how can i fix my big screen phillipsmagnavox projection tv?

hi, i am not sure its a wide screen tv , it a big screen phillipsmagnavox projection tv .not sure of age , but it was playing kinds off contrast seemed like , an it seemed to take a bit longer to come on an play after being off [overnite] and then the pic started to go from full screen to smaller in and out from full to about a inch all around screen back n forth '' then it would not come on at all the red power lite lites up [power lite ] .. so it is getting power , but no pic or sound at all . we cannot afford to pay a repair man to come if there's any way we can fix it ourself my husband has severe copd an cannot breathe to walk thru the house so i will be fixing it myself , an i know nothing about tv repairing so hopefully its very simple to do '' could it be the bulbs there r 3 of them an a mirrow on the back side projecting i assume , can it be a fuse or some kind of board i hear they have one ,,, where would i get the part if i knew what the problem is ? i know thi is not much info about the tv itself , i can try to move it and get the numbers from it if i need to do so let me know ,,, thanks so much, hope someone can help me ... god bless an thanks again