This ia a home built Magnetic loop antenna which was used by G3BGR, indoors on 7,10 and 14Mhz. The basic idea was in Radcom 1986
A 10 ft length of 5/16in copper tube gives a 39in diameter loop. The Gamma match is 12in of 1/8in wire spaced 1in from loop The ends of the loop are terminated with a 75pf variable capacitor and a 20pf variable to act as fine tuning.
No Antenna Matching Unit was necessary and a good match was obtained on the three bands.