Hi, can you put a any 40mhz crystal, into a futaba 40mhz system??? Because I heard somewhere that you have to have futaba crystals in futaba systems...

you need futaba crystals

Damn, why is that???

Every manufacturer uses different specifications on their crystals,
so it's always best to use the same brand crystals with your radio system.

Yep, with FM transmitters you can only use the crystals which are the same brand as your transmitter. AM trannies generally accept any makers crystals.

I dont know about other brands, although i had a futaba 3pj, and i picked up some generic crystals quite cheap, and never had problems with them, from memory the instruction manual said as long as they are single conversion crystals they will work.

Yes they all work I am sure. Do you really think that a manufacturer would corner the maket like that LOL.

my experience indicates that futaba and ko xtals are happy with each others systems - jr is on its own (am and fm) and i cant comment about sanwa/airtronics

I think Sanwa / Airtronics crystals would be interchangeable because Airtronics is the American label for Sanwa...

sorry, i was grouping sanwa and airtronics together, im just not sure if they will take the ko / futaba xtals