OK guys......here is the latest scoop.

Seems the Profi 403 transmitter will transmit in both AM and FM all using the same module as long as you use the Multiplex transmitter crystals.

When in AM mode, you can use ANY brand receiver. That means Hitec, Futaba, JR, Airtronics, KO, Novak, Tekin and others. The only catch is you must use the same brand of receiver crystal, meaning a Futaba receiver must have a Futaba crystal and so on. I tested this out with my Futaba gear and all is well. Neat!

When in FM mode, you cannot use Hitec or Futaba receivers or any others that are designed to be used with these brands. Apparently, according to the tech guy at Multiplex USA only receivers from JR, KO, Airtronics and Multiplex will work.

So in a nut shell, the brand new Hitec 3-channel FM receiver and the four brand new Hitec FM receiver crystals I just bought are of little use to me. I sure wish Multiplex USA had told me this before I spent all my money. I even asked and they told me I could use any brand receiver.

Anybody want to buy a receiver and some crystals?