressalltheknobs]

Failsafe is one of the things that would be nice you can set it up with PCM mode but you need to use a PCM reciver which i dont think i have. With PPM its just a throttle fail safe... As for frequency hopping thats cool and a bonis. I only had one issue with fm when a club member turned on his radio on the same channel i had in like 2000. Luckly he heard me yelling and turned it off and i pulled out. Frequency hoping is a bonis. Im thinking of adding the folowing modules one to each tx i now have 2 Futaba T6XAs. This one http://www.hobbyking.com/mobile/viewproduct.asp?idproduct=17205 and this one http://hobbyking.com/mobile/viewproduct.asp?idproduct=40205

For FrSky stuff I like to use Aloft Hobbies - https://alofthobbies.com/frsky-dht-diy-telemetry-module.html.

 

[razor02097]

FM is old technology. People move on. There is no specific reason to upgrade unless your existing equipment breaks or maybe you need more channels or the features of newer computer radios. As far as range goes... unless you are flying long range pretty much any good 2.4 system will give you all the range you would need for LOS flying. If you do fly long range...it would be better IMO to just bite the bullet and get a HAM license and an LRS. The last thing you want is to lose your model as your 72Mhz receiver glitches continually due to no failsafe.

There are so many options out there. If you want to upgrade to a 2.4 system FrSky has their DIY kit. You could do the mod David did in their video where he can turn the 72 system on and off. That way you get the best of both worlds.

 

[Spastickitten]

I could just imagine a mini with a meter long antenna poking out the top, so I guess the shorter receiver antennas are a plus for those who fly smaller airplanes. I understand what you mean on the idea, I just had a lockout on my plane recently, and I wonder how 72 megahertz equipment would have handled it.

 

[bhursey]

FM is old technology. People move on. There is no specific reason to upgrade unless your existing equipment breaks or maybe you need more channels or the features of newer computer radios. As far as range goes... unless you are flying long range pretty much any good 2.4 system will give you all the range you would need for LOS flying. If you do fly long range...it would be better IMO to just bite the bullet and get a HAM license and an LRS. The last thing you want is to lose your model as your 72Mhz receiver glitches continually due to no failsafe.

There are so many options out there. If you want to upgrade to a 2.4 system FrSky has their DIY kit. You could do the mod David did in their video where he can turn the 72 system on and off. That way you get the best of both worlds.

Yah i saw davids setup that is what i want to do for both TX's posibly but my wife kinda put a $ stop on rc stuff. Mostly i will fly 72 though.. A guy in our local fb groups going to give me his fm recivers. 2x4 channel at one 6 channel. I have 2x 6 channel. So thos would be tge first time i have ever got to use model memory really as its desinged because normaly I swap rx's. I flew for 6 years during those days on 72 in high school and beginning of college 4 of which were on AM. I never lost a model to rx issues.. If noticed in the ft videos some times they hit brown outs it kinda make me raise an eyebrow to 2.4. 72 if you had good radio managment at clubs were rock solid. As for fpv most of the time it will be LOS. My computer radio has plenty of features all that i need for now. One day if i want advanced head tracking a may get a 9x. So like ypu said if it works no need to replace. I guess im always old school lol. I used AM when FM was the main. now I use FM when every one uses 2.4. What was intresting my friend i flew with in high school a bit younger still flys with FM i asked him if he was gonna upgrade he said hell no. LOL.

 

[razor02097]

I could just imagine a mini with a meter long antenna poking out the top, so I guess the shorter receiver antennas are a plus for those who fly smaller airplanes. I understand what you mean on the idea, I just had a lockout on my plane recently, and I wonder how 72 megahertz equipment would have handled it.

72 won't act like a 2.4 with interference since it is an analog system. If you have interference that stomps on your transmitter signal you completely lose control of your plane.Once you lose signal the servos kind of go "limp"... they stay in a position until random interference glitches them to a new position or if there is an outside force it is very likely to move the servo also.

 

[bhursey]

72 won't act like a 2.4 with interference since it is an analog system. If you have interference that stomps on your transmitter signal you completely lose control of your plane.Once you lose signal the servos kind of go "limp"... they stay in a position until random interference glitches them to a new position or if there is an outside force it is very likely to move the servo also.

razor02097. If it regains signal it will recover though. It is not just a switch that kills it.. Most of the time you notice 72 having issues before it all the way cuts off. In some cases you may have time to turn around before you lose control. I have had seen a member once have a problem. I belive there was an issue with the antenna on the RX severely shortened there signal. Either the wire had a invisible break in it or something. It started glitching, he immediately turned around and regained control.. I believe though 2.4ghz has a quicker recovery on total loss of signal on the rx.. 72mhz is also a more versatile frequency able to bend and penetrates objects better from what I have read on other forums. That is why you dont have to have things like satilight antennas. Besides my antenna is longer than my plane LOL

Did you ever get the joy of flying FM?

2.4 looks to have some positive benefits. It definitely is good to get a module it sounds like when flying at congested RF environments. I fly out side of the city so never ran into issues.

 

[razor02097]

razor02097. If it regains signal it will recover though. It is not just a switch that kills it.. Most of the time you notice 72 having issues before it all the way cuts off. In some cases you may have time to turn around before you lose control. I have had seen a member once have a problem. I belive there was an issue with the antenna on the RX severely shortened there signal. Either the wire had a invisible break in it or something. It started glitching, he immediately turned around and regained control.. I believe though 2.4ghz has a quicker recovery on total loss of signal on the rx.. 72mhz is also a more versatile frequency able to bend and penetrates objects better from what I have read on other forums. That is why you dont have to have things like satilight antennas. Besides my antenna is longer than my plane LOL

Did you ever get the joy of flying FM?

2.4 looks to have some positive benefits. It definitely is good to get a module it sounds like when flying at congested RF environments. I fly out side of the city so never ran into issues.

Yes and I still have my skysport 4. The best part of FM is there was no protocol so you could use just about any FM receiver on the market. Though as time marches on it will be much harder to find new FM equipment.

As with technology moving on I don't see myself using my FM system. The newer 2.4 receivers are so much easier to find and have a failsafe. Plus my old FM radio only has 4 channels and has no computer capability. I just find it worth the $15 to put a 2.4 receiver in a new model.

 

[bhursey]

Yes and I still have my skysport 4. The best part of FM is there was no protocol so you could use just about any FM receiver on the market. Though as time marches on it will be much harder to find new FM equipment.

As with technology moving on I don't see myself using my FM system. The newer 2.4 receivers are so much easier to find and have a failsafe. Plus my old FM radio only has 4 channels and has no computer capability. I just find it worth the $15 to put a 2.4 receiver in a new model.

Yah the skyport 4 is a very very did I say very basic TX.. Its designed for beginners. I would definitely not go back to that you can get plenty of better transmitters. I can clearly see why you got a new one. My TX is the Futaba T6XAs super its an advanced top of the line at the time TX. It has a ton of features.. It has smooth adjustable and high quality gambles also.

Here is the manual: http://manuals.hobbico.com/fut/6xas-hs-manual.pdf


This is the RX i last bought. Alex AKA IBcrazy got 5 miles on the 8 channel version. It is a synthesized rx so no need for crystals. It seems very stable. I am quite happy with it and its very light.. My other RX is the one that camer with the radio. Im about to get two from a local guy for free although they are lower quality GWS rx's so I am going to keep those in the cheaper, park flyer and light foam aircraft.

http://www.hobbyking.com/hobbyking/store/__6599__Corona_Synthesized_Receiver_6Ch_72Mhz_v2_.html

 

[HawkMan]

Actually the range you specify for FM is pretty much the standard 2.4 range as well. and with long range receiver like the FrSky L series receivers you'll be getting at least as long range as FM.

Also FM is just as directional as 2.4. the lower frequency makes it less susceptible, but it's rare to lose signals in digital signals because you only have one antenna and it's not in the same direction as the transmitter. it also transmits like a don, and you're defintiely not supposed to point an FM antenna towards the craft if you want to retain control it also has a theoretical difference between vertical and horizontal signal, but eh. it won't affect much, not at the ranges you fly planes anyway.

FM is ok. But, most of use who used to fly it have learned to love the new 2.4 gear after losing countless plain to inexplicable control loss from some kind of interference. That doesn't even take into account failsafe and telemetry, even just the simple signal strength return.

 

[bhursey]

Actually the range you specify for FM is pretty much the standard 2.4 range as well. and with long range receiver like the FrSky L series receivers you'll be getting at least as long range as FM.

Also FM is just as directional as 2.4. the lower frequency makes it less susceptible, but it's rare to lose signals in digital signals because you only have one antenna and it's not in the same direction as the transmitter. it also transmits like a don, and you're defintiely not supposed to point an FM antenna towards the craft if you want to retain control it also has a theoretical difference between vertical and horizontal signal, but eh. it won't affect much, not at the ranges you fly planes anyway.

FM is ok. But, most of use who used to fly it have learned to love the new 2.4 gear after losing countless plain to inexplicable control loss from some kind of interference. That doesn't even take into account failsafe and telemetry, even just the simple signal strength return.

Ahh yes i remember once seeing some one on the flying field back in the day hold his TX strgeht up and down and up high all the sudden. I would assume he was having issues. LOL..


My daughters sexcond TX for buddy box just arrived..

 

[HawkMan]

Why wouldn't Flyins allow 72Mhhz though? over here they don't care, there's so few using the they don't even bother with markers they just ask you to check with the other guy that you're not on the same frequency

 

[bhursey]

Why wouldn't Flyins allow 72Mhhz though? over here they don't care, there's so few using the they don't even bother with markers they just ask you to check with the other guy that you're not on the same frequency

I talked to one of my old club members who is in charge of registration at SEFF he said im fine using it but there is no impound. He said no one flys it anyways. Info tid bit My old club fayette flyers started SEFF. I was at the first one ever in 2003.

However at JoeNall they specifically state no 72mhz. :/

I always have tested the air with doing a quick test of turning on the aircraft on for a few sec. Note move your hand away from the prop. If the servos are making controlled movements then some one is flying within range. I know not that good of a method however just a short sanity check on uncontrolled areas.

 

[HawkMan]

Joe Nall is very big, so I guess they just say no to avoid the headache of having to manage 72Mh users. even if at an event that size it really shouldn't be an issue. but... one less headache among a thousand.

 

[bhursey]

Joe Nall is very big, so I guess they just say no to avoid the headache of having to manage 72Mh users. even if at an event that size it really shouldn't be an issue. but... one less headache among a thousand.

I truly doubt anyone would say anything to me since there is no impound..