i wanted to make an international call (to America) so i need to dial +1 etc.
i have the Sangoma S705 and there is no + on the keys, also when i hold down the 0 key (with all phones i know this will make a +) nothing happens
The + is referred to as a 'meta character` for your locales InternationalDirectDial or IDD, that will be interpreted as the locale specific digits that start an international call In North america it is dialed as ‘011’ in most other countries it is ‘00’
Your trunk provider might or might not accept and convert an initial + , you will have to check with them.
A common recommendation is to ‘normalize’ dialing so the phone, clients and address books all see the ‘conventional number’ and this is achieved for incoming calls by sending such calls to a custom context something like the [from-pstn-e164-us] NANPA specific one in /etc/asterisk/extensions. (You would construct your own [from-pstn-e164-nl] in /etc/asterisk/extensions_custom.conf to suit.)
For out going calls, then massage the number as required by your carrier but feel free to allow a more general dial pattern , i.e. accept +13235551212 as well as 0013235551212 or for NL 0031107111234 or +31107111234 or 0107111234 so soft phones would still work seamlessly.