Radio issue 95 Riviera

Recently purchased a 95 Riviera..has the concer ii.. the car had been sitting for awhile..when i first checked it out the antenna worked.. never did check radio though.. the antenna now does not come up. When i power on the radio a prexisting radio station shows up briefly with the volume showing 4 dashes.. then it goes to blank dashes.. Clock i assume.. i can put a cassette or cd in and eject.. but none of the volume controls work ..steering or deck mounted.. no sound of course.. and the other buttons do nothing...etc.. any ideas?

Should the sound system still function if the power antenna does not operate..cd ..cassette..still play..etc?

Yes, regardless of the antenna function, the radio should function. Sounds like the radio is defective.