TO ENSURE SAFETY
This Service Manual has been compiled for the purpose of facilitating repair and maintenance of the GL820
midi LOGGER by Graphtec service personnel and other persons who have undergone equivalent technical
training.
Maintenance or repair by unauthorized service personnel is to be strictly avoided. Because the GL820
contains numerous internal components with a high electric potential, such work by unauthorized service
personnel could cause human injury or serious damage to the GL820 midi LOGGER.
GL820-UM-251-9370
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