lvjax

Being new to this R/C Hobby, I recently came into a JR CIRCUS Model D4C-4SN Radio , complete with all servos, Receiver, Batteries, Charger, etc. still in the Original box.
This is a 72 MHZ AM Radio.

Someone told me that this Radio is NO LONGER LEGAL to operate ! Is this true ???

I have no use for it and wanted to sell it, but I don't wish to sell something that is ILLEGAL to operate.

Does anyone know about this Radio ??

I want to get into R/C Electric Helicopters, but I guess this radio is not what I need.

Any comments or help will be greatly appreciated.

Anyone interested can contact me via e-mail:

[email protected]

Thanks

MO_Radio_Tech

Yes, the transmitter is "wide". The RF signal it produces splashes on channels next to it, including industrials between our RC channels. (RC shares the 72 mHz band with industrial cranes). Because it will interfere with adjacent channels, it is no longer FCC compliant. Horizon probably can not make it narrow anymore. Maybe some other radio shop could?

The receiver is also wide. It will be prone to interference from adjacent channels. I do not think it can be narrowed.

The radio system is inadequate to fly most helicopters.

You will need a 6 channel computer radio to fly most current helicopters. It would be best to buy a "heli version" transmitter as the switches and pots are optimized for Helicopters. Swash mix or "CCPM" capability is also a must for your transmitter.

lvjax

Mo:

Thanks for the HELPFUL information.

I guess if I can't sell it, it will hold down all these papers on my desk.

Thank you sir !

Oh yeah...one more thing...maybe two....

What does CCPM stand for and what does 3D stand for ?

I am trying to learn all this R/C Heli "Lingo" and reading as much as I can, but have not run across the meaning of those terms yet.

I am re-cuperating from Open-Heart surgery with alot of time on my hands and Electric Helicopters have caught my attention....

Lynx

CCPM means Cyclic Collective Pitch Mixing. The way a Helli's rotor is designed there is a mechanical multi ringed swash plate that attaches the servo to the main shaft. This is where the servo's apply force to control the pitch and cyclic of a heli. Because of the way the swash plate balances one servo can not be used to control one thing. A blending of all the servo's together creates the required swash plate movement to get the desired result. This is usually three servo's at 90 degrees to each other. Older Helli's used slightly more complex setups with more linkages to do the same thing, but almost all Helli's nowadays are electronic or mechanically mixed. Electronically the radio does the calculations to turn you moving the stick into swash plate movement. The servo's can be drive directly one for each function and the CCPM is done mechanically. It generally makes for a better interface between the servo's and the mechanics than the older style linkages less to go wrong. The biggest thing is if you get a CCPM Helli to make sure you have a radio that supports CCPM.
3D is widely argued =) It generally means extreme maneuvers done with an aircraft that push (or exceed) the flight envelope for the craft.
Check out http://www.augustoheli.com/videos/video archive/default.asp

Has some awesome movies of 3D that will blow your mind. I've seen some video's in there of people doing chaos launches with fast piro's and it makes you wonder if the laws of physics were broken.