Stereo Tool

Hello, I was wondering how to fine tune a low power AM signal attached to a dummy load without causing local distortion on my test radios I use. When the modulation peaks at say 10% on the TX modulation meter, the local receivers all sound “distorted and overloaded”. I’m wondering if someone knows more about how to make a proper match between a stereo tool preset and AM signal being received right at the source and not over long distances. I’m guessing it’s my local receivers being overloaded, but I have yet to find that out. Whenever peak envelope power comes out, it’s all distorted.

I use mono audio output and I have the high pass filter set to 50 Hz. Low pass filter set to 10.000 Hz (20.000 Hz total bandwidth when monitoring the waterfall image of the signal using a SDR).

The reason for this bandwidth is simply to compare it with the source audio spectrograph peaking at the same bandwidth for fine tuning.

Test receivers are mostly if not all tube radios with an exception of the SDR that’s strictly used to monitor the RF spectrum of the signal itself.


Edit: I found the solution. The problem was with the signal itself causing overload as suspected earlier. Solution was using less gain on the receiver. Time to get back to making a nice preset dedicated to HF and regular AM.

Happy broadcasting, RTS.