Capacitor drone

I've never known capacitors themselves to make mechanical noise, if your talking about electrolytics going bad and adding hum and ripple current to a circuit, usually that happens when they dry out or leak. Many devices with large filter capacitors have big power transformers which can emit a good bit of mechanical hum noise. Maybe this is what you are hearing.
 
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I think he's talking about when a large cap charges up. Like when turning the flash on in a disposable camera. As to the why, not sure.
 
It is perfectly normal for old CRT TV sets to produce some high frequency noise. There are at least three possible fixes:
1. Replace the TV
2. Damage your hearing by exposure to loud noise.
3. Grow older

As for the TV itself, there is no repair to be made. The sound is produced by the vibration of windings in the flyback transformer, which is driven from the horizontal oscillator at a frequency of 15.734 kHz. That's a really high pitch so most people lose the ability to hear it as they approach middle age. This is a common sound that will soon disappear, like rotary dial phones and typewriters.
 
One safety warning, for anything with big capacitors, do NOT touch them, they do store lots of electricity and can be deadly, that was just in case you were thinking about poking around inside the tv to see how it worked.
Also, going even further back, when working on an old wind up gramophone, be very careful with that metal can which holds the spring, it too can be very dangerous. Sorry, I just had to throw that one in.
 
The flyback transformers in CRT's output voltages on the order of thousands of volts. Be careful with those things as well!!! You'll know it when you see it if you ever take apart something with a picture tube -- it is the component that has a single lead attaching to the side of the tube with what looks like a suction cup (but isn't). Yeah, be careful with that thing! I (thankfully) don't speak from personal experience, but I know several people who do.
 
Are you referring to the ramp up high pitch or a hissing sound? The "ramping" sound you hear is mechanical vibrations caused in the transformer as the voltage is stepped up. The transformer converts the low-voltage AC from the oscillator to changing magnetic fields, which, in turn, induce higher-voltage AC current in a second coil of wires on the transformer. The changing magnetic fields distort the transformer very slightly, and those mechanical distortions are what you are hearing. If you hear a low hiss that is usually means the cap has overheated and is leaking.
 
Wow! So much knowledge! This is why I love CB. Thanks everyone, and from you all are saying I am going with the transformer. And I guess if I want to be a lighting tech I will probably have to learn this stuff at some point?

Sent from my Galaxy S3
 
And I guess if I want to be a lighting tech I will probably have to learn this stuff at some point?

It's always good to know some electrical theory as a lighting designer/board op, but electronics is less important unless you want to get in to the repair industry (common if working at rental houses, etc). Then you will want to learn how to solder and the fundamentals of how moving lights and consoles/dimmers work. Knowing how CRT's work is kind of a "legacy" skill these days as there are fewer and fewer out in the wild.

I guess it all comes down to "define lighting tech". That said, learning the basics of electronics is never a bad idea in any field.
 
The flyback transformers in CRT's output voltages on the order of thousands of volts. Be careful with those things as well!!! You'll know it when you see it if you ever take apart something with a picture tube -- it is the component that has a single lead attaching to the side of the tube with what looks like a suction cup (but isn't). Yeah, be careful with that thing! I (thankfully) don't speak from personal experience, but I know several people who do.

27,000 volts to be exact. And those CRTs work like great capacitors, storing that voltage LONG after the set is off!
 

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