Found this thread from a search and thought I'd reply, since I have one.
A manual isn't really necessary if the converter works.
The AM output is set at the factory to about 1400kHz.
There's a screwdriver adjustment on the bottom of the unit that lets you change the output frequency if there is a local station broadcasting at 1400. If that's the case, tune in a strong FM station. You should be able to hear it along with the local AM station. Turn off the converter and tune the AM radio slightly until you can't hear the station, then turn the converter back on and adjust the output until the FM station comes in clear.
If it's mounted under the dash using the bracket, the adjuster may be easy to get to from below. Otherwise you may have to remove the converter. It should still work because the unit will still have a ground through the antenna connectors.
Other than that, there's not much to it. They work pretty good.
