Simtronics GD1 MK3 Operating Manual page 28

Enter the screen "Instrument status" and wait
for the GD1 to finish the Init procedure. In some
19
cases, it can take several minutes for "Init" to
finish.
When the GD1 is in Measuring mode check that
the noise level is OK by checking how the H
output is fluctuating. The H
20
up to ± 8 ppm*m in normal conditions.
If the noise is at an acceptable level, step 21 to
23 can be omitted.
GD1
S
2
S level can fluctuate
2
Page 28 of 76 850-816926-EN R06