It is not necessary to put the receiver in a weatherproof box.
Below the chart is a simplified diagram of how to hook the parts of the receiver together. The chart below shows an interference-free recording of the signal from NAA in Cutler, Maine, USA transmitting on 24 kHz that I made in Orlando, Florida, USA with the loop antenna 8 meters (27 feet) from the nearest 60 Hz electrical wiring. This loop antenna receiver is meant to be located outdoors so it can be placed as far as possible from electrical wiring which is the source of most if not all of the interference that plagues SES receivers. The receiver has a pass band of less than 500 Hz which compares favorably with other SES (Sudden Enhancement if Signal) receivers in use today. The low resistance of the #14 wire gives the loop a high Q, about 400 compared to about 20 for small loop antennas wound with #26 wire that are used by most SID observers. It is the LC resonant circuit for the receiver and owes its success to being a large high-Q loop with much greater aperture than small loop antennas usually used with sudden ionospheric disturbance (SID) receivers. I call this a "Loop Antenna Receiver" because the loop is the receiver. There is plenty of signal to make up for any lost on the transmission line.
There is no need to match this transmission line to the recorder driver because the signal has already been amplified 900 X. After the signal is amplified 900 times it is sent over a transmission line consisting of ordinary 4-wire telephone wire to a recorder driver. The receiver is built right on the loop antenna so there is no need for a transmission line between the antenna and the receiver. I meet the second requirement by eliminating the transmission line altogether. I meet the first requirements by building a hexagonal loop antenna that measures 1.5 meters (59 inches) across the diagonals and winding it with 24 turns of # 14 stranded copper wire. The design is based on the principle known to all amateur radio operators that the most important part of a transmitting or receiving system is a good antenna and a well matched transmission line. The loop antenna that goes with it will take another day to build from stuff you can buy at Home Depot or a similar store. You can build it in one afternoon from about $10 worth of Radio Shack parts. Here is an updated version of the simple VLF receiver first described in the April SID Supplement of the Solar Bulletin. A Simple, Easy to Build VLF Receiver to Detect Solar Flares and Gamma Ray Bursts - From the October 2002 Solar Bulletin