We are evaluating the CC1200 and using the CC1200EMK to do some field tests. I was surprised to see there is a 10dB difference between a pair with the stick antenna and a pair with the helical antenna. I then found DN038 and now understand that the PCB helical antenna is tuned to 868MHz. I may have to change the 1pF cap and 12nH inductor as the note says. It seems TI probably has run the analysis for the best match at 915MHz. Can you help?