It seems the sources for low cost 2.4GHZ hobby transmitters and receivers just keep coming out of the woodwork.
My latest acquisition was DSM2 compatible receivers called the “Orange Rx” from Hobby King.
http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=11972
The website states “NOTE* This is not a Spektrum receiver, nor is it a copy of a Spektrum Receiver.
The Spektrum brand is a trademark of Horizon Hobbies USA.”
It did take me 2 months to get them, as they were back ordered. But I finally got them, have bench tested them, and they work fine with both the RailBoss and the Spektrum transmitters (DX5E, DX6i).
You dont’ get any documentation from them, but it was easy enough to figure out. The pins are all labeled “Bat/Bind, Thro, Aile, Elev, Rudd” with a minus sign next to each one, indicating the pins by the labels are the negative (common) pins, and the pins on the other side of the board are the signal pins going to the control system. Of course I hooked them up backwards, couldn’t get it to bind, and then figured that out. No damage though!
Binding is done exactly like a Spektrum receiver using a binding plug on the battery pins.
The units I got are 4 channel Receivers. $13.99 each. They don’t have a case, but are shrink wrapped. 1.5" long x 0.5" wide, 1 inch antenna.
I see on the website, the 6 channel version with a hard plastic case is only $7.95.
Both of these receivers can be used with any Spektrum transmitter. The RailBoss can use either the 4 or 6 channel versions. The Beltrol the 6 channel.