Lots of new hams don't understand that the S meter on their radio is only reporting the relative strength of the repeater system and NOT the signal strength of the station they are talking to unless they are in the simplex mode. When the repeater is transmitting, it may have an output greatly exceeding that of the station IT is listening to. Remember the station it hears on the input frequency of it's receiver may be on a hand held radio and only a few blocks from the "machine" or it could be a mobile radio in a vehicle out on the fringes of the repeater coverage area or a base station running a high gain antenna and 100 watts from the next county or in some cases, the next state.

To a third party, (another ham), listening to the machine on the repeater output, all of these stations would have the same S meter reading on his S meter! As long as the repeater can detect the signals and is working properly as it is setup, then all stations, (to the third ham), will "appear" to have the same signal strength on the S meter. Remember, the S meter is only reporting the relative strength of the repeater when it is transmitting and not the individual stations! So all that being said, how do you give an accurate signal report to the station you are talking to?

JUST USE PLAIN ENGLISH!

Listen to the background sounds of his AUDIO coming from your speaker in between words and sentences. Don't even look at your S meter. (Assuming the repeater has a good strong signal into your location).

If there is no noise other than room background, road, passenger or other sounds that could be picked up by his microphone, then he would be said to have a FULL QUIETING signal into the repeater.....receiver. NOT 50 OVER S9, S9, OR ANY COMBINATION on your S meter. The term "Quieting" refers to the carrier level of the transmitter being strong enough to "quiet" the background hiss on the frequency. If some background noise such as the hiss that is commonly heard in an FM receiver is heard on the transmitter signal, then it would not be considered "FULL QUIETING". 

There are times when either station using a repeater may be getting into the repeater receiver with very little signal and the repeated signal will have lots of noise on it. Although the repeater signal may be full quieting when the weak station stops transmitting, the weak station can not be considered to be full quieting into the repeater so you would give the other station a report on his signal and not the repeater. Don't get confused with this. If his audio is perfectly understandable with 100 % copy and there is NO "noise" in the background other than the above, then an accurate report for him would be, "You're full quieting and 100 % copy into the repeater. Anything less than the above is usually given in various ways using an exact as possible description of his signal. "Audio" reports are a matter of interpretation by individual ears. We as hams are in the "business" of communications , not HI FI broadcast FM! We can only sound as good as the FCC will allow our transmitters to sound! If you are having extreme difficulty copying the other station, he may also be having the same problem with you, but remember he is hearing the repeater signal, not yours direct and so are you.

Try to get him to go "simplex" if he is coming closer to you in a few minutes. See hint below. If the transmissions get so ruff that neither can copy the other, then just give your call sign and clear off the repeater for others to use while he gets closer or higher or changes his transmitting setup. Not all conversations are completed to the end under adverse conditions or operating situations....be patient.

HINT....If the station is in and out of range of the repeater you and he were using and is coming in your direction...try him on a simplex frequency! He may be loud and clear direct on simplex and only a few miles away and getting stronger all the time but he is getting farther from the repeater! Another situation that can happen during a new contact is that you and he did not exchange locations at the first of the contact. Both you and he are using a repeater 50 miles away. Then after several minutes you discover in your conversation with the other station that he is in the same town as you and only a couple of miles away! Time for simplex! Don't hog the repeater.

Simplex operation generally means station to station or direct communication on the same frequency between two stations and not using a repeater. Use the least amount of output power needed to carry on the contact. Simplex should be used when the two stations are close enough to carry on a conversation without the use of a repeater and will help in congested metro areas with a limited number of repeaters.
Simplex should always be used if possible rather than a repeater.