Has anyone found a service manual for this handheld? It's the newer version of the TRC-216 (40 channel, center loaded antenna, 5 pin mic jack, LCD, etc.). Nice radio, but it's developed a squeal when transmitting. I've taken it apart, removed the antenna, and hooked it up to a dummy load. Same issue, both high and low power. I can see a couple test points on the board, but the back of the board has a lot of SMT components, with nothing labeled. Thanks for any help!