Ambulatory pH Monitoring
There are several manufacturers of compact portable recorders, which weigh between 150
and 397 g. They have similar sampling rates between 1 and 20 s, and memory sizes
between 96 and 256 kB. All are equipped with event markers and are battery-driven.
(Medtronics; Oakfield instruments; Medical Measurement Systems; Medical Instruments
Corporation; Albyn Medical; Sandhill Scientific.)