Mitsubishi MELSEC-A Series Reference Manual page 115

5. SPECIFICATIONS
POINT
(1) Use caution as follows when soldering the contact to the internal conductor.
(a) Solder must not be pumped up at soldering part.
(b) The tail end of the contact and the cut end of the insulator must contact
close to each other. Also, the contact must not cut in the insulator.
(c) Apply solder quickly so that the insulator may not deform.
(2) Before connecting or disconnecting the coaxial cable connector, be sure to
touch a grounded metal object to discharge the static electricity from the
human body.
Failure to do so may harm the module.
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