Hi everyone.
I have a Futaba 72 Mhz Dual Conversion Rx that had the stock crystal for channel 45 ( 72.690 Mhz ) .
I need to change the crystal to channel 46 , so can i just swap the crystals ? or does the RX need to be re-tuned or something ?
Also Dual conversion Rx are in Hi and Lo band , within the 72 Mhz range . What is that for ? Since my both crystals are in the HI range, then i should be able to swap the crystals without retuning ?

Let me know your thoughts on this.
-Gaurav

With Futaba, as long as you are sticking with the same conversion (single or dual) AND the same band (lo or high), then you can change crystals without any other changes needed.

So 45 to 46 should be just a crystal change, as long as you pick the same conversion type.  The single conversion crystals (Futaba brand itself) have a black covering, while the dual conversion ones come with a red covering.

Ok, just curious. I understand the single and double conversion deal ( they relate to how the signal is filtered ) .
But what does the Hi/Lo band mean ? i mean if we are on the same frequency range 72 Mhz, how does the HI band or Lo band fit in, and its importance ?

I think the whole conversion thing is over-rated.  Case in point, JR has always been single conversion, and they are not considered inferior in any way (including range of reception).

The lo band receivers are tuned for better reception in the low frequency ranges (channels 11 through 35), and the high band ones are tuned for reception in the higher frequency bands (above 35).  So if you are changing crystals, you have to pick one in the same band.

This is done currently by Futaba only, so they can have better reception performance. The other manufacturers leave the tuning around the middle so that they can accept any frequency (ie, any channel from 11 to 60).