New wavform discovered: the sharktooth

[robin.pain@tesco.net]

:::::::::::::::::::::::::::::::
:: ::
:: ** ** ::
:: * * * * ::
:: * * * * ::
::******* ***** *****::
:: ::
:: ::
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Scientists working for the Anglian Regional Space Effort here in
Cambridge, have developed a new waveform: the sharktooth (see
oscillogram above).

Experts are already hailing this as a new scientific breakthrough,
more important than big bang theory, more revolutionary than the
microchip revolution, proving once and for all that time travel is no
longer a thing of the past.

 

[martin griffith]

On 24 Nov 2004 03:16:32 -0800, in sci.electronics.design
robin.pain@tesco.net (robin.pain@tesco.net) wrote:

:::::::::::::::::::::::::::::::
:: ::
:: ** ** ::
:: * * * * ::
:: * * * * ::
::******* ***** *****::
:: ::
:: ::
:::::::::::::::::::::::::::::::

Scientists working for the Anglian Regional Space Effort here in
Cambridge, have developed a new waveform: the sharktooth (see
oscillogram above).

Experts are already hailing this as a new scientific breakthrough,
more important than big bang theory, more revolutionary than the
microchip revolution, proving once and for all that time travel is no
longer a thing of the past.

Your search - "Anglian Regional Space Effort" - did not match any
documents. (google)




martin

Serious error.
All shortcuts have disappeared.
Screen. Mind. Both are blank.

 

[Anders F]

<robin.pain@tesco.net> wrote in message
news:bd24a397.0411240316.3070dad7@posting.google.com...

:::::::::::::::::::::::::::::::
:: ::
:: ** ** ::
:: * * * * ::
:: * * * * ::
::******* ***** *****::
:: ::
:: ::
:::::::::::::::::::::::::::::::

Scientists working for the Anglian Regional Space Effort here in
Cambridge, have developed a new waveform: the sharktooth (see
oscillogram above).

A faked oscilloscope snapshot would be more convincing ;-)

/A

Experts are already hailing this as a new scientific breakthrough,
more important than big bang theory, more revolutionary than the
microchip revolution, proving once and for all that time travel is no
longer a thing of the past.

 

[Guy Macon]

Anders F wrote:

:::::::::::::::::::::::::::::::
:: ::
:: ** ** ::
:: * * * * ::
:: * * * * ::
::******* ***** *****::
:: ::
:: ::
:::::::::::::::::::::::::::::::

A faked oscilloscope snapshot would be more convincing ;-)

(Chuckle) I once designed a system that drew vector graphics.
I hooked it up to my 465B scope and made it look like I had
a ringing square wave with a slightly negative risetime. It
looked quite convincing unless one noticed that the scope
was in X-Y mode...

 

[John Larkin]

On Wed, 24 Nov 2004 16:22:50 +0000, Guy Macon
<http://www.guymacon.com> wrote:

Anders F wrote:

:::::::::::::::::::::::::::::::
:: ::
:: ** ** ::
:: * * * * ::
:: * * * * ::
::******* ***** *****::
:: ::
:: ::
:::::::::::::::::::::::::::::::

A faked oscilloscope snapshot would be more convincing ;-)

(Chuckle) I once designed a system that drew vector graphics.
I hooked it up to my 465B scope and made it look like I had
a ringing square wave with a slightly negative risetime. It
looked quite convincing unless one noticed that the scope
was in X-Y mode...

Not to change the subject (Heaven forbid!) but you can get some cool
effects connecting the vertical input of an analog scope to a
photodetector, like a pmt, and aiming it at the screen. It can be made
to "trace" objects near the screen, like your fingers or whatever, and
it falls off the edge of objects as the sweep passes. It amused me,
anyhow, when I was about 11 years old.

John

 

[John Larkin]

On Wed, 24 Nov 2004 20:14:34 -0700, Jim Thompson
<thegreatone@example.com> wrote:

On Wed, 24 Nov 2004 19:12:17 -0800, John Larkin
jjlarkin@highlandSNIPtechTHISnologyPLEASE.com> wrote:

On Wed, 24 Nov 2004 16:22:50 +0000, Guy Macon
http://www.guymacon.com> wrote:


Anders F wrote:

:::::::::::::::::::::::::::::::
:: ::
:: ** ** ::
:: * * * * ::
:: * * * * ::
::******* ***** *****::
:: ::
:: ::
:::::::::::::::::::::::::::::::

A faked oscilloscope snapshot would be more convincing ;-)

(Chuckle) I once designed a system that drew vector graphics.
I hooked it up to my 465B scope and made it look like I had
a ringing square wave with a slightly negative risetime. It
looked quite convincing unless one noticed that the scope
was in X-Y mode...


Not to change the subject (Heaven forbid!) but you can get some cool
effects connecting the vertical input of an analog scope to a
photodetector, like a pmt, and aiming it at the screen. It can be made
to "trace" objects near the screen, like your fingers or whatever, and
it falls off the edge of objects as the sweep passes. It amused me,
anyhow, when I was about 11 years old.

John



You are easily entertained ;-)

...Jim Thompson

That's another of the many things I'm thankfull for.

John

 

[Guy Macon]

John Larkin wrote:

Guy Macon <http://www.guymacon.com> wrote:

Anders F wrote:

:::::::::::::::::::::::::::::::
:: ::
:: ** ** ::
:: * * * * ::
:: * * * * ::
::******* ***** *****::
:: ::
:: ::
:::::::::::::::::::::::::::::::

A faked oscilloscope snapshot would be more convincing ;-)

(Chuckle) I once designed a system that drew vector graphics.
I hooked it up to my 465B scope and made it look like I had
a ringing square wave with a slightly negative risetime. It
looked quite convincing unless one noticed that the scope
was in X-Y mode...

Not to change the subject (Heaven forbid!) but you can get some cool
effects connecting the vertical input of an analog scope to a
photodetector, like a pmt, and aiming it at the screen. It can be made
to "trace" objects near the screen, like your fingers or whatever, and
it falls off the edge of objects as the sweep passes. It amused me,
anyhow, when I was about 11 years old.

Cut out a chunk of cardboard, tape it on the screen, and you have
a cheap arbitrary waveform generator that even a manager can operate.

 

[Rich Grise]

On Wed, 24 Nov 2004 19:12:17 -0800, John Larkin wrote:

On Wed, 24 Nov 2004 16:22:50 +0000, Guy Macon
http://www.guymacon.com> wrote:


Anders F wrote:

:::::::::::::::::::::::::::::::
:: ::
:: ** ** ::
:: * * * * ::
:: * * * * ::
::******* ***** *****::
:: ::
:: ::
:::::::::::::::::::::::::::::::

A faked oscilloscope snapshot would be more convincing ;-)

(Chuckle) I once designed a system that drew vector graphics.
I hooked it up to my 465B scope and made it look like I had
a ringing square wave with a slightly negative risetime. It
looked quite convincing unless one noticed that the scope
was in X-Y mode...


Not to change the subject (Heaven forbid!) but you can get some cool
effects connecting the vertical input of an analog scope to a
photodetector, like a pmt, and aiming it at the screen. It can be made
to "trace" objects near the screen, like your fingers or whatever, and
it falls off the edge of objects as the sweep passes. It amused me,
anyhow, when I was about 11 years old.

If you look at TV video sync'd to the vertical, you get a side view of the
picture, and if you sync to the horizonal, you get a top view.

Cheers!
Rich

 

[Rich Grise]

On Thu, 25 Nov 2004 04:54:44 +0000, Guy Macon wrote:

John Larkin wrote:

Guy Macon <http://www.guymacon.com> wrote:

Anders F wrote:

:::::::::::::::::::::::::::::::
:: ::
:: ** ** ::
:: * * * * ::
:: * * * * ::
::******* ***** *****::
:: ::
:: ::
:::::::::::::::::::::::::::::::

A faked oscilloscope snapshot would be more convincing ;-)

(Chuckle) I once designed a system that drew vector graphics.
I hooked it up to my 465B scope and made it look like I had
a ringing square wave with a slightly negative risetime. It
looked quite convincing unless one noticed that the scope
was in X-Y mode...

Not to change the subject (Heaven forbid!) but you can get some cool
effects connecting the vertical input of an analog scope to a
photodetector, like a pmt, and aiming it at the screen. It can be made
to "trace" objects near the screen, like your fingers or whatever, and
it falls off the edge of objects as the sweep passes. It amused me,
anyhow, when I was about 11 years old.

Cut out a chunk of cardboard, tape it on the screen, and you have
a cheap arbitrary waveform generator that even a manager can operate.

And heck, who doesn't remember light pens!

Cheers!
Rich

 

[John Devereux]

John Larkin <jjlarkin@highlandSNIPtechTHISnologyPLEASE.com> writes:

Not to change the subject (Heaven forbid!) but you can get some cool
effects connecting the vertical input of an analog scope to a
photodetector, like a pmt, and aiming it at the screen. It can be made
to "trace" objects near the screen, like your fingers or whatever, and
it falls off the edge of objects as the sweep passes. It amused me,
anyhow, when I was about 11 years old.

I did that too Also made a "television" by connecting a (555)
sawtooth circuit to Y and modulating the Z input. (With the video
output from a home computer IIRC). The synchronization circuit
consisted of manually tweaking the 555 timing resistor to try to match
the video. If you got close enough it would "lock in" somehow.

--

John Devereux

 

[robin.pain@tesco.net]

John Larkin <jjlarkin@highlandSNIPtechTHISnologyPLEASE.com> wrote in message news:<46jaq0562kdeusnj3m1crb2fpe67jvs4gl@4ax.com>...

On Wed, 24 Nov 2004 16:22:50 +0000, Guy Macon
http://www.guymacon.com> wrote:


Anders F wrote:

:::::::::::::::::::::::::::::::
:: ::
:: ** ** ::
:: * * * * ::
:: * * * * ::
::******* ***** *****::
:: ::
:: ::
:::::::::::::::::::::::::::::::

A faked oscilloscope snapshot would be more convincing ;-)

(Chuckle) I once designed a system that drew vector graphics.
I hooked it up to my 465B scope and made it look like I had
a ringing square wave with a slightly negative risetime. It
looked quite convincing unless one noticed that the scope
was in X-Y mode...


Not to change the subject (Heaven forbid!) but you can get some cool
effects connecting the vertical input of an analog scope to a
photodetector, like a pmt, and aiming it at the screen. It can be made
to "trace" objects near the screen, like your fingers or whatever, and
it falls off the edge of objects as the sweep passes. It amused me,
anyhow, when I was about 11 years old.

John

You owned an oscilloscope at 11! I'm well impressed.

I owned two morse code keys that I bought from Wireless World for 7/6.
They had straps that, a local airline pilot friend-of-the-family told
me, were thigh straps. (The radio was worn on the back, apparently).

Cheers
Robin

 

[Ian]

<robin.pain@tesco.net> wrote in message
news:bd24a397.0411250037.105ded7e@posting.google.com...

I owned two morse code keys that I bought from Wireless World for 7/6.
They had straps that, a local airline pilot friend-of-the-family told
me, were thigh straps. (The radio was worn on the back, apparently).

Cheers
Robin

Reminds me of a story my father told me.

Back in the 1940's in WW2, dad worked for E.K.Cole, who made
manpack radios for the British Army. They had developed a new
version, and had the sign-off meeting with a bunch of senior guys
from the MOD and the Army.

The aerial for the set was a simple trailing wire, and this upset the
Army/MOD representatives, due to the perceived possibility of it
snagging on something in the field. This caused an impasse for a while.

It happened that there was some renovation work being done in the
building, and someone had a bright idea - they went to the builders
and got some twine (string), attached this to the end of the wire
aerial, attached a tab to it and got the squaddie who was "modelling"
the radio to tuck this in his sock.

Great! This satisfied the MOD/Army guys (never mind the real
practicality), so they signed off on the design. This was written into the
specification as "Twine, Builders". Everyone went away, happy as
Larry.

Cut to a couple of months later, production in full swing. Except....
the builders had long since gone, and they couldn't identify exactly
what twine had been used! That completely stalled shipments, as
it was in The Military Specification. The company had to trace the
builders (not that easy, it was one of those "someone knew someone"
slightly shady jobs), then find out where they had got the twine from
and buy some before they could ship the radios to the army.

Regards
Ian

 

[robin.pain@tesco.net]

"Fred Bartoli" <fred._canxxxel_this_bartoli@RemoveThatAlso_free.fr_AndThisToo> wrote in message news:<41a656c5$0$23383$626a14ce@news.free.fr>...

robin.pain@tesco.net> a écrit dans le message de
news:bd24a397.0411250037.105ded7e@posting.google.com...
John Larkin <jjlarkin@highlandSNIPtechTHISnologyPLEASE.com> wrote in
message news:<46jaq0562kdeusnj3m1crb2fpe67jvs4gl@4ax.com>...
On Wed, 24 Nov 2004 16:22:50 +0000, Guy Macon
http://www.guymacon.com> wrote:


Anders F wrote:

:::::::::::::::::::::::::::::::
:: ::
:: ** ** ::
:: * * * * ::
:: * * * * ::
::******* ***** *****::
:: ::
:: ::
:::::::::::::::::::::::::::::::

A faked oscilloscope snapshot would be more convincing ;-)

(Chuckle) I once designed a system that drew vector graphics.
I hooked it up to my 465B scope and made it look like I had
a ringing square wave with a slightly negative risetime. It
looked quite convincing unless one noticed that the scope
was in X-Y mode...


Not to change the subject (Heaven forbid!) but you can get some cool
effects connecting the vertical input of an analog scope to a
photodetector, like a pmt, and aiming it at the screen. It can be made
to "trace" objects near the screen, like your fingers or whatever, and
it falls off the edge of objects as the sweep passes. It amused me,
anyhow, when I was about 11 years old.

John

You owned an oscilloscope at 11! I'm well impressed.


Hey, why not?
I build my first own at 13. What's wrong with that?
And no, it wasn't a kit.

Heh heh, this sounds like a load of old shark's teeth to me. Now if
you said that you built a nuclear reactor in you backyard, that I
could believe -

Cheers
Robin

 

[Fred Bartoli]

<robin.pain@tesco.net> a écrit dans le message de
news:bd24a397.0411260033.75d4a0c8@posting.google.com...

"Fred Bartoli"
fred._canxxxel_this_bartoli@RemoveThatAlso_free.fr_AndThisToo> wrote in

message news:<41a656c5$0$23383> Heh heh, this sounds like a load of old
shark's teeth to me. Now if

you said that you built a nuclear reactor in you backyard, that I
could believe -

Sorry to disappoint you, but not even the slightest begining of a shark
tooth

I must admit that I cheated a bit and the time base was an adapted one from,
a Telequipment (D65 IIRC), probably because of the triggering circuit, but I
clearly remember already knowing how to obtain a linear sawtooth (no, not
shark tooth).
The CRT was a DG7-32, the only one I could buy.
All the rest, i.e. V/H amplifiers, input attenuator, blanking were home
designed.
The supply transformer was custom made for a very modest price (some nice
people took my project into sympathy).
It was even dual traces and the chassis was home made from glued aluminium
small U profiles my father used to frame large mirrors.

The same person that had the xformer wound for me then lent me a scope for
about a month so that I could debug it. I remember having had really bad
time with spurious oscillations. But with perseverence (and probably a load
of luck) it finally got to work. At least well enough for my needs of the
moment.

I used it for 3 years before buying my first commercial one (Hameg HM412).

I think I still have it in my parents' house basement. When I'll return
there, I'll try to remember to make a pic.


The main thing I gained with this experience was to not being afraid of
seemingly unreachable targets.
Serves me a lot today.

--
Thanks,
Fred.

 

[Rich Grise]

On Fri, 26 Nov 2004 08:42:28 -0800, John Larkin wrote:

On Thu, 25 Nov 2004 23:05:49 +0100, "Fred Bartoli"
fred._canxxxel_this_bartoli@RemoveThatAlso_free.fr_AndThisToo> wrote:


robin.pain@tesco.net> a écrit dans le message de
news:bd24a397.0411250037.105ded7e@posting.google.com...
John Larkin <jjlarkin@highlandSNIPtechTHISnologyPLEASE.com> wrote in
message news:<46jaq0562kdeusnj3m1crb2fpe67jvs4gl@4ax.com>...
On Wed, 24 Nov 2004 16:22:50 +0000, Guy Macon
http://www.guymacon.com> wrote:


Anders F wrote:

:::::::::::::::::::::::::::::::
:: ::
:: ** ** ::
:: * * * * ::
:: * * * * ::
::******* ***** *****::
:: ::
:: ::
:::::::::::::::::::::::::::::::

A faked oscilloscope snapshot would be more convincing ;-)

(Chuckle) I once designed a system that drew vector graphics.
I hooked it up to my 465B scope and made it look like I had
a ringing square wave with a slightly negative risetime. It
looked quite convincing unless one noticed that the scope
was in X-Y mode...


Not to change the subject (Heaven forbid!) but you can get some cool
effects connecting the vertical input of an analog scope to a
photodetector, like a pmt, and aiming it at the screen. It can be made
to "trace" objects near the screen, like your fingers or whatever, and
it falls off the edge of objects as the sweep passes. It amused me,
anyhow, when I was about 11 years old.

John

You owned an oscilloscope at 11! I'm well impressed.


Hey, why not?
I build my first own at 13. What's wrong with that?
And no, it wasn't a kit.


I admit that the scope was a Heathkit, OM-1 as I recall. I used to buy
the kits, build them, and sell them for what I paid, then buy another
one. It never ocurred to me to try to make a profit.

I slapped together a Heathkit IO-10, I believe - the one that looks like
a 465. It was about $600.00 at the time. It didn't smoke, but it didn't
work right off. So, it was time to troubleshoot, but first, have a beer.
So at the beer bar I was lamenting to my buds that the scope didn't work
yet, and I was going to have to go through it and fix it. One guy chimed
in that he had just spent $600.00 on a Scelbi-8H, one of the first home
computers. It had an 8008 and 256 bytes of RAM.

So we traded. The 'pute worked, but had to be programmed by hand through a
bank of toggle switches and a couple of pushbuttons which weren't
debounced properly.

Playing tunes was popular in those days, using loops for timing. I wasn't
satisfied with the way the ones from the books sounded, so I wrote two
overlapping/interleaved loops - one for the freq. timebase and one for the
note duration. (it seems I wrote a software emulator in Intel of the
Motorola Timer capture logic.)

Since "2001: A Space Odyssey" was extant at the time, I had it play the
tune to "Daisy, Daisy," albeit not with the words.

I was very proud.

Cheers!
Rich

 

[Fred Bartoli]

<robin.pain@tesco.net> a écrit dans le message de
news:bd24a397.0411250037.105ded7e@posting.google.com...

John Larkin <jjlarkin@highlandSNIPtechTHISnologyPLEASE.com> wrote in
message news:<46jaq0562kdeusnj3m1crb2fpe67jvs4gl@4ax.com>...
On Wed, 24 Nov 2004 16:22:50 +0000, Guy Macon
http://www.guymacon.com> wrote:


Anders F wrote:

:::::::::::::::::::::::::::::::
:: ::
:: ** ** ::
:: * * * * ::
:: * * * * ::
::******* ***** *****::
:: ::
:: ::
:::::::::::::::::::::::::::::::

A faked oscilloscope snapshot would be more convincing ;-)

(Chuckle) I once designed a system that drew vector graphics.
I hooked it up to my 465B scope and made it look like I had
a ringing square wave with a slightly negative risetime. It
looked quite convincing unless one noticed that the scope
was in X-Y mode...


Not to change the subject (Heaven forbid!) but you can get some cool
effects connecting the vertical input of an analog scope to a
photodetector, like a pmt, and aiming it at the screen. It can be made
to "trace" objects near the screen, like your fingers or whatever, and
it falls off the edge of objects as the sweep passes. It amused me,
anyhow, when I was about 11 years old.

John

You owned an oscilloscope at 11! I'm well impressed.

Hey, why not?
I build my first own at 13. What's wrong with that?
And no, it wasn't a kit.


--
Thanks,
Fred.

Note to Watson : please notice the effort I put in avoiding spaces before
the question marks