Txmtr vs. Recvr compatibility?
 

I have an Airtronics transmitter & receiver on Channel 22. This combination works fine.

But when it came time to build a 2nd plane, I thought I'd try a Tower Hobbies receiver (Channel 22), and I have two old Futaba servos which seem to have the correct plugs.

This combination does not work at all. Does my problem lie in mixing Airtronics transmitter signals with a Futaba servo? Or do I need an Airtronics receiver?

As you can see, I'm out of my depth. How much compatibility is there to all these different brands??

Thanks for any advice!!

Charles.

RE: Txmtr vs. Recvr compatibility?
 

The Tower rx is essentially a Futaba 127DF rx which responds to a negative shift FM signal from the tx. In the USA Futaba (and Hitec) tx's generate a FM (PPM) signal which is a negative shift, whereas Airtronics (and JR) tx's utilize a positive shift. Your Airtronics tx cannot communicate with the Tower rx because of this shift difference. In addition to an Airtronics rx, you could use an aftermarket rx made by Hitec for Airtronics or an FMA rx made for Airtronics.

RE: Txmtr vs. Recvr compatibility?
 

Which Airtronics RX do you have? The RD6000/8000 series let you select which "shift" you transmit.

RE: Txmtr vs. Recvr compatibility?
 

Ahh, then that explains my problem. I'd heard of shift, but didn't know the implications.

My Airtronics is an older model, from the early 90's, but in great condition.

What advice do you guys have for me? Shall I buy receivers that match my old Airtronics transmitter? Or just buy a new Futaba or JR or something and standardize on that? So far I just have the one old trainer, and this second one I'm working on. Now would be the time to jump ship if it makes sense.

Thanks!

RE: Txmtr vs. Recvr compatibility?
 

There are several things I would consider in a situation like this. Do I need more features that my old transmitter will provide ? more channels, computer functions for more versatility ? or do I just need to set up another airplane. An aftermarket receiver could be had for 50-60 dollar range (HItec or FMA; by the way, Servo City is a good source for Hitec..good prices and no shipping charges).
A previously used Airtronics 6 channel FM receiver might be found here on RCU..put it in the "WANTED".

If I chose to buy a new system, I would certainly consider the new Airtronics VG6000, a new entry-level 6 channel computer radio with super-simple programming. As the member who also responded mentioned the RD6000/RD8000 systems which will allow the transmitter to be switched to communicate with negative shift receivers; I would consider either of these. The October 2003 issue of Model Airplane News (M.A.N.) has an excellent review of the VG6000 and RD8000.
I have used Airtronics equipment since the mid-80's with excellent results; currently flying a Stylus as well as an Infinity 660. (By the way, I might have a good 92765 FM 6-channel rx for sale if you are interested...I have to take stock of what I have)