Table 1.

Frequencies of the expected harmonics and detected spectral peaks.

Expected Frequencies/MHz	Measured Frequencies/MHz
	EO Ch1 (North-South)	EO Ch2 (East-West)	D-Dot
76E-W1	76 ± 4	Not detected	Not detected
101N-S1	102.7 ± 0.6	101 ± 2	Not detected
152E-W2	149 ± 5	Not detected	148.5 ± 4.5
202N-S2	Not detected	Not detected	Not a sharp peak
228E-W3	225 ± 6	Not detected	Not a sharp peak

^E-W or ^N-S signify the mode axis, ^m=1,2,3 gives the harmonic order.