Low cost earth-mode beacons?

G1KQH has found some very low cost TDA2003 ICs.  I use one of these in my VLF beacon shown in my RSGB RadCom article and on my website. Best range is just short of 6km by “utilities assisted” earth-mode.  When fitter again (currently I am not allowed to drive and I am still too clumsy when on my feet and moving because of my brain bleed last year) I intend to continue my VLF experiments. I have used these ICs at 8.97kHz, twice, and sub-multiples of that frequency.  Beyond 20kHz would be outside their spec limits, but they may still work?

G3XBM 5W VLFearth-mode CW/QRSS beacon
Evening Roger,
Used in your LF PA 10p each nuts!
Or you can buy in 10s @ 16p each inc delivery!

Banggood sounds Chinese. I have no idea if these are genuine parts or not. They are advertised as 10W car radio audio parts.

Roger Lapthorn, G3XBM, is a regular contributor to AmateurRadio.com and writes from Cambridge, England.

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