A radio navigation aid, working on ‘long wave’, which needed nothing more than the special Consol chart and a radio receiver. If the receiver had a beat frequency oscillator to make the Consol dots and dashes more distinct, so much the better, but it was essentially a simple system in which you had little more to do than to count the dots and dashes from two or more Consol transmitters. But when ships were able to use more sophisticated (and more accurate) aids, who wanted Consol? Only private owners in their little boats, so Consol was closed down.