A LowFER Receiver Using a "Software" IF by KØLR
This article describes a "software" receiver that uses a simple, low cost hardware downconverter in conjunction with sound-card software such as DL4YHF's "Spectrum Lab" or I2PHD's "SDRadio", which act as a tunable DSP-IF system.
https://www.qsl.net/k0lr/SW-RX/sw-rx.htm

A very simple VLF Pocket receiver by DJ1WF
The following receiver concept may give an idea how to build a tiny and sufficiently performant RX without using expensive filters.
http://www.vlf.it/fritz/pocketrx.html

A VLF-LF receiver - 10kHz to 500 kHz with resistance tuning by VK5BR
The receiver design is a little different from the usual form. It has no variable capacitors or inductors except for one preset trimmer in a trap circuit. Tuning is carried out by a potentiometer, the resistance of which sets the frequency of the heterodyne oscillator.
http://www.robkalmeijer.nl/techniek/electronica/radiotechniek/hambladen/ar/1989/12/page10/index.html

An electro-mechanical RX for VLF by MØBMU
It is basically a direct conversion receiver. It has a 2 pole passive preselector with RF bandwidth of about 800Hz, which also impedance matches the antenna to the mixer. The mixer uses saturating ferrite cores, in a way not unlike the SAQ keying circuit.
http://www.wireless.org.uk/mechrx.htm

Ricevitore VLF Valvolare da IWØBZD
Nel percorso di ricerca nell’ambito delle VLF ed SLF, mirato alla ricezione estrema dei segnali di origine geologica, ho sempre adottato, nel corso degli anni, innumerevoli soluzioni sempre più innovative ed al passo con la tecnologia.
https://web.archive.org/web/20200803174942/https://www.qsl.net/iw0bzd/VLF_TUBE_RX.htm

Using a PC with soundcard as a VLF receiver by DL4YHF
This article describes how to use your PC as a receiver for narrow-band signals in the VLF radio spectrum.
https://www.qsl.net/dl4yhf/speclab/vlf_rcvr.htm

VLF/LF to 28.5 MHz Receiving Converter by DF3LP
This converter is one of my early projects and I'm not able to count all steps of reconstruction over the past 18 years. When 137 kHz became available here in Europe in 1998 I fished this old-timer out of the junk box.
https://www.qsl.net/df3lp/projects/lfconv/index.html

VLF Receiver Using Saturable Ferrite Mixer by AA1TJ
The project took less than an hour; from original conception to working receiver. I'd been playing with a saturable magnetic AM modulator on the bench, when it occurred to me that my modulator ought to work as a VLF product detector.
http://web.archive.org/web/20101124023219/http://aa1tj.com/vlfreceiverwithsaturableferritemixer.html

VLF Tube Receiver by IWØBZD
The circuit described below has been designed to match the requirements above. As main feature, it works with a single 12V source. It can be also feed with a little Ni-Cd or Pb battery, like the ones used in most anti burglar systems. Due to its low power consumption the circuit is able to work for many hours.
http://www.vlf.it/accardo/vlf_Tube_eng.html

VLF nach KW-Konverter durch DG7XO
Dieser Converter stammt von der Homepage http://www.radiosky.com ab.Ich habe dazu ein Layout für ein OM aus unserem OV gemacht, dass ich auch hier zur Verfügung stellen möchte.
http://www.dg7xo.de/selbstbau/vlf2kw.html