When using a satellite phone you must realize you are communicating with a satellite hundreds of miles in orbit. The satellite signal must go up to one of the satellites and then the signal must go down to a ground station where it is then delivered to the call destination. For you to accomplish this with Globalstar or Iridium satellite phones you must be outdoors or have an external antenna outdoors with at least 80% view of the sky.
You could experience problems when using a hand held satellite phone when you are:
Indoors (without an external antenna)
Around tall buildings
Heavy Cloud Cover
Under or around trees
In a vehicle with a metal roof (without an external antenna)
Improper positioning of the antenna
Not deploying antenna
Improper dialing sequence
Not allowing phone to register (very important)
Close to other antennas and radar devices
You will have very successful usage of satellite phone when are:
Outdoors with an 80% view of the sky
You are away from tall structures and trees
Making sure the correct antenna is deployed and vertical
Making sure the antenna is properly connected (Iridium)
Allowing the phone to properly register
Avoid other antennas and radar devices commonly found on cruise ships
Wait until you receive consistent signal strength
Always follow the instructions provided
Globalstar Satellite Phones
Some additional points when using a Globalstar hand held phone would be to (wait) for it to register. This could take up to three minutes especially if you are using it outside the U.S. When it registers with the satellite constellation an inverted letter "I" will appear in the right side of the display. At that point you are free to make or receive satellite phone calls. The Globalstar has two antennas; the small antenna on the top is for the cellular portion of the phone which is not active when the unit is shipped from GlobalCom. To be able to use the Globalstar phone in satellite mode you must deploy the large antenna located at the back. This antenna should be rotated to a vertical position. When holding the phone to your ear always be aware that the antenna must be vertical or you could experience dropped calls. If you experience problems making outbound calls or receive a recording asking for a credit card number you are most likely in cellular mode which is not active when you receive the Globalstar phone. It can easily be switched to "Gstar Only" mode so it will only be in satellite mode. When traveling outside the U.S. to be able to make a outbound call you must hold the "0" key and wait till you see a "+" symbol in the display. This will allow the Globalstar phone to dial the International code for you. Then you simply dial country code, area code and the number.
When using a Globalstar hand held phone with the optional car kit which includes a external antenna or if you have purchased a fixed site unit which includes a external antenna it is very important to place the external antenna with an 80% view of the sky allowing yourself line of site to the Globalstar satellite constellation. Globalstar has 48 low earth orbiting satellites and you can be connected up to four satellites at one time but if you don't have line of site to one of the satellites you will not have service. When all else fails follow instructions.
Iridium Satellite Phones
Some additional points when using an Iridium hand held telephone would be to (wait) for the phone to register. This is not usually an issue with Iridium because you cannot dial until it registers. When the phone registers the word "Iridium" will appear on the display. Antenna connection is a very important issue when properly using an Iridium phone. There is a button on top when "accidentally" pressed will release or dis-lodge the antenna from the body. The antenna can appear to be attached but still be dis-lodged. With a poor antenna connection you will have dropped calls and most likely no service. If you are meeting all the conditions when using a satellite phone and you are using the proper dialing sequence and experience a problem, always remove the antenna and properly connect the antenna. To accomplish this you must have the antenna positioned directly down behind the phone; at that point press the button on top and then remove the antenna. While holding the button on top firmly press the antenna into the antenna connection then release the button. Dialing sequence is always important with any satellite phone. With the Iridium phone when making an outbound call always dial (00) + (country code) + (the number) + (ok) the country code for the U.S. is always "1". Proper dialing sequence is also important when making inbound calls to Iridium satellite phones. To make an inbound call to Iridium phones you have two options. The first option is dialing direct, from the U.S. dial (011) + 8816 + (the Iridium telephone number). The Iridium phone has an International number. When making an inbound call and dialing the phone direct the charges are paid by the originator of the call. The user of the Iridium phone would not be charged for this type of call. The second option is the two stage dialing service which you simply dial an Arizona number 1-480-768-2500 a recording will prompt you to enter the satellite phone number, the call is then forwarded to the satellite phone. The user of the Iridium phone would be charged for this type of inbound call.