Still need some radio help

Still having some problems with the Sonomatic radio on my 1950 Buick. So far I've replaced the vibrator and the OZ4 tube, blew out the inside with canned air, checked the antenna connection (yes it's fully extended). When I turn the radio on, it comes on but all I'm getting is a stuttering noise. I've also tried adjusting the antenna trim and still nothing. Can anyone point me in the right direction?
Any help would be greatly appreciated
Scott

 

did you see about replacing the capacitors? or having someone do it for you if you're not up to the job?