David VanHorn <[email protected]> wrote: > These chips also spew harmonics if the output impedance is too far > off.
The key to a good supression of the second harmonics is to keep everything symmetric. That way, most of the 2nd harmonics that still leave the internal PA will compensate outside. It's really recommendable though to add external lowpass filters. The baluns recommended in the datasheet do already have them. But if you use a symmetric antenna, you better add two PI filters. (ETSI harmonics supression is just reachable even without them, but not much margin is left, so Tx power should be reduced a bit to gain margin. FCC harmonics supression requirements are a bit harder, and always require a lowpass filter.) -- cheers, Joerg .-.-. --... ...-- -.. . DL8DTL http://www.sax.de/~joerg/ Never trust an operating system you don't have sources for. ;-) _______________________________________________ AVR-chat mailing list [email protected] https://lists.nongnu.org/mailman/listinfo/avr-chat
