I recently purchased two Trans Portable radios. Both are in excellent cosmetic condition. One works, one doesn't. I took the covers off, but I couldn't identify the battery source. Is there a website or technical source I can tap to gain a better understanding of these radios? How do you charge them? Can the batteries be changed? Is there a source for the batteries? What does the dash radio look like? Where might I find one for sale? Any assistance you can offer would be greatly appreciated. Thanks,