A new multi-purpose polycarbonate track detector (PCTD)/activated-carbon-fabric (ACF) radon monitor has been recently developed in our laboratory, a basic design of which was used for parametric studies. One 500 μm thick PCTD (3 cm x 3 cm) is used bare for detecting alphas from radon and progeny directly from air and another PCTD (3 cm x 3 cm) covered by an ACF layer (PCTD/ACF) to enhance the PCTD response by radon adsorption on its carbon active sites. The PCTDs were processed by 50 Hz-2 kV electrochemical etching method. The ACF/PCTD sensitivity was enhanced in respect to the PCTD/bare with an amplification factor (AF) defined as ratio of track density on PCTD under ACF to that of PCTD bare. Many ACF-related parameters studied affect the PCTD/ACF response among them thermal annealing of ACF, ACF thickness and distance of ACF layer to the PCTD are reported and discussed in this paper.