Chosen Solution
I recently found this radio which I dont know when it was made. (date code is 5241), and the FM band does not work. AM works fine but once I turn it to FM all that happens is a low speaker hum. I tried different stereo modes and the oscillation switch but it stays the same. Is there any way to fix this?
Hi @rubix_cube , According to this webpage your radio is a boombox from the 1980’s, so most probably it will be an all transistor radio, i.e no valves, which makes it easier to get replacement parts if it turns out to be a faulty transistor. Use an Ohmmeter to check that there is continuity between the extendable antenna and where it is connected to the circuit board. Usually with these types of radios, the AM antenna is a ferrite rod type inside the case, whereas the FM antenna is an external one. Either an extendable one such as yours has (see video of your model) or a wire hanging out of the case, Also a quick check of all the capacitors in old radios is nearly mandatory as they are prone to leakage over time, although since the AM works in the radio, you may just have to check around the FM antenna coupling/ tuner/oscillator section. Have you opened the radio up at all? Sometimes with older radios the circuit diagram is to be found on the inside of the case which would be a great help
You may have to take to radio to a technician who can align the tuner. It takes a special person who knows how to do this with specialized electronic testing equipment. If it is a vintage tube radio could be a bad tube that is keeping it from bringing in stations. Make sure sure you also have an FM antenna connected to it.
At my cheap old international HPSS radio the problem was the broken cable connecting the antenna to the main printed circuit board (PCB) !!!
