Soundesign 5163 CB walkie talkie

[liammc00]

I hop this right place to post about this topic. I got this walkie talkies I while ago and now I'm trying to make them work again. The one works fine after replaceing the caps and changing the 9v battery connector but the second has bigger problem the I know how to fix. The second walkie talkie sometimes works but it most of time goes into oscillation (a loud squeal) and won't receive or transmite. The loud squeal will go away if touch the antenna. These walkie talkies work on the CB band channel 17 and schematic diagram can be found in the pictures below(schematic diagram is out of the original instruction manual).