Line Volytage frequency Interface
Hey, John, got any idea of the DC to DC converter that charged that
capacitor? What voltage did it put out? Or the time it took to charge
it? Guarantee that you won't light a flash tube with 1.5 VDC.
Move on.
Bill Hawkins
-----Original Message-----
From: J. Forster
Sent: Monday, November 28, 2011 9:43 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Line Voltage frequency Interface morphed to
batteries
Recently, I took an old disposable 35mm film camera appart. It had a
flash, powered by a 1.5 V carbon-zinc AA battery. Inadvertantly, I got
across the terminals of the flash capacitor and got a hell of a shock.
Had the current gone through the right (wrong?) place, I could well be dead.
-John
Hey, John, got any idea of the DC to DC converter that charged that
capacitor?
1 transistor, 1 transformer. The photoflash cap is 80uF 330 VDC.
What voltage did it put out?
I presume 250-300 VDC. If you really want to know I can measure it.
Or the time it took to charge it?
Maybe 2-5 seconds.
E = 1/2 C [uF] * V [KV} * V [KV]
The energy stored is 1/2* 80 * 0.25 *0.25 = 2.5 J @ 250 VDC
An external medical defibrillator is roughly 40 to 120 J.
-John
=============
Guarantee that you won't light a flash tube with 1.5 VDC.
Move on.
Bill Hawkins
-----Original Message-----
From: J. Forster
Sent: Monday, November 28, 2011 9:43 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Line Voltage frequency Interface morphed to
batteries
Recently, I took an old disposable 35mm film camera appart. It had a
flash, powered by a 1.5 V carbon-zinc AA battery. Inadvertantly, I got
across the terminals of the flash capacitor and got a hell of a shock.
Had the current gone through the right (wrong?) place, I could well be
dead.
-John
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
On Mon, Nov 28, 2011 at 7:42 PM, J. Forster jfor@quikus.com wrote:
Recently, I took an old disposable 35mm film camera appart. It had a
flash, powered by a 1.5 V carbon-zinc AA battery. Inadvertantly, I got
across the terminals of the flash capacitor and got a hell of a shock.
Had the current gone through the right (wrong?) place, I could well be dead.
Another pathological example is the implanted pacemaker. How much
voltage does it use. I bet way less then what's inside a 9V battery.
But the location and the firm contact it makes means very little
voltage is required.
One of the odd things about humans is that compared to other animals
we are very tolerant of electrocution.
Anyways the entire thread is kind of pointless the very first thing I
looked for when I wanted to measure AC line frequency was my 6V AC
wall wort power supply on the teary that the 6V secondary would match
the AC mains frequency.. I'd guess that anyone would think of a low
voltage transformer
Chris Albertson
Redondo Beach, California
I don't think touching a 9 V battery to your tongue is likely to induce
ventricular fibrillation. However, in the mid 1980's, when implantable
defibrillators were first introduced and required opening the chest to
attach 'patches' directly to the heart in order to deliver the 'shock', we
routinely induced VF by applying 9 VDC from a 9 V battery directly to the
heart. We induced VF to 'test' the system to be sure that it would be able
to resuscitate the patient if and when needed.
Now days, the device is implanted under local anesthesia with transvenous
leads very much like implanting a pacemaker. However, we still induce VF to
test the system after implantation. The devices now have elaborate
algorithms built in to be able to induce VF without the need for a 9 V
battery.
Joe
-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On
Behalf Of Malcolm
Sent: Monday, November 28, 2011 5:48 PM
To: time-nuts@febo.com
Subject: [time-nuts] Line Volytage frequency Interface
Just for the unwary I saw some statistics about causes of death a while ago.
Amongst them was the fact that, on average,
THREE PEOPLE A YEAR DIE FROM TESTING 9 VOLT BATTERIES ON THEIR TONGUES IN
THE UK.
I recently joined St John Ambulance as a volunteer and I would much rather
not have to use my CPR skills on a fellow Time Nut.
Please always think safety first.
Malcolm
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Another pathological example is the implanted pacemaker. How much
voltage does it use. I bet way less then what's inside a 9V battery.
But the location and the firm contact it makes means very little
voltage is required.
Maybe. I'd guess a 5-40 V pulse.
The 48V "battery" in POTS phone systems can kill, I believe, especially
if the person's hands are wet and salty.
One of the odd things about humans is that compared to other animals
we are very tolerant of electrocution.
The resistance of dry skin limits the current greatly.
-John
============
An external defibrillator routinely goes up to 360 joules. The original
defibrillators used a damped sinusoidal wave form generated by a capacitor
charged to a known voltage then discharged through an inductor across the
chest. The impedance across the chest is close to 50 ohms.
For a routine 200 joule shock to terminate atrial fibrillation, the peak
voltage is about 2200 V, the peak current is about 50 A and it's all over in
about 5 mSec. At 360 joules, it's close to 3000 VDC and 70 A.
Modern internal, implantable defibrillators use a 'biphasic' wave form and
typically are designed to deliver a maximum of 35 joules which equates to
about 750 VDC.
Joe
-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On
Behalf Of J. Forster
Sent: Monday, November 28, 2011 10:28 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Line Voltage frequency Interface morphed to
batteries
Hey, John, got any idea of the DC to DC converter that charged that
capacitor?
1 transistor, 1 transformer. The photoflash cap is 80uF 330 VDC.
What voltage did it put out?
I presume 250-300 VDC. If you really want to know I can measure it.
Or the time it took to charge it?
Maybe 2-5 seconds.
E = 1/2 C [uF] * V [KV} * V [KV]
The energy stored is 1/2* 80 * 0.25 *0.25 = 2.5 J @ 250 VDC
An external medical defibrillator is roughly 40 to 120 J.
-John
=============
Guarantee that you won't light a flash tube with 1.5 VDC.
Move on.
Bill Hawkins
-----Original Message-----
From: J. Forster
Sent: Monday, November 28, 2011 9:43 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Line Voltage frequency Interface morphed to
batteries
Recently, I took an old disposable 35mm film camera appart. It had a
flash, powered by a 1.5 V carbon-zinc AA battery. Inadvertantly, I got
across the terminals of the flash capacitor and got a hell of a shock.
Had the current gone through the right (wrong?) place, I could well be
dead.
-John
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
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and follow the instructions there.
Implantable pacers and defibrillators use Lithium chemistry batteries
(originally Lithium Iodide) typically around 3 VDC (BOL about 3.15 VDC, EOL
about 2.62 VDC). The typical output pulse to the heart to pace the heart is
about 2.5 VDC at about .3 mSec pulse width. However, they can be programmed
up to about 8 VDC at 1.6 mSec pulse width.
Joe
-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On
Behalf Of Chris Albertson
Sent: Monday, November 28, 2011 10:34 PM
To: jfor@quikus.com; Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Line Voltage frequency Interface morphed
tobatteries
On Mon, Nov 28, 2011 at 7:42 PM, J. Forster jfor@quikus.com wrote:
Recently, I took an old disposable 35mm film camera appart. It had a
flash, powered by a 1.5 V carbon-zinc AA battery. Inadvertantly, I got
across the terminals of the flash capacitor and got a hell of a shock.
Had the current gone through the right (wrong?) place, I could well be
dead.
Another pathological example is the implanted pacemaker. How much
voltage does it use. I bet way less then what's inside a 9V battery.
But the location and the firm contact it makes means very little
voltage is required.
One of the odd things about humans is that compared to other animals
we are very tolerant of electrocution.
Anyways the entire thread is kind of pointless the very first thing I
looked for when I wanted to measure AC line frequency was my 6V AC
wall wort power supply on the teary that the 6V secondary would match
the AC mains frequency.. I'd guess that anyone would think of a low
voltage transformer
Chris Albertson
Redondo Beach, California
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
If you look at the frequency dependence of the 'fibrillation threshold' (the
minimum energy needed to induce ventricular fibrillation), it turns out that
60 Hz is just about optimum.
Joe
-----Original Message-----
From: time-nuts-bounces@febo.com [mailto:time-nuts-bounces@febo.com] On
Behalf Of J. Forster
Sent: Monday, November 28, 2011 10:41 PM
To: Chris Albertson
Cc: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Line Voltage frequency Interface morphed to
batteries
Another pathological example is the implanted pacemaker. How much
voltage does it use. I bet way less then what's inside a 9V battery.
But the location and the firm contact it makes means very little
voltage is required.
Maybe. I'd guess a 5-40 V pulse.
The 48V "battery" in POTS phone systems can kill, I believe, especially
if the person's hands are wet and salty.
One of the odd things about humans is that compared to other animals
we are very tolerant of electrocution.
The resistance of dry skin limits the current greatly.
-John
============
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
I should have been more direct.
What does a charged flash capacitor have to do with safety concerns
for low voltage batteries touching the tongue?
You can have the last word. It's time I moved on.
Bill Hawkins
-----Original Message-----
From: J. Forster
Sent: Monday, November 28, 2011 10:28 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Line Voltage frequency Interface morphed to
batteries
Hey, John, got any idea of the DC to DC converter that charged that
capacitor?
1 transistor, 1 transformer. The photoflash cap is 80uF 330 VDC.
What voltage did it put out?
I presume 250-300 VDC. If you really want to know I can measure it.
Or the time it took to charge it?
Maybe 2-5 seconds.
E = 1/2 C [uF] * V [KV} * V [KV]
The energy stored is 1/2* 80 * 0.25 *0.25 = 2.5 J @ 250 VDC
An external medical defibrillator is roughly 40 to 120 J.
-John
=============
Guarantee that you won't light a flash tube with 1.5 VDC.
Move on.
Bill Hawkins
-----Original Message-----
From: J. Forster
Sent: Monday, November 28, 2011 9:43 PM
To: Discussion of precise time and frequency measurement
Subject: Re: [time-nuts] Line Voltage frequency Interface morphed to
batteries
Recently, I took an old disposable 35mm film camera appart. It had a
flash, powered by a 1.5 V carbon-zinc AA battery. Inadvertantly, I got
across the terminals of the flash capacitor and got a hell of a shock.
Had the current gone through the right (wrong?) place, I could well be
dead.
-John
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
I remember one tasting a battery on my tongue.
No shock, but a really nasty, bitter taste.
Not recommended.
--
Chuck Forsberg WA7KGX N2469R caf@omen.com www.omen.com
Developer of Industrial ZMODEM(Tm) for Embedded Applications
Omen Technology Inc "The High Reliability Software"
10255 NW Old Cornelius Pass Portland OR 97231 503-614-0430