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One thing to be aware of is reflection damage. It is a phenomenon caused by impedance mismatch. If you connect a 50 ohm antenna to a transmitter and coax system designed for 75 ohms there is an impedance mismatch. Impedance mismatch on a transmission line (75 ohm coax is a good example of transmission line) has varying effects depending on how long the line is relative to the wavelength of the transmitters signal (google Smith Chart to learn more about this and it's uses). If it is at one fraction of a wavelength the transmitter will see an open circuit as the device connected to it's antenna terminals (which may or may not be good, can't remember), if it is at another fraction of a wavelength the transmitter sees a short circuit (because all the output power is reflected back into the transmitter) which means no power is transmitted and the transmitter is in danger, and at still another fraction it sees the 50 ohm antenna as a 75 ohm load (which is ideal).
In the early days of SS transmitters the short condition (all power reflected back) would usually destroy the output transistors....More recently reflection traps were devised to protect the outputs, but they are not infallible, and if damaged can block/attenuate forward signal flow, or allow enough reflected power to reach the outputs to cause damage. Your units traps or outputs could be damaged.
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