Kenwood GP-610A Instruction Manual page 16

@ Address switch
The address of t h i s component on the GP-IB bus and the l i s t e n - o n l y mode are
set.
® GND terminal
SIGNAL: Signal grounding to which the c i r c u i t ground i s connected
FRAME : Frame grounding to which the case i s connected
Be sure to perform grounding to secure safety and to prevent malfunctions due
to external noise.
- 1 3 -