Nutone 3003 repair part

I have a 3003 Master station that had been hit by lightning at least 4 times. It was repaired or replaced each time. I have so much money tied up in this unit. It still works as a doorbell but can barely hear the radio at the master staion and to turn it up you get a screeching noise. Can anyone send me the schematics and or which part to replace. I have my house up for sale and seriously need to get it repaired 1 more time as cheaply as possible. Thanks in advance

Reply