Where To Listen
Frequencies at VLF and LF are especially vulnerable to crackly electrical noise from thermostats and motors etc. Noise from the circuitry inside TVs and monitors is also best avoided. Unsuppressed car & motorcycle engines can be a problem.
Escape to The Country!
Be about a mile (1.2Km) from domestic power lines & houses; 3 miles (3.6Km) ideally from high voltage cables. Power grids put out harmonics of the fundamental mains electricity frequency. No problems were noted on the receiver used in this project, but then, I have not used an efficient external aerial with it on VLF/LF.
When listening in countryside...stand clear of trees and vegetation. These attenuate the signals.
It is possible to get some results from this experiment in a domestic, suburban environment. Using only the Matsui MR-4099's internal ferrite rod antenna, in the English Midlands, I have picked up signals from the UK time signal station on 60KHz and some kind of data transmission around 79KHz. So the receiver definitely does work at these frequencies; more would be heard in a better location, with a better antenna coupled to the ferrite rod.