knight1

I have five planes but all on different freq.
What I want is my 9z tx for all.
Here is the question.
I understand for changing frequencies on tx's you must send in your radio
to have the radio properly tuned for a specific channel which is a real good idea
considering you'll have optimum range among other issuses for that frequency.

? 1. Do you have to send in the tx and or rx if the channel is within the current high or low band.
(ex. channel 37 changed to 40)?

? 2. With the recievers, would they also have to be sent in? (I would think they would have to be
but never heard anyone talk about
sending in the rx's just the tx's)

? 3. The 9Z tx has different modules available, would that have to be sent in as well?

Thanks in advanced for the help.

nilo

I have a JR X378 TX. I really DO NOT believe that the reason from the need of sending the TX to a legal service to change the crystal is related to any tunning to be done for optimal performance.
These RX uses IF (intermediate frequency) detection based on the chystal frequency, that means the Chystal frequency(local oscilator) interacts with the desired "on the air" frequency creating a seconday frequency, the IF. The IF is constant, what means there is no tune to be done in the RX. The "On the air" frequency is the one transmitted by the TX. The TX range of frequencies is very narrow band. For low 72Mhz band the start frequency is 72.010Mhz and high end at 72.49Mhz. He high 72Mhz band starts at 72.510Mhz and ends at 72.990Mhz.
I belive the performance wouldn't change if you use another channel. I think the real reason for sending your TX to change the Crystal is for someone having the control that you are changing it to something inside the allowed band. In this case, there's nothing to do other than send it to then.

Nilo

randy41

To change freq on futaba module series tx. All you have to do
is buy the module with the freq you want(Dont have to send in the
radio) to change freq.

You can change the crystal in the receivers to the same
freq of your radio with out sending tx or rx in. This will
allow you to run several models with on radio.

EX: Your radio is on channel 40. If all your receivers are high band
than just change the crystals to channel 40 in all your receivers.
Its ok to change the crystal in a receiver if you keep it in the
high or low range.

knight1

Thanks randy41, just exactly what I hoping to hear.
that makes it a lot easier.

DBCherry

My Feedback: (4)

Randy's right. With the higher end transmitters, all you have to do is change the module. All the "tuning" is in the module.
Rx crystal can be changed among high (or low) band channels.Dennis-