Home |
Search |
Today's Posts |
#41
Posted to rec.audio.tubes
|
|||
|
|||
At power on tube filaments light up more than normal for a sec
"flipper" wrote in message ... On Tue, 09 Dec 2008 09:14:29 GMT, Patrick Turner wrote: flipper wrote: On Tue, 09 Dec 2008 07:19:16 GMT, Patrick Turner wrote: Phil Allison wrote: "Arny Krueger" Electricity flows at the speed of light, ** ROTFL !! But heat travels down a wire at the speed of a sick snail. and the whole tube is in a vacuum. ** Yeah - vacuums are real *******s, they really suck. The thermal intertia of the components the filament contacts would be a possible variable. ** Hey - no fooling. Amazing how everyone has already thought of that !!!! Most tubes that have separate and symmetrical sides are are duals, and they seem to light up about the same. ** My god - that is an inspired insight ...... There might be far less flash at the tops of tubes because the filament wires are just barely poking out, while the ones at the bottom run all the way down to the pins. ** IME - there are those that are " top flashers " and there are those that are " bottom flashers ". And I am speaking of tubes, not people. ...... Phil Phil, looks like I was right. Not quite. I posted the same quote and while it's probably sufficient to allay the concerns of a home user it's not technically correct. For example, the description that "So in effect one side of the tube always warms up 1st" makes no sense. It also seems he got a bit confused with the heater wiring. Remember, a 12AX7 has a center tapped heater and it appears to me that he confused the two going to pins 4 and 5 as 'one side' with the one going to pin 9 as the 'other side'. At any rate, I did look at mine and it's simply that the insulation doesn't extend all the way to the pin weld so a portion of the bare filament is exposed. His explanation for the flash is also incomplete. It isn't just the "very little resistance." It's the lower thermal mass of the uninsulated segment that warms faster than the rest so it's resistance increases faster and causes more voltage drop across it, increasing the power dissipated in that segment, till the remainder of the heater warms to operating temperature. I seriously doubt that 50-75 mils out of the entire heater length has a significant effect on the overall surge and the instantaneous initial peak would still be the same since the 'whole thing' starts off cold. The surge lasts a much shorter time if part of the heater or an additional link installed is allowed to glow like a lamp filament at turn on. Actually, if it had any effect, which is doubtful because of the minuscule section affected, the surge would last longer because it would 'limit' (sic) the power input, so the rest would take longer to heat. Just what the makers did to get the flash is not clear until someone provides evidence of exactly how it was done. I suggest someone smash open an old flasher and see what's inside. I'm too busy with orders for new amplifiers. I already told you I *looked* and it's nothing more than the last few mills of the heater wire having no insulation. Which illustrates the danger of allowing a hypothesis to inform an observation, rather than vice-versa. If Patrick's initial answer were correct, and if there is a seperate link of special wire in series with the heater, then it could look just like you have seen. What you can not see by your inspection is your "nothing more than". How do you know that the rest of the heater wire is the same as what you see? How do you know that you are not looking at the "special link"? I am quite happy to accept that some flashers depend on an exposed length of heater wire which is otherwise identical to and continuous with the rest. But not on the basis of your woefully inadequate observations. And to establish that they are *all* like that would take more than observation, practically. You would need intelligence. Ian |
#42
Posted to rec.audio.tubes
|
|||
|
|||
At power on tube filaments light up more than normal for a sec
Ian Iveson wrote:
Ian Bell wrote Actually, in a conductor electricity does not 'flow at the speed of light' the net flow of electrons in a conductor is barely a few meters per second. Two different things, depending on what you think electricity is. Flow of electricity happens much faster than your surely quaint "net flow of electrons". Of course, hence the ,pedant/pedant tokens. Sorry. Sometimes I fall prey to the temptation to be clever. Actually I know sod all about electricity. I lost the plot after the Bohr atom. These days I think of standing waves, but not very clearly. Being a materialist, I have some issues with explanations that place probability in the real world. Me too. And I believe there are possible new theories that don't require it I am pleased to say. The question "What is electricity?" is problematic, to say the least. Agreed!! It's really a question for the theorists and physicists. As an engineer I an just thankful that electricity 'is' and I have empirical rules for working with it ;-) Cheers Ian cheers, Ian |
#43
Posted to rec.audio.tubes
|
|||
|
|||
At power on tube filaments light up more than normal for a sec
Ian Bell wrote:
Ian Iveson wrote: Ian Bell wrote Actually, in a conductor electricity does not 'flow at the speed of light' the net flow of electrons in a conductor is barely a few meters per second. Two different things, depending on what you think electricity is. Flow of electricity happens much faster than your surely quaint "net flow of electrons". Of course, hence the ,pedant/pedant tokens. Sorry. Sometimes I fall prey to the temptation to be clever. Actually I know sod all about electricity. I lost the plot after the Bohr atom. These days I think of standing waves, but not very clearly. Being a materialist, I have some issues with explanations that place probability in the real world. Me too. And I believe there are possible new theories that don't require it I am pleased to say. Problem is the real world doesn't mind if you have issues, it still keeps working the way it does. Have you any links to those new theories it would be stunning if they replace the last 100 years of physics, especially QED. -- Nick |
#44
Posted to rec.audio.tubes
|
|||
|
|||
At power on tube filaments light up more than normal for a sec
Nick Gorham wrote:
Ian Bell wrote: Ian Iveson wrote: Ian Bell wrote Actually, in a conductor electricity does not 'flow at the speed of light' the net flow of electrons in a conductor is barely a few meters per second. Two different things, depending on what you think electricity is. Flow of electricity happens much faster than your surely quaint "net flow of electrons". Of course, hence the ,pedant/pedant tokens. Sorry. Sometimes I fall prey to the temptation to be clever. Actually I know sod all about electricity. I lost the plot after the Bohr atom. These days I think of standing waves, but not very clearly. Being a materialist, I have some issues with explanations that place probability in the real world. Me too. And I believe there are possible new theories that don't require it I am pleased to say. Problem is the real world doesn't mind if you have issues, it still keeps working the way it does. Have you any links to those new theories it would be stunning if they replace the last 100 years of physics, especially QED. No direct link but if memory serves I read it in New Scientist about a month ago (just in passing in the supermarket whilst the missus was looking at clothes or something - you know how it is). Cheers Ian |
#45
Posted to rec.audio.tubes
|
|||
|
|||
At power on tube filaments light up more than normal for a sec
Nick Gorham wrote:
Actually, in a conductor electricity does not 'flow at the speed of light' the net flow of electrons in a conductor is barely a few meters per second. Two different things, depending on what you think electricity is. Flow of electricity happens much faster than your surely quaint "net flow of electrons". Of course, hence the ,pedant/pedant tokens. Sorry. Sometimes I fall prey to the temptation to be clever. Actually I know sod all about electricity. I lost the plot after the Bohr atom. These days I think of standing waves, but not very clearly. Being a materialist, I have some issues with explanations that place probability in the real world. Me too. And I believe there are possible new theories that don't require it I am pleased to say. Problem is What problem? the real world doesn't mind if you have issues, Yes it does. I am part of the real world. My issues *are* real. Yes it does. Our effect on the real world has been profound, and continues to be so. Wake up. At least you realise that the real world has a mind, so I'll give you some credit there. it still keeps working the way it does. In what way is it possible for anything *not* to work the way it does? What point are you making? Have you any links to those new theories If you depend for your science on links provided in news groups, there is a good chance you will fail to progress beyond your idealistic position of naive materialism. The world cares about you; you owe it some sympathy. Make an effort. it would be stunning if they replace the last 100 years of physics, especially QED. Science makes progress all the time, in fits and starts. If you allow yourself to be stunned by this, you'll be continually short-handed in the consciousness department. Even if Ian and I do nothing more for science than whinge and drag our feet, we contribute much more than those who blindly acquiesce. We are part of the real world. We care. Have some respect. Ian |
#46
Posted to rec.audio.tubes
|
|||
|
|||
At power on tube filaments light up more than normal for a sec
Ian Iveson wrote:
Nick Gorham wrote: Actually, in a conductor electricity does not 'flow at the speed of light' the net flow of electrons in a conductor is barely a few meters per second. Two different things, depending on what you think electricity is. Flow of electricity happens much faster than your surely quaint "net flow of electrons". Of course, hence the ,pedant/pedant tokens. Sorry. Sometimes I fall prey to the temptation to be clever. Actually I know sod all about electricity. I lost the plot after the Bohr atom. These days I think of standing waves, but not very clearly. Being a materialist, I have some issues with explanations that place probability in the real world. Me too. And I believe there are possible new theories that don't require it I am pleased to say. Problem is What problem? The problem that QM produces results that are not in line with common sense. the real world doesn't mind if you have issues, Yes it does. I am part of the real world. My issues *are* real. No they are not, they are entirly subjective. Yes it does. Our effect on the real world has been profound, and continues to be so. Wake up. At least you realise that the real world has a mind, so I'll give you some credit there. it still keeps working the way it does. In what way is it possible for anything *not* to work the way it does? What point are you making? The point that because our current theories don't make sense to most peoples ape brains in not a reason for them to not provide a good model of how the world operates. Have you any links to those new theories If you depend for your science on links provided in news groups, there is a good chance you will fail to progress beyond your idealistic position of naive materialism. The world cares about you; you owe it some sympathy. Make an effort. As opposed to "a copy of new scientist that was browsed while out shopping", doesn't seem any better way of gathering information. it would be stunning if they replace the last 100 years of physics, especially QED. Science makes progress all the time, in fits and starts. If you allow yourself to be stunned by this, you'll be continually short-handed in the consciousness department. Maybe so, your point being? Even if Ian and I do nothing more for science than whinge and drag our feet, we contribute much more than those who blindly acquiesce. We are part of the real world. We care. Have some respect. Ian Bad day at the office was it? -- Nick |
#47
Posted to rec.audio.tubes
|
|||
|
|||
At power on tube filaments light up more than normal for a sec
This doesn't answer any questions, but Mullard made filiments like so.
http://www.r-type.org/static/add045.htm http://www.r-type.org/static/add044.htm |
#48
Posted to rec.audio.tubes
|
|||
|
|||
At power on tube filaments light up more than normal for a sec
RS McCown wrote: This doesn't answer any questions, but Mullard made filiments like so. http://www.r-type.org/static/add045.htm http://www.r-type.org/static/add044.htm Tungsten wire making goes on today in a big way because of the many different applications of the use of tungsten. Its a tough metal with a melting point over 3,400 degrees centigrade making it ideal for a tube cathode or a tube cathode heating element where if it runs at about 900C it is under little stress and very unlikely to easily fail, especially in a vacuum of a tube. So no need to feel anxious about the tube cathodes stressing out. They are very reliable. Unless some idiot connects too much voltage and current. http://www.tungsten.com/mtstung.html Also of interest about tungsten, http://www.tungsten.com/tunghist.html Its easy to take this stuff for granted but without tungsten we might not be able to have tubes. Patrick Turner. |
#49
Posted to rec.audio.tubes
|
|||
|
|||
At power on tube filaments light up more than normal for a sec
Jan wrote:
Flashing heaters, another reason to go solid state. Jan That's no reason at all since it's perfectly normal for some brands of tubes to glow bright for an instant during power up. A lot of the Serbian made Ei tubes such as ECC83 & 12DW7 behave this way & they sound great. Many of the Mullard NOS tubes do the same thing. Perfectly normal. |
Reply |
|
Thread Tools | |
Display Modes | |
|
|