I have a Lepai LP-2020A+ audio amplifier and a König FM Pocket Radio. My problem is that the pocket radio works really well on its own, with the headphone plugged in, but when I connect the radio to the amplifier through a 2xPhono to jack cable, the radio signal disappears. I suspect this is because the radio uses the cord of the headphones as an antenna, but do you guys have any suggestions on why this is not working for the amp, and how to hack the setup such that the FM radio gets a strong signal, even when connected to the amp?
closed as off topic by Olin Lathrop, Brian Carlton, W5VO♦ Aug 2 '12 at 2:04
Questions on Electrical Engineering Stack Exchange are expected to relate to electronics design within the scope defined by the community. Consider editing the question or leaving comments for improvement if you believe the question can be reworded to fit within the scope. Read more about reopening questions here.If this question can be reworded to fit the rules in the help center, please edit the question.
Well at first you should never connect earphone output to the phono input of any amp. You will overload the amps preamp stage which at least would cause you distortion or worst blow the amp. I just looked at the amp its got a mp3 input: try that. The problem you got, is that it does use the earphones has a aerial so only thing I can think of is to strip some of the plastic of to expose the shielding plus it depends on the length of the wire, all a pain. I would go out and buy another radio.