I have one which works great other than the fact it will randomly break into oscillation usually when receiving a station on AM. Seems to have some trouble on FM, but not the same type.

All electrolytic caps were replaced about a year ago.

Any idea what could be the problem?

When the radio works it is excellent sounding for its size. I did do a mod to move the headphone jack to just before the volume control so it could be connected to an external amplifier for higher quality sound as the tuner section when properly working is pretty good at pulling in stations.

It sounds like you need to slightly de-tune one of the IF's. Do it when the radio is oscillating, until it just stops.

I'll take a look at that. No real big deal though as I hardly use it. Mainly got it cause I had one just like it nearly 15 years ago as a teenager.

I'll try to find some service info so I'll know what to adjust. I am not sure how new the replacement electrolytics are though as IIRC I pulled them from my stash.

Running it on batteries? If the manufacturer was keen on cutting costs, they sometimes relied on the internal resistance of the batteries being low enough to not need a large electro cap from the positive rail to the negative. However as the batteries discharge, the internal resistance increases and the isolation between stages through the low impedance supply rails is decreased - hence a bit of oscillation.

It does have a capacitor for that function. I tried with a new 9 volt and got same results.