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I got out of RC cars briefly in about 1989, and re-entered the hobby in 1993. When I came back, I was told that I had to get a new radio because my old one was now "illegal" because it wasn't narrow-band. But later I heard there was a way to "retune" the old radios in order to make them compliant.

Fast-forward 20 years, and the majority of my runners are on 2.4. But I have a couple of cars that are all old-school electronics, and I like to run them with the old radio gear. Plus, they're 2-sticks, and I find myself gravitating back to that format as I get older. I have one 27mhz and two 75s. I assume that the 27mhz is OK because they're still on the same six channels they were back in the 70s. But what about the 75s? Should I not be using them? If not, is there a way, without returning a 25 year old radio to Futaba, to make them compliant with the narrow-band spec?

There is a easier solution. If you can solder You can get a 2.4 hack module from hobbyking. It has a simple 3 wire installation. I bet that it is far less than sending it back to get retuned. Really these days I do not think people really care. I still use crystal based products that I race. Most of the time I am the only one at the track that has not converted.

Technically crystal radios still have a better range. I'd only use FM or PCM though.

urban hype wrote:There is a easier solution. If you can solder You can get a 2.4 hack module from hobbyking. It has a simple 3 wire installation. I bet that it is far less than sending it back to get retuned. Really these days I do not think people really care. I still use crystal based products that I race. Most of the time I am the only one at the track that has not converted.

Me too- even better, I still use my 1991 Futaba PCM at the track Never a problem

I have heard a lot of talk in the airplane community about how much better pcm is than 2.4. Especially if it is installed in a model with a lot of carbon. I personally have had some severe issues with Spektrum gear in the early days, and even with my newer stuff I occasionally get inexplicable glitching. In short, I don't really trust 2.4 completely. I use it in my cars, but still fly with pcm or ppm.

Guys, I'm talking about pre-1991 entry-level AM radios. I just like how they look and feel, and I want to know if I can still legally use them.

markbt73 wrote:Guys, I'm talking about pre-1991 entry-level AM radios. I just like how they look and feel, and I want to know if I can still legally use them.

LOL, your title is misleading.
Legally


#1 why would it matter to the FCC
#2. As far as I'm aware, once the assign a frequency, it stays.
#3. AM stuff still sucks, just more than it did pre-91'.

Just use with caution, as they're prone to unreliability.

As for wide band transmitters it depends on what frequency it uses (27mhz, 72mhz, or 75mhz) here's a link to the futaba website that talks more about it, on the left side it's the fifth bulliten down. This page explains wide/narrow band and older radio equipment pretty good. If I remember right the old wide band stuff would interfere with pacemakers, this page will explain all of that though, I might be remembering wrong

http://www.futaba-rc.com/faq/service-faq.html

Narrow Banding also only applies to new build or licensing. Since your device is already made and you have no licensing to renew with the FCC, it doesn't matter at all.

On the other hand, the transmitters my company makes all have to be narrow band if new. If a customer is re-licensing their FCC stuff, they are required to be narrow band compliant. So they have to replace their hardware, we don't bother with retuning.

And none of it truly has to do with interference. It's more to shore up the spectrum and allow the FCC to sell more licensing. Why a quasi governmental organization feels the need to drive more revenue is the bigger question.

markbt73 wrote:Guys, I'm talking about pre-1991 entry-level AM radios. I just like how they look and feel, and I want to know if I can still legally use them.

To be honest even if it was one of the small number of pre-91 radios that are illegal, you are unlikely to come across someone scanning frequencies to check the legality of your radio. If you aren't operating on a frequency near to other radios then a wide band radio is unlikely to interfere, and with everyone today thinking 2.4Ghz is best it leaves the other frequencies clear for those of us happy to use crystal radios. Just remember the old wide band radios put out 500mW of power, 1991 and newer radios are limited to 100mW power so you can easily swamp any signals from radios operating on nearby frequencies.

Another one here still happily using a Futaba FF3, with PCM for the more serious cars. At one race meeting I had the aerial be snapped off at the case in an accident, and ran the whole meeting with no interference. I only noticed when I got back home I had been racing with a 1/2 inch long receiver aerial.

I'm pretty sure aslong as your not using 40 band or 72 band your good to go atleast up here in canada anyway