Can I put a FUTL59** crystal set in my 75 MHZ 4EXA transmitter and R127DF receiver? I am a little confused due to the receiver is dual conversion and the tramsmitter is not and the crystals are one or the other. If not, what is the recommended crystal set for changing channels?

Thanks, Mitch

I was not aware that the 4EXA was available on the 75 mhz band. I thought it was 72 mhz only.

Transmitter crystals are neither dual nor single conversion; they are just transmitter crystals.

You cannot put a receiver crystal in a transmitter. Actually you can physically put it in but it will not work.

The part number you listed is not a “crystal set� it is just a receiver crystal. It has to be used in a dual conversion receiver.

The 75mhz FM crystal set is part number FUTL91** and it contains a transmitter crystal and a dual conversion receiver crystal. The set costs 24 bucks at Tower.
http://www2.towerhobbies.com/cgi-bin...I=LXH281**&P=7

Hi mahoo,

No, the 4EXA is sold only on 72Mhz (Air) you cannot use a 75Mhz (ground) crystal in the receiver and make it work. It will not recognize it.
Also you cannot change the crystals in your transmitter, this must be done by an authorized service center.
The FUTL59** that you are looking at is only a receiver crystal, it is not a set.
The dual conversion on your receiver refers to the the "second" or dual amount of filtering the receiver does with the signal, it does not refer to any ability to handle two different bands.

I hope you find this information helpful. You can also reach our Futaba support technical team at 217-398-8970, or via fax at 217-398-7721.

Sincerely,
Krysta Hunt
Lead Futaba Customer Service and Programming Technician
Futaba Service Center USA

Thanks for the reply.

I was able to special order my 4EXA configured with 75 MHZ on channel 72. I believe it was changed at the service department.

The crystal set I meant to refer to was set number LXH260** which is a dual conversion set. The recommended receiver crystal is a single conversion FUTL59**.

Will the LXH260** work for to change channels?

Do you still recommend sending transmitter to factory for just a channel change?

Mitch

I see, thanks for clarifying.

You can change the receiver crystal, but it is against FCC regulations to change the transmitter crystal unless you are an authorized service center. The transmitter must be sent in to be retuned.

Thanks, Krysta

The Futaba R127DF receiver is a DUAL CONVERSION FM receiver. You must use a dual conversion receiver crystal. The transmitter has absolutely nothing to do with single conversion or dual conversion. There is only one kind of FM transmitter crystal. There are two kinds of FM receiver crystals: single and dual conversion.

OK, thank you both for your replies. I understand now. The dual conversion set is what I need if I want to change.

Best, Mitch