Do crt televisions make noise when they are off and plugged in

Glavinsolo

Platinum Member
Sep 2, 2004
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My fiancee swears there is a noise coming from the Television when it is turned off and plugged in. Her younger sister says she can't study with the noise. So every TV in the house is unplugged at all times. Consequently when I sit down to watch a DVD or some History channel special I have to plug the thing in and have the TV go through channel setup and what not. I don't hear this noise and I don't believe it.
 

Savij

Diamond Member
Nov 12, 2001
4,233
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71
Some do, women seem to be better at hearing it. It's annoying as hell.
 

Glavinsolo

Platinum Member
Sep 2, 2004
2,946
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Its all TVs we have 3 in the house and they claim the one at their parent's home does it as well. The TV in question is 5 years old
 

MichaelD

Lifer
Jan 16, 2001
31,528
3
76
Wow. I'm NOT crazy!

My story is a little different, but very similar.

Ever since I was a child, I could hear a very high-pitched tone coming from almost any TV (CRT) when it was turned ON. After a few seconds, the noise goes away. I have never met anyone else that agreed with me/heard the sound. :( Until now. :D

As the years passed, I read up on basic electronics, etc. It could be a choke of some kind vibrating...maybe even a capacitor charging/discharging.

Any time a CRT monitor is turned on within earshot, I hear that sound. Even from another room. With the advent of LCDs/Plasma etc, i'm hearing it less and less, which is good.

Now, as to your fiancee and her sister. There is a possiblilty that the TV could still make that sound; the capacitors hold a charge when the TV is off/unplugged. Other electronic components could similarly still be energized.

But, I have never heard the sound when the CRT is OFF; plugged in or not.
 

Demon-Xanth

Lifer
Feb 15, 2000
20,551
2
81
Depends on the TV. Sometimes a transformer in the power supply section whistles even with just the standby current.
 

lozina

Lifer
Sep 10, 2001
11,711
8
81

To remedy the situation maybe you can take them both to a few heavy metal concerts and stand right by the speakers. That oughta do it
 

tfinch2

Lifer
Feb 3, 2004
22,114
1
0
The CRT my parents used to have would turn on in the middle of the night at full volume when it wasn't plugged in.
 

PottedMeat

Lifer
Apr 17, 2002
12,363
475
126

There could be a low power switchmode power supply running at all times ( to run the microprocessor/IR receiver when you use the remote ). But aren't they usually running out of the audible range?

But I've never heard a TV running off and plugged in, but many can hear the flyback supply ( ~15KHz ? I think ) when the screen is on.
 

MichaelD

Lifer
Jan 16, 2001
31,528
3
76
Originally posted by: tfinch2
The CRT my parents used to have would turn on in the middle of the night at full volume when it wasn't plugged in.

Live in haunted houses much? :Q
 

So

Lifer
Jul 2, 2001
25,923
17
81
Originally posted by: MichaelD
Wow. I'm NOT crazy!

My story is a little different, but very similar.

Ever since I was a child, I could hear a very high-pitched tone coming from almost any TV (CRT) when it was turned ON. After a few seconds, the noise goes away. I have never met anyone else that agreed with me/heard the sound. :( Until now. :D

As the years passed, I read up on basic electronics, etc. It could be a choke of some kind vibrating...maybe even a capacitor charging/discharging.

Any time a CRT monitor is turned on within earshot, I hear that sound. Even from another room. With the advent of LCDs/Plasma etc, i'm hearing it less and less, which is good.

Now, as to your fiancee and her sister. There is a possiblilty that the TV could still make that sound; the capacitors hold a charge when the TV is off/unplugged. Other electronic components could similarly still be energized.

But, I have never heard the sound when the CRT is OFF; plugged in or not.

I believe it's the flyback transformer that you hear -- and it's well documented, lots of people hear it, I do. Although it gets harder to hear as you get older, most people over 40 can't hear such high frequencies.
 

nakedfrog

No Lifer
Apr 3, 2001
61,137
16,597
136
I wonder if they go to standby instead of turning off. My TV in the living room makes the noise when you just put it in standby, but stops if you turn it all the way off.
 

MichaelD

Lifer
Jan 16, 2001
31,528
3
76
Originally posted by: So
Originally posted by: MichaelD
Wow. I'm NOT crazy!

My story is a little different, but very similar.

Ever since I was a child, I could hear a very high-pitched tone coming from almost any TV (CRT) when it was turned ON. After a few seconds, the noise goes away. I have never met anyone else that agreed with me/heard the sound. :( Until now. :D

As the years passed, I read up on basic electronics, etc. It could be a choke of some kind vibrating...maybe even a capacitor charging/discharging.

Any time a CRT monitor is turned on within earshot, I hear that sound. Even from another room. With the advent of LCDs/Plasma etc, i'm hearing it less and less, which is good.

Now, as to your fiancee and her sister. There is a possiblilty that the TV could still make that sound; the capacitors hold a charge when the TV is off/unplugged. Other electronic components could similarly still be energized.

But, I have never heard the sound when the CRT is OFF; plugged in or not.

I believe it's the flyback transformer that you hear -- and it's well documented, lots of people hear it, I do. Although it gets harder to hear as you get older, most people over 40 can't hear such high frequencies.

Interesting read. Thanks. :)
 

dullard

Elite Member
May 21, 2001
25,765
4,290
126
Originally posted by: nakedfrog
I wonder if they go to standby instead of turning off. My TV in the living room makes the noise when you just put it in standby, but stops if you turn it all the way off.
Most CRTs that are still in existance (ie not ones made decades ago) never really turn off. They have an "instant on" feature which lets the TV turn on quickly. The "instant on" feature means the TV is on fully but the sound is muted and the screen is black. But every other part of the TV is still operating, the TV is still hot, etc.
 

Juice Box

Diamond Member
Nov 7, 2003
9,615
1
0
Originally posted by: MichaelD
Wow. I'm NOT crazy!

My story is a little different, but very similar.

Ever since I was a child, I could hear a very high-pitched tone coming from almost any TV (CRT) when it was turned ON. After a few seconds, the noise goes away. I have never met anyone else that agreed with me/heard the sound. :( Until now. :D

As the years passed, I read up on basic electronics, etc. It could be a choke of some kind vibrating...maybe even a capacitor charging/discharging.

Any time a CRT monitor is turned on within earshot, I hear that sound. Even from another room. With the advent of LCDs/Plasma etc, i'm hearing it less and less, which is good.

Now, as to your fiancee and her sister. There is a possiblilty that the TV could still make that sound; the capacitors hold a charge when the TV is off/unplugged. Other electronic components could similarly still be energized.

But, I have never heard the sound when the CRT is OFF; plugged in or not.

haha, you are not alone my friend....I could walk into a house and immediately know if someone was watching TV or not :p
 

nakedfrog

No Lifer
Apr 3, 2001
61,137
16,597
136
Originally posted by: dullard
Originally posted by: nakedfrog
I wonder if they go to standby instead of turning off. My TV in the living room makes the noise when you just put it in standby, but stops if you turn it all the way off.
Most CRTs that are still in existance (ie not ones made decades ago) never really turn off. They have an "instant on" feature which lets the TV turn on quickly. The "instant on" feature means the TV is on fully but the sound is muted and the screen is black. But every other part of the TV is still operating, the TV is still hot, etc.

Yeah. That's the standby on mine. When I turn it back on after turning it off all the way, it takes a good thirty seconds before you see/hear anything. Bought it five years ago, brand-new.