This is PA0SE's shack. As you can see, Dick is a keen experimenter with many pieces of test gear.
Here is Dick taking field strength measurements with a W & G meter and an untuned single-turn loop antenna. With this system, he has made measurements at a known distance enabling him to calculate the ERP of his station.
Here is Dick's experimental 136kHz tx which has been featured in "Technical Topics". The output mosfets are on the vertical heatsinks with the driver circuitry to the left of the picture.
The schematic of PA0SEs antenna system is typical of many LF set-ups, using an HF doublet or dipole as a T aerial. Metal water or gas supply pipes make a pretty good earth!