I ordered a 433 MHz RFM69HW but it came programmed to 915 MHz and will not let me change it.
The RFM69HW is marked "433 MHz" on the back, but when I read registers 07-09, is gives me 0xe4c000 which
comes out to 915 MHz. And it will not let me change registers 07 or 08. It will let me change the least
significant byte in register 09.
OK, I answered my own question. You must do three continuous writes to
registers 07,08, & 09 WITHOUT reading them in between the writes.
This allowed me to change the frequency.
Yes, stevech is absolutely correct.
These boards are optimized for labeled frequency, having specific discrete components tuned for that center frequency.
I ordered Anarduino MiniWireless wiht RFM69HW 868mHz.
I got board which is marked:
Anarduino
AW-50708
miniWireless 69.
Tell me please where on board must be marked the frequency?
On top of this board below of antenna input and left from the reset
button are marked 433 868 915.
How I can know on what frequency is tuned this module?
Thank You.