Problem with AA5, very loud oscillating sound

[joostmee]

Why is the output of the 12AT6 going to the grid of the 12BE6? I'm sure it's simple, but i'm new to this....

[joostmee]

Why is the output of the 12AT6 going to the grid of the 12BE6, i'm sure it's simple, but i'm a nube.

[AllAmericanFiveRadio]

Thanks joostmee

It is known as a cascade amplifier and they are very common, their everywhere. The 12BE6 amplifies the output of the 12AT6 even more. So each stage of a cascade amplifier amplifies the output signal from the previous stage, increasing the amplification as the signal progresses through the amplifier. Hope this helps.

[joostmee]

@AllAmericanFiveRadio Oh ok I get it, for some reason i was thinking left to right on the tubes, now i see where the 12BE6 hops over to the 5OB5...

[Druidemporor]

what keeps the audio current from traveling through the cap. also? i dont understand how that componant takes in the RF current and not the Audio currrent, also i find it intresting that it doesn't go: the RF current stays in the curcuit and the audio is grounded ... hmmmm ... if that makes sense... but now that i look i think some1 asked something similar to my question

73, Ben

[AllAmericanFiveRadio]

Hey Ben,

How radio components work and there frequency characteristics is an interesting study. I have put up three video responses to this video that should help. Rick.

[akouo01]

C5 took care of that problem, and it's amazing really to see the effect of it's absence. Every little component counts. I'm Glad that all those schematics are available, I have been trying to find a schematic for a Simpson 215 from 1938, and I just am having no luck, but anyway, loved the video Rick! It was awesome! Thanks -Robert

[AllAmericanFiveRadio]

Yep, they don't put in any extra parts for fun. Hope you find the schematics, keep looking they will show up sometime. Thanks.

[HD7100]

Thanks for posting this. It is interesting to see the importance that a tiny capacitor plays in making a radio work correctly.

[AllAmericanFiveRadio]

No unnecessary parts here.

[FelixTheHouseFreak]

But why does the RF drain away through the capacitor? What makes it so attracted to go through the capacitor and not just follow the audio signal anyway? And how come the audio signal doesnt follow the RF when its draining away also?

Theres so many little things i still dont understand. ):

[AllAmericanFiveRadio]

It has to do with frequency response and resonance. There is a large difference in frequency between audio and RF. And all electronic energy will take the easiest path. RF energy sees C5 as a very easy path to ground and the audio energy does not.

[Maxxarcade]

That's interesting, I wonder why they chose to put the volume control there, instead of in the grid of the audio output tube?

[AllAmericanFiveRadio]

Your sure could put it in the output. I think it is easier to control the volume when it is not as strong.

[IceStorm5555]

Nice video as usual.

Best Regards,

IceStorm

[AllAmericanFiveRadio]

Thanks.

[jenko701]

Home run, good video .That pesky rf ,You cant live with it ,you cant live with out it.

[AllAmericanFiveRadio]

Thanks. Rf in the wrong place can cause some interesting distortion problems.