DENNIS C

My Feedback: (99)

hey danny is the 549 & 649 singal or dual conversion if not which one are.

thanks dennis

dsnyder

Both of those receivers are single conversion. The only receivers that are dual conversion from JR are the 940 and 945.

DENNIS C

My Feedback: (99)

thanks danny can you tell me what the difference is in the singal conversion & dual conversion. and why would someone use a dual conversion.

thanks again

dsnyder

In single conversion the signal is filtered once while in dual conversion it is filtered twice. This makes the mirror image frequency, the second frequency that the receiver uses, different between the 2. With single conversion, the mirror image frequency for aircraft is 450 mhz above the frequency of the crystal. In dual conversion it is 910 mhz above. So if there is any noise at the mirror image frequency of single conversion, the dual conversion would correct the problem or vice versa. With JR's abc&w system, dual conversion is not needed, as the receiver uses a filtering process that better reduces the chance of interference. The dual conversion also uses 2 filters, which the filter and the crystal are the most common points of failure of a receiver due to vibration etc. However we offer the 945 receiver on dual conversion for those models that may require it due to noise problems.