I was pretty sure that the 4000 CMOS range was only really good sub
1Mhz I am wrong here? please correct me
thats why I chose the 74HC series as its high speed CMOS??
On Mon, Nov 28, 2011 at 6:58 PM, ehydra ehy...@arcor.de wrote:
Maybe the HC04 oscillates but the experimenter doesn't see it. Or
On Mon, Nov 28, 2011 at 7:14 PM, Michael Malloy mech...@gmail.com wrote:
yeah it is squaring up, but not great I have already designed the
circuit boards, hmm
maybe if i replace the 74HC04 with a 74HC14 (schmitt trigger input)
which I do not have
I did make a surface mount single gate schmitt
its a shame i cannot post the picture i took is there any way to be
able to send my oscilloscope picture its 800k thats the problem
On Mon, Nov 28, 2011 at 7:29 PM, Michael Malloy mech...@gmail.com wrote:
On Mon, Nov 28, 2011 at 7:14 PM, Michael Malloy mech...@gmail.com wrote:
yeah it is
Ceramic caps can be microphonic. Just something to be on the look out.
Not so much with leaded ceramics, but more of a problem with surface mounts.
Tantalums are prone to overvoltage failure. Best to really overspec them
regarding voltage.
Note that some LDOs are not stable with really low
Kalman filtering navigation?
On Sun, Nov 27, 2011 at 4:53 AM, WB6BNQ wb6...@cox.net wrote:
Or an alcohol sensor !
BillWB6BNQ
Chris Albertson wrote:
snip
GPS is never going to be exact. Or I should say you don't know the
exact lat. long. for every place you want to go. So to
A 50K picture should fit the problem.
I successfully use 4000 series for amplifying a 5MHz PSK signal. The
HEF4x is a little faster than HCFx.
Or use a line-receiver if the oscillators is not buffered internal.
- Henry
Michael Malloy schrieb:
its a shame i cannot post the picture i took
Sorry. Read:
Or use a line-receiver if the oscillators is buffered internal.
- Henry
Michael Malloy schrieb:
its a shame i cannot post the picture i took is there any way to be
able to send my oscilloscope picture its 800k thats the problem
--
ehydra.dyndns.info
On Mon, 28 Nov 2011 19:29:41 +1100
Michael Malloy mech...@gmail.com wrote:
On Mon, Nov 28, 2011 at 7:14 PM, Michael Malloy mech...@gmail.com wrote:
yeah it is squaring up, but not great I have already designed the
circuit boards, hmm
maybe if i replace the 74HC04 with a 74HC14 (schmitt
On Mon, 28 Nov 2011 19:28:37 +1100
Michael Malloy mech...@gmail.com wrote:
I was pretty sure that the 4000 CMOS range was only really good sub
1Mhz I am wrong here? please correct me
thats why I chose the 74HC series as its high speed CMOS??
High speed is a very relative term here. It's high
On Mon, 28 Nov 2011 01:05:22 -0800
gary li...@lazygranch.com wrote:
Ceramic caps can be microphonic. Just something to be on the look out.
Not so much with leaded ceramics, but more of a problem with surface mounts.
Ceramic caps have a lot of other problems too, like capacitance
derating on
Ok to answer part of the original question.
Indeed I have see the clipped sine wave as you stated and it has no
negative component.
Numbers of vectrons and other xtal oscilators look like that. No negative
supply nor transformers so thats what you tend to get. Its normal. But as
you say feed into
Come on, folks. never hook anything directly to the power line. The
source is just too stiff. Use an opto. I used fiber optic isolation with
my big DC power supply.
Don
I used to agree, until actually tried it myself. Now this is how
I do my picPET 60 Hz data logging:
Dangerous.. A
David VanHorn wrote:
Come on, folks. never hook anything directly to the power line. The
source is just too stiff. Use an opto. I used fiber optic isolation with
my big DC power supply.
Don
I used to agree, until actually tried it myself. Now this is how
I do my picPET 60 Hz data logging:
Somewhere or another there should be a compromise that makes you happy...
you will, however, never achieve true safety as long as you are alive.
I am far more aware of this than you might suspect, but I do think that it is a
very good idea to know the risks involved.
An optoisolator is
David VanHorn wrote:
Somewhere or another there should be a compromise that makes you happy... you
will, however, never achieve true safety as long as you are alive.
I am far more aware of this than you might suspect, but I do think that it is a
very good idea to know the risks involved. An
Trust me, if you use any plug in consumer grade electronics, you already are.
Actually, we design plug-in consumer grade electronics here. No single point
of failure is allowed to present line current to the user.
___
time-nuts mailing list --
Hi Hal -
Thanks for your efforts!
I just settled down my GPS for the car on my desk (under a brick roof)
and left it over night alone. Between evening and morning I wrote 4
locations on paper and later dumped it into Google. So this is a test
case for ONE unit. It is a TomTom equipped with a
Let's not be obtuse on purpose, David.
David VanHorn wrote:
Trust me, if you use any plug in consumer grade electronics, you already are.
Actually, we design plug-in consumer grade electronics here. No single point of
failure is allowed to present line current to the user.
Let's not be obtuse on purpose, David.
No amount of dancing is going to turn this into a design that is safe by any
reasonable definition of the word.
Safe in terms of it hasn't killed anyone yet is probably true.
Safe in terms of you can trust this device not to cause a fire, no.
To quote
Do we think that failed shorted is rare?
http://www.navsea.navy.mil/nswc/crane/sd18/Public%20Documents/Resistors/ResistorsFailure.pdf
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How about a new thread with a more appropriate name to replace what
was: Clocking a PIC16F628A from a Rubidium Standard?
I don't think anyone will be interfacing anything associated with
their Rb standards directly to the AC line, except for unusual cases.
Regarding components: There are
Yes, the paper even says so.
The graph of failure rate is interesting. How useful is a graph
that shows the failure rate of a general purpose film resistor as
being from about 5E-10 to 8E-8 ?
In any case, they are saying that 5% of a (to be pessimistic) 8E-8
phenomenon results in a short
On 28/11/2011 04:00, Justin Pinnix wrote:
Sounds like a good idea for a modern handheld, but the relics we are
talking about don't have WiFi or any means of networking except for serial
and IR.
I've been wondering what to do with an old HP HX4700 for ages so it
looks like it may have a new
As part of testing the FE 5680A for aging over two weeks, all I can say
that the rate is low (2 E-12?), since temperature sensitivity masks aging.
Performing temperature tests, I get 4.3 E-12 per degree C. I plan to
temperature control the heatsink and perform additional tests and start
On Sun, Nov 27, 2011 at 8:00 PM, Justin Pinnix jus...@fuzzythinking.com wrote:
Sounds like a good idea for a modern handheld, but the relics we are
talking about don't have WiFi or any means of networking except for serial
It's 2011, almost 2012. I assumed every human over the age of 10
On Mon, 28 Nov 2011 16:16:58 -0500 (EST)
saidj...@aol.com wrote:
Use foil caps to avoid vibration-microphonics. Very expensive, but hey you
get what you pay for. Use Tantalum caps if bulk bypassing is needed, using
multiple 100uF units if necessary. The design is not right if you need more
On Mon, 28 Nov 2011 14:34:31 -0500
Chuck Harris cfhar...@erols.com wrote:
Yes, the paper even says so.
The graph of failure rate is interesting. How useful is a graph
that shows the failure rate of a general purpose film resistor as
being from about 5E-10 to 8E-8 ?
In any case, they are
I hope this is not a rehash
Has anyone tooled up and made extra output amps boards ?
If not I may see about having some blanks made.
-pete
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I hope this is not a rehash
Has anyone tooled up and made extra output amps boards ?
Not AFAIK,
If not I may see about having some blanks made.
As I remember the amps use some special coils/RF transformers. What about
getting those? I doubt HP has many, if any, in stock.
BTW, I can find no
Hi Attila,
I like 2MHz switchers because they use small components (inductors and
capacitors) and are easier to filter out at our usual frequencies of interest.
The LT3502A for example works at 2.2MHz, which gives harmonics at 8.8MHz
and 11MHz, far enough away from 10.0MHz to avoid
I found a manual PDF here
http://128.238.9.201/~kurt/manuals/manuals/HP%20Agilent/HP%205087A%20Operating.pdf
the 10 Mhz output is A12 p 8-25 and totally agree, those transformers
are unique.
desc 4-6
parts 6-9
scm's 8-25
-pete
On Mon, Nov 28, 2011 at 2:55 PM, J. Forster j...@quikus.com wrote:
You'd have to reverse engineer those. I doubt the forms cans are even
available any more.
-John
=
I found a manual PDF here
http://128.238.9.201/~kurt/manuals/manuals/HP%20Agilent/HP%205087A%20Operating.pdf
the 10 Mhz output is A12 p 8-25 and totally agree, those
I'm thinking starting from a blank PCB would be a good approach :-)
On Mon, Nov 28, 2011 at 3:19 PM, J. Forster j...@quikus.com wrote:
You'd have to reverse engineer those. I doubt the forms cans are even
available any more.
-John
=
I found a manual PDF here
Why not build a board that would physically fit, but use a modern buffer
op amp?
Pete Lancashire
I'm thinking starting from a blank PCB would be a good approach :-)
On Mon, Nov 28, 2011 at 3:19 PM, J. Forster j...@quikus.com wrote:
You'd have to reverse engineer those. I doubt the forms cans
-Original Message-
From: time-nuts-boun...@febo.com [mailto:time-nuts-
boun...@febo.com] On Behalf Of Pete Lancashire
Sent: Monday, November 28, 2011 3:25 PM
To: j...@quikus.com; Discussion of precise time and frequency
measurement
Subject: Re: [time-nuts] 5087A Output Amp PC
Threadzilla, here we come!!ote off-list.
If it gets done, and people have extra HP boards they'd like to get rid
of, please drop me a note.
-John
==
Why not build a board that would physically fit, but use a modern buffer
op amp?
Pete Lancashire
I'm thinking starting from a
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
In message 8ce7c3f5c8796a8-1410-83...@webmail-m022.sysops.aol.com, Malcolm wr
ites:
THREE PEOPLE A YEAR DIE FROM TESTING 9 VOLT BATTERIES ON THEIR
TONGUES IN THE UK.
Show me one verified coroners certificate and I'll belive you.
See also:
Ok great thank you very much I will go get some 74HC14 today if possible
and replace them, I will also upload a schematic, and a smaller picture
i tried running on a bread board with a 4000 CMOS CD40106
the output looked like a square wave through a diode to LP filter not
good, like spikes
not
I wouldnt even rely on that. a coroner in the US recently proclaimed
that the cause of death was spontaeous human combustion (again) despite
all the TV programs debunking that old wives tale.
Alan G3NYK
- Original Message -
From: Poul-Henning Kamp p...@phk.freebsd.dk
To: Discussion
Yes, that does happen (especially when dealing with medium voltage power lines).
On 11/28/2011 7:32 PM, Alan Melia wrote:
I wouldnt even rely on that. a coroner in the US recently proclaimed
that the cause of death was spontaeous human combustion (again) despite
all the TV programs
A switcher at 2.2MHz does not have single frequency spikes in its power
spectrum, but a rather wideband distribution. It is not a fixed frequency,
fixed duty cycle oscillator, but a load-dependent feedback loop that will
change duty cycle or frequency (depending on device) to maintain a target
Fun with 9 volt batteries! 8.4 x 52 =437 volts. Save those old batteries!
http://yourepeat.com/watch/?v=I2fD-hYVLxE
--
Joe Leikhim
Leikhim and Associates
Communications Consultants
Oviedo, Florida
www.Leikhim.com
jleik...@leikhim.com
407-982-0446
Note to GMail Account users. Due to an
BS!
Malcolm wrote:
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
Old hat to those of us who remember B batteries or photoflash batteries.
Try that with a couple of dozen old car batteries! Now *that* will give you a
nice arc!!
On 11/28/2011 7:44 PM, Joe Leikhim wrote:
Fun with 9 volt batteries! 8.4 x 52 =437 volts. Save those old batteries!
Maybe they choked on them?
On 11/28/2011 8:14 PM, Chuck Harris wrote:
BS!
Malcolm wrote:
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.
Chris, I think you and I are trying to accomplish different goals. I want
to be able to glance up and see (exactly) what time it is. It's just a
glorified wall clock that's always on and displaying a time. The health
information is just to validate the time.
I do have an iPad. Yes, the same
Were getting of off the original thread about Electrolytics versus other
caps a bit..
A switcher at 2.2MHz does not have single frequency spikes in its power
spectrum, but a rather wideband distribution.
Yes, that's Fourier 101 basics.
But what matters to Time nuts is if the switcher is
Every time I follow a school bus that stops at a railroad crossing and
opens its doors to stop, look, and listen - even though there is no
sign with crossed bars saying Stop, Look, and Listen and there are
many flashing red lights when a train approaches - I think of politicians
who would not put
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
Those capacitors in there can pack a wallop. I've played with various strobes
since I was very young so learned that lesson early. Short it out and see the
bang you get! (don't use your good screwdriver to do this).
Yes, I'm sure those things can be lethal.
Microwave ovens can be even
Oh, yeah, about the line interface for measurement...
I hooked up a 47k resistor from line to the 50 ohm input of my 5334B and it
just worked. I am watching the 60 Hz drift all around as I type this
(although not all that far, seems to be holding within 0.01 Hz tonight).
On 11/28/2011
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,
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
On Mon, Nov 28, 2011 at 7:42 PM, J. Forster j...@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
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
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
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
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
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-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On
Behalf Of
I'm sort of sorry I mentioned the PIC application note
While I think it's time for this thread to die I'd like to make a couple of
comments abot it tha have not been mentioned.
1/ ANY components connected directly to the mains supply should be desigined,
rated and approved for this
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