Conrad Electronic GX106 Notice D'emploi page 35

Now check the receiver properties: To do so, insert the card into a
mobile phone and check the transmission quality (normally shown on the
display) at the site where the antenna will be located.
Now insert the SIM card in the SIM support on the back of the module.
To do so, shift the cover of the SIM support slightly and fold it open.
Insert the SIM card into the cover, close it and and arrest it by sliding.
Observe the marking on the card.
The PIN code is set in the control software. When the module is turned
on while the SIM card is inserted (even if it was not configured yet), the
model tries to dial into the net with this PIN code!
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