On Jun 6, 2007, at 12:08 AM, Michel Jullian wrote:
No mix-up (I knew you meant the filaments) but a misunderstanding
about what you want to measure probably.
Your use of the word "armature" in this context was confusing.
I had understood from your expression "the ability to instantly
transmit" that you were expecting a delay between emitter current
onset (= HV onset) and collector current onset, maybe due to the
flight time of whatever constitutes or initiates the filament.
By "instantly transmit" I meant the delay would not require transit
of drops carrying different potentials. There would be a large
difference in signal size between when a molecular thread is present
and when it is not. If and when the thread, or more likely threads,
are in place the signal will transmit along the threads with the
transmission characteristics of the threads.
There will be no such delay, that was my point, except of course
the subnanosecond speed of light delay for Coulomb forces to act
across a few tens of cm, even if it takes 50 milliseconds for the
"whatever" to cross the gap so that one might expect 50
milliseconds or more would elapse before current comes out the
bottom of the pan.
But that was *my* point. If threads are in place, there is a
conductor across the gap, thus the signal should travel fast across
the gap, not having to wait for insulated drops to carry the signal.
Also, I assumed the signal through an air gap should have
significantly differing and readily distinguishable characteristics,
among them a highly reduced signal size. The circuit is either
"make" or "break", thus the signal onset wold be abrupt for a circuit
designed for the transmission characteristics of the filaments.
Consider these quotes:
"I'm using an old negative ion generator as the power supply. It puts
out 10uA maximum, and maybe 10KV to 15KV."
at http://amasci.com/weird/unusual/airhard.html.
"- I connected a microamp meter in series with the plate. It
indicated zero. When I let the other HV wire create one furrow in the
mist, the meter indicated zero UA. When I brought the cable close, so
there were maybe 50 to 70 furrows being drawn along the mist, the
meter started flickering, indicating approx. 0.5uA. These ion-
streams, if that's what they are, are each delivering an electric
current in the range of 10 nanoamperes or less. Jeeze. No wonder
nobody ever notices them."
at http://amasci.com/weird/unusual/airexp.html.
Assuming a gap of about an inch for "up close" it sounds like the
resistance of the filaments is about R = V/I = (10^4 V)/(10^-8 A) =
10^12 ohm. If there were 50 of them though, as above, there would be
a .5 uA signal, which would be readily detected. Might take a pre-
amp to get it cleanly though. I don't think you would get a signal
like that though an air gap from a fine point.
Having looked at signals through a 10 m tygon tube of flowing
electrolyte, and seeing their dependence on flow rate, I would expect
some surprises regarding the signals that would be transmitted
through such filaments, assuming they exist. Anyway, moving on ...
"In pure water, sensitive equipment can detect a very slight
electrical conductivity of 0.055 µS/cm at 25°C."
See: http://en.wikipedia.org/wiki/Water#Electrical_conductivity
This gives us an estimate of the filament cross sectional area:
A = 1/((1E12 ohm/inch)*(0.055E-6 S/cm)) = 4.6E-9 m^2
and radius:
r = (A/(2 Pi))^(1/2) = 2.7E-5 m
and diameter:
d = 2*r = 5.4E-5 m = 5.4 E-3 cm
about the thickness of a human hair. So, the filament is over 10,000
water molecules wide if this is correct.
If flow is moving at the top end speed Bill estimated, about 10 MPH,
we get a flow rate per filament of:
F = (4.6E-9 m^2)*(10 MPH) = 2E-8 m^3/s = 0.02 cm^3/sec
or about 1.2 cm^3 per minute, which sounds a bit high from the
description, but maybe very roughly in the ballpark.
Regards,
Horace Heffner
On Jun 5, 2007, at 3:28 PM, Michel Jullian wrote:
If I understand correctly what you want to do it wouldn't work
Horace, the signal would be transmitted instantly regardless of the
carrier velocity. Think of the gap as a capacitor, any current
entering one armature leaves simultaneously the other armature,
independently of any "real" current between the armatures.
