Hi Guys,
My 11-99 that sits by my bed has done an interesting thing last night.
It stays tuned to the same station, and I only ever turn it on & off.

Last night I turned it on and the just got static.
The radio still worked and sounded fine, but my station (4KQ - 693 kHz) was nowhere to be found.

I did find one station perhaps ABC (612 kHz) repeated some 7 or 8 times across half of the dial.
Touching the antenna screw impeded performance, where usually it causes better performance.
The sound was still great, but why this behaviour?
Even if there was a retransmission of the same thing, the dial was still all over the place.

https://www.youtube.com/watch?v=qEWWDeHD724.

It did come back good before I went to bed.
4KQ is back where it should be, and touching the antenna makes it louder.
ABC (I think it was) is no longer repeated across the dial.
Cheers, Brek.

Ghosts

I did find one station perhaps ABC (612 kHz) repeated some 7 or 8 times across half of the dial.

It's a conspiracy by the ABC to dominate the AM band.

I've never experienced anything like that, but then I live in the big smoke.

I decided to see how long it would be happy unmodified.

It was sold working and the owner is still with us, and was happy to let the radio go ;)

So it is a confusing thing to happen and go away again.

It could have a strange bug in it. I had a set, not long overhauled. Go wildly off frequency to the point I though it was a Mica cap gone feral.

Not so: It was actually a highly charged Huntsman that had committed suicide on the live end of the oscillator coil.

Works fine now its been debugged.

No need to call "Ghost Busters".. Just removed smokey RF = Really Fried

I expect it to happen again as these things usually will,
and maybe another new valve in the front end will do the trick.

So long as the sound is good I figure about half of the radio is fine.
At least 6V9, 6M5, and power supply components.

If it has old paper caps in it etc. Its likely a ticking time bomb and I would overhaul it. Have you looked inside it?

I will never power an unknown radio before checking it. I have seen & repaired some sets sold at auction as going. One of them was done so well a cap fell out.

I would not worry about the pentagrid, whose circuit is where the fault is. I would worry about what damage will be done if a wax paper or electrolytic decides to short.

I see several references on the American forum to those who power unknown radio's to see if they work & fry the transformer.

Also sounds like you need a better antenna.