AM Signal Booster?

I am a talk radio nut also. I really got tired of the noisy signals, etc. The solution: Smartphone with Iheartradio and Tunein radio app, bluetoothed to the radio in the vehicle. Clear Channel owns Iheartradio and you can get all of the stations from across the nation, crystal clear. If your new radios don't have bluetooth then look for a USB connector. The streaming stations do not use up that much data and you will be very pleased with the choice of stations. I think transmitted radio signals will be a thing of the past in the near future as more people start streaming. Iheartradio is betting on it.... I know this didn't answer your question about boosting the quality of signal to your current radios, but this solution will make you very, very happy. Give it a try with your wife's smartphone.