No dial tone troubles are fairly easy to isolate. Static troubles can be difficult to find and repair.
For both troubles the best thing to do is to get a corded telephone, and get to the NID (normally a gray box on the side of the house) and plug a known working corded telephone in here. If the trouble still exists, then you are done troubleshooting, call your local telephone company the trouble is outside, and they need to come out to make the repairs.
If the trouble goes away at this point, then you need to troubleshoot further.
I will start with no dial tone troubles, since they are the fastest and easiest to troubleshoot. After checking for dial tone, and finding it working at the NID, remove your corded phone from the test jack. Dial your number. Does it ring busy (or go straight to voice mail)? This indicates that there is a short. If there are multiple wires on the customer side of the NID remove one wire at a time, and dial into your number, or check each pair with a continuity tester. If the trouble persists, or there is no continuity on the separated wiring, go to the next set of wires until the trouble goes away, or you get continuity on one of the wires going inside. The wire that is removed has the defect on it, find the phone with no dial tone, and you found your problem, it is either the phone, the jack or the wire... first go back and reconnect this wire at the NID, then go unplug this phone, if the trouble still exists, seperate the wires at the jack, if the trouble still exists go back to the NID and connect a diffrent color wire (orange/white, yellow/black) then check, if it goes away, use this same color to reconnect the jack inside, if not you need to replace this wire, follow the instructions on my blog how to wire a telephone jack.
For static, if you read the above, you should have an idea what we are in for. but first...
do you have DSL? are your filters all in place?
is the static on a cordless phone? is the cordless a 900mhz? try changing the channel.
is the cordless a 2.4ghz? if you have wi-fi change the channel of the wi-fi ROUTER! and move the phone away from the refrigerator, and microwave. (5.8ghz and DECT phones should not have this type of interference)
Static normally only exists past the trouble, but not always. is it on every phone? try another phone at the same jack... check the jack for greenish color where the line cord plugs in, this is an indication of water damage, remove the cover to the jack and check for blackish color on the striped back copper wire, this is also an indication of water damage, if either exist, strip back the wire a little bit, and replace the jack. Also check the ends of the line cord for similar discoloration, and replace the line cord, and "coil" cord (handset cord) for corded phones...
trace the wire back to the NID checking all terminations inbetween are tight, and have no water damage.
If none of the above resolved the trouble, and the line is clear at the NID, you should replace the wiring, and jack as a staple may have punctured the wire when the wire was installed or repaired, and water may have entered somewhere in the wire, or the wire may be nearly broken. Replacing with new is going to be faster, and more effective in providing a quality connection, then searching every inch of the wire for damage, and taping the wire up.
Go to my blog how to wire a jack if you need to rewire your jack.
For both troubles the best thing to do is to get a corded telephone, and get to the NID (normally a gray box on the side of the house) and plug a known working corded telephone in here. If the trouble still exists, then you are done troubleshooting, call your local telephone company the trouble is outside, and they need to come out to make the repairs.
If the trouble goes away at this point, then you need to troubleshoot further.
I will start with no dial tone troubles, since they are the fastest and easiest to troubleshoot. After checking for dial tone, and finding it working at the NID, remove your corded phone from the test jack. Dial your number. Does it ring busy (or go straight to voice mail)? This indicates that there is a short. If there are multiple wires on the customer side of the NID remove one wire at a time, and dial into your number, or check each pair with a continuity tester. If the trouble persists, or there is no continuity on the separated wiring, go to the next set of wires until the trouble goes away, or you get continuity on one of the wires going inside. The wire that is removed has the defect on it, find the phone with no dial tone, and you found your problem, it is either the phone, the jack or the wire... first go back and reconnect this wire at the NID, then go unplug this phone, if the trouble still exists, seperate the wires at the jack, if the trouble still exists go back to the NID and connect a diffrent color wire (orange/white, yellow/black) then check, if it goes away, use this same color to reconnect the jack inside, if not you need to replace this wire, follow the instructions on my blog how to wire a telephone jack.
For static, if you read the above, you should have an idea what we are in for. but first...
do you have DSL? are your filters all in place?
is the static on a cordless phone? is the cordless a 900mhz? try changing the channel.
is the cordless a 2.4ghz? if you have wi-fi change the channel of the wi-fi ROUTER! and move the phone away from the refrigerator, and microwave. (5.8ghz and DECT phones should not have this type of interference)
Static normally only exists past the trouble, but not always. is it on every phone? try another phone at the same jack... check the jack for greenish color where the line cord plugs in, this is an indication of water damage, remove the cover to the jack and check for blackish color on the striped back copper wire, this is also an indication of water damage, if either exist, strip back the wire a little bit, and replace the jack. Also check the ends of the line cord for similar discoloration, and replace the line cord, and "coil" cord (handset cord) for corded phones...
trace the wire back to the NID checking all terminations inbetween are tight, and have no water damage.
If none of the above resolved the trouble, and the line is clear at the NID, you should replace the wiring, and jack as a staple may have punctured the wire when the wire was installed or repaired, and water may have entered somewhere in the wire, or the wire may be nearly broken. Replacing with new is going to be faster, and more effective in providing a quality connection, then searching every inch of the wire for damage, and taping the wire up.
Go to my blog how to wire a jack if you need to rewire your jack.