Capacitive Hats: Magic or Snake Oil?

Capacitive hats for portable whip based antennas like the MA-12 and JPC-12 are sold pretty much everywhere you can buy radio equipment now. Are they any good though? In this video I test the same antenna using WSPR with and without the capacitive hat on the same bands within a short period of time to see if the numbers can give us any results. You're welcome to join The European Ham Radio Show (TEHRS) discord at https://hamshow.eu/discord 00:00 Introduction 02:00 Unboxing and first look 04:14 Practicalities 06:40 Initial observations 07:04 More mounting details 08:08 Comparing with NanoVNA 08:59 More observations 10:59 Dutch submarine sails by (not related to test) 11:04 Summary in field 11:40 Looking at the numbers 12:22 Jupyter notebook explanation 13:32 Average SNR 14:46 Number of reports 15:11 Average distance 16:04 SNR difference for stations that heard both with and without hat 17:00 Normal distribution plot 17:28 Maps 18:36 Summary