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Why does a preamp make hum noises when I probe with a wooden chopstick around grids/wires, but a plastic pencil driver of the same length/size does not? And yet I can chopstick probe HV with impunity?
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It's weird, because it WAS working fine..... -
Was the chopstick ever used for anything? Wood is much more able to absorb things, also you are in a very humid environment?Originally posted by Enzo
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I can't rule out what g1 said about wood. Salty foods, takes on the moisture content of relative humidity, etc. Ever notice that when a guitar amp, even a vintage one is cranked up you can just get your finger tip NEAR an early grid pin and BZZZZZZZZ! Plastic doesn't absorb moisture relative to humidity or minerals from finger sweat or food. And guitar amps are typically VERY high gain. That said...
I use unused chopsticks all the time for poking. I've also used pencils and noticed that the graphite is INDEED conductive. So this seems to me like a matter of specifics. It hardly matters WHY the chopstick is conducting interference into your signal and the pencil isn't. Once the leads are arranged and the amp is in the chassis, is there a problem with stray noise being picked up? In other words, is this an amp problem? Without knowing all the specifics in minutia (like whether or not that chopstick experienced soy sauce
) it's just an exercise in speculation. If the plastic pencil works better, use the plastic pencil. In fact, take a tip and find some sort of plastic rod that doesn't even have a lead (graphite) in the middle of it. Place it in a spot on your bench and now it is THE tool that you'll use from now on.
JM2C"Take two placebos, works twice as well." Enzo
"Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas
"If you're not interested in opinions and the experience of others, why even start a thread?
You can't just expect consent." HelmholtzComment
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The chop sticks I use are at least a decade old. The "pencil" I refer to is just a descriptive, it is not a writing pencil. It is a long sturdy plastic tweaker, flat blade on one end, cone tip on the other. I would NEVER use an actual lead writing pencil, so let's get that straight. Sorry if that was not clear.
The answer "to just use what works" does not answer the question why?It's weird, because it WAS working fine.....Comment
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Insert "ionized-hair smiley thing" hereOriginally posted by Chuck H View PostIf it still won't get loud enough, it's probably broken. - Steve Conner
If the thing works, stop fixing it. - Enzo
We need more chaos in music, in art... I'm here to make it. - Justin Thomas
MANY things in human experience can be easily differentiated, yet *impossible* to express as a measurement. - Juan Fahey
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Hey! It was handy and I didn't see my chopstick close at hand, alrightOriginally posted by eschertron View Post
And I did know better than to touch any HV leads with it. I DO know that the graphite core is conductive. In fact when I fish during thunder storms (that happens in the PNW because salmon season is fall) I use fiberglass rods rather than graphite.
"Take two placebos, works twice as well." Enzo
"Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas
"If you're not interested in opinions and the experience of others, why even start a thread?
You can't just expect consent." HelmholtzComment
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I use a melamine chopstick - they're pretty common in Chinese grocers. Also a tip is to sharpen the end with a pencil sharpener for extra-fine probing ability.Comment
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That's a great idea. I have some of those but I actually use them as chopsticks. I don't want to ruin them with bench work. I actually stole them from a nice restaurantOriginally posted by Mick Bailey View Post I never thought to buy some at an Asian market. And now I don't have one around. It'll have to wait until I get to the real world (off island) sometime.
"Take two placebos, works twice as well." Enzo
"Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas
"If you're not interested in opinions and the experience of others, why even start a thread?
You can't just expect consent." HelmholtzComment
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Wood gives a more organic sound, plastic more sterile.Comment
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soldering stuff that's broken, breaking stuff that works, Yeah!Comment
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Wood can be absorbent. This COULD cause it to SWELL, and that might be GREAT. Especially helpful when amplifying pipe organs.
I think I would order some takeout and get a fresh chopstick. I had some "nice" chopsticks once. I quickly found I had to wash the damned things.
You can conduct WITH chopsticks...
And a one, and a two, and a three...Education is what you're left with after you have forgotten what you have learned.Comment
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I'm not gonna find out the hard way, I'm awfully sensitive down there.Originally posted by nosaj View Post That Persian fumble fingers guy on YouseTube may have a video out on it already. Let him zap his tweaker, at least he'll collect some good pay for it. OW OW OW OW OW - all the way to the bank!
This isn't the future I signed up for.Comment
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Plunk your magic twanger, froggy.
Education is what you're left with after you have forgotten what you have learned.Comment
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This isn't about shocking yer weenie, but it is why I don't yuse pencils to poke around in amps...
Leo, you asked for it...
https://youtu.be/5YBwDNfOaxU
Jusrin"Wow it's red! That doesn't look like the standard Marshall red. It's more like hooker lipstick/clown nose/poodle pecker red." - Chuck H. -
"Of course that means playing **LOUD** , best but useless solution to modern sissy snowflake players." - J.M. Fahey -
"All I ever managed to do with that amp was... kill small rodents within a 50 yard radius of my practice building." - Tone Meister -Comment
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As an aside, I loved his simile between pencil "lead" and "indians".
"The Europeans tried to fix it by getting rid of all the native people, but they failed." Oh yes he did
"Take two placebos, works twice as well." Enzo
"Now get off my lawn with your silicooties and boom-chucka speakers and computers masquerading as amplifiers" Justin Thomas
"If you're not interested in opinions and the experience of others, why even start a thread?
You can't just expect consent." HelmholtzComment
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