READBACK SIGNAL COMPARISON BETWEEN DSMR AND SAL MR HEADS/

In this work, we present a comparison study of read-bask signals betwe en DSMR and SAL/MR heads. Using the reciprocity principle and the boun dary-element method, we studied read-back signals, including voltage a mplitudes, spectra and roll-off curves. Results show, if we allow the same temperature rise above ambient, the peak voltage produced by the DSMR head is about 1.4 to 2.0 times as large as that by the SAL/MR hea d, The high signal amplitude is attributed to the absence of current s hunting and more magnetic flux entering the DSMR head. Results also sh ow that both DSMR and SAL/MR heads have exactly the same characteristi c behavior in square-wave spectra within normal application regime, al though the spectrum of a DSMR head has a gap null at a very high linea r density.