Notes:Power input is diode protected; if you reverse the polarity on the power supply, the transmitter will not work, but no damage will be done. If the LED doesn't light when the supply is connected, check your connections. (applies only to certain models)
The case of the transmitter is ground potential and connected to the negative (-) supply terminal. It's not recommended to use the Grenade with car audio sound systems, which may have an incompatible 'floating ground'.
As with any transmitter, always have an antenna connected before applying power. You can use a 50 ohm dummy load for testing, as long as it's rated at 10 watts or more. If the transmitter case gets too hot, or the audio is distorted, the antenna may be bad, or mis-tuned.
The Grenade has an automatic level control to keep the audio level from being too loud or too soft. The circuit tries to compensate for differences in input levels, but some sources might still be too loud or too soft. If using a portable, like a boombox or personal stereo, adjust it for an average listening volume through the speaker, then connect it to the transmitter.