John Curl's Blowtorch preamplifier part III

[Destroyer OS]

I don’t think I mentioned this before, but back to earlier about hearing frequencies... I learned recently I can hear those things meant to deter young people from loitering/skateboarding/mischief through playing higher frequencies only they can hear in the area. Be glad you cannot hear them, they grusome.

That might also explaim why I can hear strange noises from my computer that isn’t from the speakers, and no one else complains about. If I sit in the wrong place with my laptop the high pitched noises drive me crazy. I think they might have to do with WiFi, not sure.

 

[Max Headroom]

I don’t think I mentioned this before, but back to earlier about hearing frequencies... I learned recently I can hear those things meant to deter young people from loitering/skateboarding/mischief through playing higher frequencies only they can hear in the area. Be glad you cannot hear them, they grusome.

Those frequencies keep you away, what about the youngsters, the intended targets ?.

That might also explain why I can hear strange noises from my computer that isn’t from the speakers, and no one else complains about. If I sit in the wrong place with my laptop the high pitched noises drive me crazy. I think they might have to do with WiFi, not sure.

HD and fans could make HF sounds.

Are you sayin' that you are 'hearing' or sensing RF or RF modulations ?.


Dan.

 

[scott wurcer]

That might also explaim why I can hear strange noises from my computer that isn’t from the speakers, and no one else complains about.

Funny that hasn't stopped many kids from playing computer games (some almost 24/7 unfortunately).

 

[radiosmuck]

Those frequencies keep you away, what about the youngsters, the intended targets ?.



HD and fans could make HF sounds.

Are you sayin' that you are 'hearing' or sensing RF or RF modulations ?.


Dan.

I think he has Tinnitus.

 

[DF96]

I seem to recall reading of a fish and chip shop which had a problem with youths hanging around outside and making trouble. They dispersed them by playing Mozart though some external speakers. The shop was investigated for age discrimination and making a public nuisance.

 

[Zung]

Many moons ago, I worked in a classical records shop catering for the older and wealthier folks. Came closing time, we'd play "London Calling" by The Clash full blast, and that cleared the shop in record time.

 

[Tournesol]

I seem to recall reading of a fish and chip shop which had a problem with youths hanging around outside and making trouble. They dispersed them by playing Mozart though some external speakers. The shop was investigated for age discrimination and making a public nuisance.

The problem is, even if you stop playing Mozart, it will not stop the nuisance.
Because "The silence that follows Mozart is still Mozart."

 

[Max Headroom]

I seem to recall reading of a fish and chip shop which had a problem with youths hanging around outside and making trouble. They dispersed them by playing Mozart though some external speakers. The shop was investigated for age discrimination and making a public nuisance.

Trouble with gangs? Put on Manilow

By Nick Squires in Sydney
12:01AM BST 06 Jun 2006

Australians sick of the late-night music and revving engines of gangs of boy racers have unveiled a secret weapon - Barry Manilow.

Councillors in Rockdale, a suburb of Sydney, hope that the crooners' ballads will drive away the dozens of young "hoons", as boy racers are known, who are making residents' lives a misery.

Loudspeakers will belt out hits such as Mandy, I Write the Songs and Copacabana over the car park where the youths gather nightly to drink, smoke and compare souped-up cars.

Councillors believe Manilow's music is so deeply unfashionable - "daggy" in Australian slang - that teenagers will flee the area.

"Daggy music is one way to make the hoons leave because they can't stand it," Councillor Bill Saravinovski told a local newspaper.

The idea follows an experiment a few years ago in Hobart, Tasmania, where Bing Crosby music was successfully used to drive teenage loiterers out of a shopping centre.

Significant extra royalty payments for Mr Manilow, win win.


Dan.

 

[scott wurcer]

cleared the shop in record time.

So to speak, I'm an expert in clearing rooms. One hot summer day the DJ on my fave college station said OK everyone let's clear you a space on the beach.

 

[scott wurcer]

Because "The silence that follows Mozart is still Mozart."

I had a friend that was a professor of art history that told all his students to remember that Mozart was still lighting farts when he wrote most of his music.

 

[gpauk]

A good source of a sound impulse for characterising a room??

 

[chris719]

Those frequencies keep you away, what about the youngsters, the intended targets ?.



HD and fans could make HF sounds.

Are you sayin' that you are 'hearing' or sensing RF or RF modulations ?.


Dan.

It’s coil and capacitor whine from the buck converters for the CPU. When the CPU load ramps up and down it changes C states and the transients make it sing. Almost every motherboard and laptop makes noise like this.

 

[simon7000]

Does anyone here know why silicone rubber is a real no-no in nuclear submarines? And how does this affect many volume controls?

As to internal equipment environment, I am a fan of sealing the enclosure and using silica gel as both a moisture absorber and vibration damper. Also silver anti tarnish sheets are included.

Silicone rubber out gasses and causes the carbon brushes in the drive motors to fail extremely quickly.

 

[DPH]

Must be the specific formulation. Because saying silicone rubber in such a general way is the equivalent of saying "all steels are unusable outdoors uncoated" while completely ignoring the hundreds of stainless alloys.

 

[FdW]

Or steel that rust cote itself - Google Search

 

[simon7000]

Must be the specific formulation. Because saying silicone rubber in such a general way is the equivalent of saying "all steels are unusable outdoors uncoated" while completely ignoring the hundreds of stainless alloys.

Stainless also fails outdoors, it just takes longer. The Navy just bans them all, suitable other products, why risk it?

 

[simon7000]

Or steel that rust cote itself - Google Search

Which is what the US Steel Tower is made of! Now (UPMC Building!)

 

[scott wurcer]

Must be the specific formulation. Because saying silicone rubber in such a general way

The red cryo stuff is qualified for use in a fab area.

 

[Destroyer OS]

Those frequencies keep you away, what about the youngsters, the intended targets ?.


HD and fans could make HF sounds.

Are you sayin' that you are 'hearing' or sensing RF or RF modulations ?.


Dan.

If those sounds don't work on young kids they're masochists. It's not the HD or fans I hear, it could be a bad solder joint or something - it's very high pitched and reminds me of a 56k modem a little.

 

[chris719]

If those sounds don't work on young kids they're masochists. It's not the HD or fans I hear, it could be a bad solder joint or something - it's very high pitched and reminds me of a 56k modem a little.

It’s the inductors in the buck converters.