LF: Antenna switching 72/136kHz

["Rik Strobbe" <rik.strobbe@fys.kuleuven.ac.be>]

In my previous mail I forgot to mention that 'parallel tuning' of the
antenna will only work with a high-impedance RX input (FET-preamp). For 50
Ohm input series tuning can be used (an additional series capacitor between
RX and loadingcoil).
This capacitor can be short-circuited to switch from 136 to 72kHz. A simple
low-voltage relais will do.
Thanks to Jim (M0BMU) to point this out.

73, Rik  ON7YD