We present two multichannel systems based on a superconducting quantum inte
rference device (SQUID) for biomagnetic measurements, installed at the Univ
ersity of Chieti. Both systems have been designed for clinical and routine
use and have been developed owing to an international cooperation. The main
issues in the instrument implementation were field sensitivity and spatial
resolution, as well as flexibility and stability during operation. The fir
st system is a planar system and is devised for magnetocardiographic measur
ements. This system is composed of 74 de SQUID integrated magnetometers con
tained in a low-noise dewar: 55 sensors are measurement channels and 21 are
placed far from the subject and are used as reference channels to create s
oftware gradiometers. The second system is a helmet system and consists of
165 de SQUID integrated magnetometers to perform magnetoencephalographic re
cordings; 153 channels are distributed over a surface covering the whole sc
alp and 12 channels are used as references. The field noise of the SQUID ma
gnetometers is about 5 fT Hz(-1/2). Each system is placed in a magnetically
shielded room for eddy current shielding and magnetic shielding. The magne
tic field is recorded with sampling frequencies up to 10 kHz. The analogue-
to-digital converted data are processed on line by means of an array of dig
ital signal processors, allowing bandpass filtering, decimation and noise c
ompensation.