Original poster: "tesla by way of Terry Fritz <twftesla-at-qwest-dot-net>" <tesla-at-paradise-dot-net.nz> Could it be primary is tuned to a integer harmonic of secondary 1/4 wave resonance. Result multiple voltage pks on secondary ??. A tuning difference this big would have to be unexpected in a coil that has be subject to design calculation but a thought anyway. Best Ted L in NZ