Isn't antenna maximum gain proportional to normalized area and equivalnt dielectric constant (or mu for magnetic antennas) ? Of course it is not so simple but the basic principle stays the same, no ? And active antennas always add noise and IM2,IM3 etc. Peter P. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist