rcagpilot83

Years ago I had bought a plane that had an old old futaba radio, or at least I think it was a futaba. The transmitter was all gold anodized aluminum. I don't have it any more but it came up in a discussion that I had with a buddy of mine. Looking at a channel and frequency chart on futabas website am runs on 27 or 50 mhz and fm runs on 72 or 75 mhz. What about old plane radios cause I could of swore that mine was channel 40 which is a channel # for a fm frequency. They also said that 75mhz fm is not for use with aircraft and they say the same for 27mhz am. So I'm trying to find out what my radio was.

jay2000dakota

Maybe it was a Kraft radio, My dad had 2 Kraft Am's that he used until the late 90's when Am was outlawed at our field. I know that cases were gold but I can't remember the fequinecy.

BillyGoat

I had one of those. It's the Futaba FG Series. AM was used on 72mHz. Everyone went FM becasue I guess it had less noise/interference. At one time I had both FM and AM (gold sitckered) radios and didn't notice any more reliablity with FM.

Since Futaba no longer sells AM radios on 72 mHz, the information your looking up is what is available from Futaba today.

BillyGoat

AM was not outlawed. Here in the US, and I'm assuming the same thing happened in Canada, what happened is the R/C spectrum was rearranged to allow for many more frequencies. When that happened many older radios became obsolete because they were broadcasting on a wider band than was allowed. It’s the wider band radios that were 'outlawed' and they just happened to be AM. Manufactures like Futaba did make AM narrow band radios but at the time FM was becoming very popular. AM can still be used today as long as it's narrow banded.

carrellh

He did write "at our field" so maybe it was.

The Futaba FAQs have info about how to tell if a Futaba AM transmitter is narrow band
http://www.futaba-rc.com/faq/service-faq.html#q41

ho2zoo

My Feedback: (5)

I have three older Futaba AM radios that still work fine. They use the 72 mHz band for airplanes just like the FM radios do. They have been upgraded to 'narrow band' and so are 'legal' for use in the U.S. Some clubs may restrict their use at their local fields, though. Futaba still makes and sells AM radios:

http://www3.towerhobbies.com/cgi-bin...=LXCTD2**&P=SM

BillyGoat

True!


Looks like I stand corrected twice. Never really considered a two channel radio an "aircraft" radio, but they do say it's 72 mHz. Although I have a problem with Tower saying it's ideal for cars and boats. Those are to be operated on 27 mHz.

Square Nozzle

My Feedback: (1)

[quote]ORIGINAL: BillyGoat


Looks like I stand corrected twice. Never really considered a two channel radio an ''aircraft'' radio, but they do say it's 72 mHz. Although I have a problem with Tower saying it's ideal for cars and boats. Those are to be operated on 27 mHz.


Futaba is saying that because 72 mHz is for aircraft only. 27 and 75 are for surface vehicle use. 27 can also be used in aircraft but is more prone to interference.

BillyGoat

John, did you read the very first two sentences of the "Notes from the Tech deptartment" in that link?

"This is the 2ER, 2-Channel, Digital Proportional 72MHz AM 2-stick Radio. Ideal for entry-level cars, boats and airplanes."

Even if they offer it in 27 and 75 mHz they need to redo those sentences becasue the "entry-level" modeler just might interpert that as 72mHz works for all.

Square Nozzle

My Feedback: (1)

No I didn't read the actual Futaba wording. I only took what was in the posting. You are absolutely correct. Futaba is incorrect and misleading in stating that a 72mHz AM radio is ideal for "cars, boats and airplanes", entry level or not. 72 is not legal for use on surface vehicles (cars and boats).

ho2zoo

My Feedback: (5)

The Tower link is indeed somewhat confusing. Further down on the page they do state that the 75 mHz band is for cars and boats. My only point was to show that AM radios are still being produced and used. I have used this particular radio for sailplanes and small .049-powered planes.

JollyPopper

My Feedback: (6)

Several years ago, just a couple months after I joined RCU, somebody wrote a loooooooooooong acticle about the relative merits of AM radio vs FM radio. He may have been totally full of it, but he sounded very knowledgeable, and AM radios came off looking very good. If I am not mistaken, I printed that article and put in in a three ring binder that I keep for articles I take off the net concerning RC stuff. I think I will look next time I go out to the shop and see if I can find the article. He really made AM radios sound better in many cases than FM. I have two or three old AM radios, narrow banded, and use them occasionally, but mostly I have FM. I can't tell the difference in use. Currently, I am slowly changing over to 2.4 stuff and now have four 2.4 receivers. Can't tell the difference in those as compared to AM or FM either.

I-fly-any-and-all

My Feedback: (1)

if it is gold stickered it is safe to fly if it is silver stickered it will broadcast on 5 channels beneath and above itself.

carrellh

One of our club members has a Futaba AM system in a combat Gremlin. He has been flying RC for about 30 years and he said the only radio he has used without EVER getting a glitch of any kind is that AM sytstem.

That doesn't mean it will be trouble free on the next flight but it does have a pretty good track record for him.

red head

I still have a couple AM radios that I use now and then. When I do I pin 3 channels either side of my channel. I don't use them often but don't have any problems. ENJOY !!! RED

red head

SORRY, I ment I pin 3 channels, one on each side of my channel. ENJOY !!! RED

motorist2

I and others who fly old spark ignition engines in our OT SAM type airplanes experienced more ignition interference when we started switching from AM to FM. But that was some years ago. Lately the newer FM's have improved to about the same level of reliability that we still expect from our narrow banded AM's. I still fly both AM and FM with reliable performance. But I'm also using some 2.4GHz, which is a real improvement over both AM and regular 72 MHz FM as far as supressing ignition interference.
Motorist 2

HighPlains

My Feedback: (1)

FM radios were cheaper to build than AM radios. That is the real reason that RC systems went to FM.