Synthesized means that it does not have a crystal (per-se) in the receiver and that it can "synthesize" or create any frequency in the band. Some call it "dial-a-crash" and those transmitter/receiver combinations are not that popular. The reason they are called that because you can select an operating frequency, one that is apparently vacant at your flying field, and then forget about it. Someone could come along with your frequency, and if you didn't take the time to pull your frequency off of the frequency board, well, when that person turns on the transmitter, well, you crash. Also, you could forget about your frequency, and leave. The next time you show up, you accidentally turn your transmitter on, forgetting that it is on that frequency, and someone else crashes. Lots of possible scenarios for this. Again, it's a nice idea, but not very popular. I had one for a short time, had trouble with it.. every other model memory channel caused servo chatter.. so I sold it.

With regard to RC receivers, “dual conversion” is a technique in which the receiver operates at two lesser frequencies besides the operating frequency. The basic dual-conversion receiver employs two crystals rather than one. Because of the “extra” level of conversion, these receivers can be made more selective and more immune to certain interference situations.

The basic dual-conversion receiver will, by nature, be slightly larger in size, weigh a little more, and be slightly more expensive than a single-conversion receiver. There is nothing wrong with single conversion, and several lines of RC receivers have used that type of circuitry successfully for many years. However, most receiver labels these days will identify the product as “dual conversion.”

This one is a bit less technical so I deleted the last one and put this one in instead. It still is a tad bit technical, but all this means that it is not as subject to inteference than single conversion receivers are.

CGr.