Low-cost, portable ESR spectrometers with a permanent magnet of NdBFe (Neomax) containing an adjustable yoke, are developed for ESR microscopes, dosimeters and dating apparatus for field survey. The reduced price of a portable spectrometer compared to a thermoluminescence reader will increase the number of researchers in ESR dating, dosimetry and imaging as well as in education. A sample holder with anti-Helmholz field gradient coils for ESR microscopes is described.