[WaveyDipole]

I hadn't considered the possibility of UV damage. It doesn't look particularly yellow but with the fogging and under artificial light it may be hard to tell. I might have a go at t-cutting a corner to see whether it helps but I do suspect as Paul states that the damage may be well below the surface. Thank you for the explanation. Does one use ordinary auto t-cut, or is there a specific product for this?

Regarding the audio, thanks Paul. I will check the quiescent current as you suggest. The radio does generally sound pretty good and the distortion is relatively minor so although its a slight annoyance to my ear its not a major issue.

The power section seems to still have its original capacitors and from previous posts on here I gather that the smoothing can is prone to sudden failure after all these years which can take out the rectifier, so I think I will be swapping that out as a preventative measure. I haven't determined yet whether it has a selenium rectifier.

One of the faults with this unit was that the FM band was not working, however it suddenly sprung to life after the AFC switch was operated. I will clean the switches with a bit of cleaning lubricant, but since the previous owner had already done that, I am a bit puzzled. The switch is mounted separately to the chassis so it seems unlikely to be the result of mechanical pressure on the PCB.