Old Uniden PC66 lemon heads on scope?

[MKwrench]

Check this out, I've seen this before on another old am radio, but an alignment of the band pass area straightened it out.
Is anyone familiar with this, what could be causing it? It was worse, shaped like 2 halves of two different measurements put together.
This was a scrap/parts radio that I got in a pile of parts. It was in nice shape on the exterior, so I wanted to patch it up. It had a few blown traces and missing parts like the Driver and Final, the ferrite in the 54mhz trap, C70, some caps by the audio chip, and D10 was roasted and split in half. I patched everything up the best I could, used a 1957 driver and 2312 (HG part) combo. Its a beast with 7w carrier and almost 30w pep, without pinching the center (too badly), but with wierd looking lemon head peaks. lowering output does make it look better, but after seeing those higher numbers ......
Also on another note, is there a way to "speed up" the limiter on these? The usual lowering of C90 (220uf) makes the signal flutter on this one.

 

[brandon7861]

Is 30w ok for that transistor? Datasheet lists an absolute max collector dissipation of 10w, and if that class c amp is running at the worst-case of 65%, you are just exceeding that 10w limit. IDK.

What does the audio waveform look like? Is it saturating the transformer core? If the waveform looks good on the DC/audio side of the final choke, then maybe the strong audio signal is affecting the bias.

Does it do that when backed off to factory specs?

 

[MKwrench]

Is 30w ok for that transistor? Datasheet lists an absolute max collector dissipation of 10w, and if that class c amp is running at the worst-case of 65%, you are just exceeding that 10w limit. IDK.

What does the audio waveform look like? Is it saturating the transformer core? If the waveform looks good on the DC/audio side of the final choke, then maybe the strong audio signal is affecting the bias.

Does it do that when backed off to factory specs?

Thanks for the response, I should have known beter.
I played with it for a while, it cleans up under 5w deadkey with under 20pep.
But...
After adjusting it back to max again the 2312 went into a no return meltdown along with D10 until I pulled the plug. It held on as long as it could. Thats what I get for adjusting by the meter alone.
Mystery solved. I'll equate it to running a car past redline. ....OOOOF!

 

[MKwrench]

I got all exited when I saw the extra output. I'm going to play with it another day, it's a really cool little radio. We're going to see if a mosfet is better tolerated in there.