Re: Risetime calculator (in tekwiki)

amirb

yeah, I think that explains it , thanks!

but the scaling on those 4 pots look identical and all segments seem to be evenly spaced (linearly scaled?)

so have they designed a specially tapered potentiometers?
I don't think logarithmic pots could approximate that mathematical expression. Perhaps a "square law" taper can do that
if you square both sides of the expression, it becomes a simple addition of squares...

still the idea of a bridge that could work based on balancing the power would have been nice though ... .

On Fri, Jan 17, 2020 at 11:14 PM, Harvey White wrote:

Perhaps I can help a bit.

Look at some of the sliderule scales if you can.  If you wanted to do
addition, the scales would be linear.  If you wanted to do
multiplication, they would not be.  You move the slides and 2*2 aligns
with 4.  4*4 aligns with 16.  If you had pots, then while the pots can
be linear, and you may or may not compute each step as if it were linear
(and you probably wouldn't), when you balance the bridge, you want the
final pot to read a value that's the result of the equation.

in other words, if you have 1 and 1, the result scale needs to balance
at 1.  If you have 2 and 2, the result scale needs to balance at 1.414 *
2, or 2.828.  Mark that value as 2.828.  You have to balance the two
legs to an equal voltage.  Even if the pots are linear, you mark them
with the appropriate scale values to solve the equation.

Harvey

On 1/17/2020 10:48 PM, amirb wrote:
Roy
sorry my mistake, I only meant why/how this thing can calculate square root
of sum of squares (should not have used rms for that perhaps)
obviously there are no sinusoidal voltages or anything like that in this
device.

and so far nobody here knows exactly how this device works. Yes it is based
on a bridge that when balanced you can read the answer on the
4th pot, That operation was pretty obvious by looking at the front panel. It
appears to only have bunch of resistors (5 pots for calibration and 4 on the
front panel plus
bunch of fixed resistors) and yet it does a nonlinear calculation or at
least approximates a nonlinear expression that involves square root, but how?
nobody has explained that really.

It seems that it must be balancing the power in one resistor (4th pot) with
the sum of powers in three other resistors!
but I have not seen a bridge that can do this...

I tried to draw the schematics by looking at that picture but I got lost in
the middle of it...

On Fri, Jan 17, 2020 at 08:50 PM, Roy Thistle wrote:

On Fri, Jan 17, 2020 at 07:57 AM, amirb wrote:

why it will produce RMS
Hi amirb, et. al.:
If by RMS you mean "root mean square" … and if there are three cascaded
systems with, for example, 90 degree phase shift each.... and if the
is driven by a sinusoidal input... then, you could use the Tektronix unit
to
determine the overall RMS output, of the cascaded system.
Since, the RMS values of the inputs to each subsystem are
orthogonal...because
of the phase shift.
And RMSout = sqrt( RMS1^2 + RMS2^2 + RMS3^2 )
Best regards and wishes.
Roy
P.S. You might have meant, why the circuit with do that above
calculation...
or any other calculations. If so, see the other posts in this thread, for
an
explanation.

Re: MEMBERS PLEASE READ: Our annual Group.io payment is due in 2 weeks.

Thomas Dodge

Thanks for letting me know. I do actually have a few scopes. I have a
Tektronix 533 which doesn't work yet. It would be cool to get advice on
fixing it. I also have a Tektronix 7000 series scope. And I have a TDS 684
which I discovered at an electronics parts place, and it works very well.
Thanks for the email.

Tom

On Wed, Jan 15, 2020, 10:07 PM Dennis Tillman W7PF <dennis@ridesoft.com>
wrote:

Hi Tom,
If you haven't noticed it until now it is safe to ignore it.
Sorry if that confused you.
Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of
Thomas Dodge
Sent: Wednesday, January 15, 2020 9:30 PM
To: TekScopes@groups.io
is due in 2 weeks.

Hi,
I don't know why I am getting this email. I never paid anything before.

Tom Dodge

On Mon, Dec 30, 2019 at 7:42 PM Dennis Tillman W7PF <dennis@ridesoft.com>
wrote:

Hello everybody,
In a few minutes it will be 2020. This is much further into the future
than I thought I'd ever see. Years ago I was sure someone would have
developed a tiny ultra-thin LED display that can be imbedded into a
credit card by 2020.
It would display your current outstanding balance every time the card
was inserted in a reader. If my non-futuristic credit cards only had
this imbedded into them I would certainly not be in my present
predicament. I maxed out both cards and my wife took them away. I
found this puzzling because the cards still look the same even though
they don't work anymore.
It is clear to her that she can't afford to keep me. She has made this
very clear to me often in the past 2 weeks.

Since we moved to Groups.io I have been paying the annual fee they
charge to host us. I did this for two reasons:
* It was expedient when we first joined because the demise of Yahoo
seemed imminent and this was the fastest way to get up and running on
Groups.io.
* Later when I asked for suggestions on alternate ways to pay for
Groups.io I didn't see anything I liked. I thank you for all of them,
they were all fine. It seemed as if they would create extra work and,
more importantly, consume more of my time (which is in very short
supply). I kept each of your suggestions for future consideration.

In 2 weeks the total amount I will have paid will be \$340. This is
significant enough that I have to do something about it, and more
importantly, I need to get back into my wife's good graces. So I am
asking for small contributions via PayPal if possible to be sent to
dennis@ridesoft.com. If you include a note along with each
contribution saying it is for Groups.io that will make it easier to
track. See the postscript at the end of my post for a no-fee way to
send money with PayPal.

If PayPal doesn't work for you my address is 13808 NE 26th Place,
Bellevue, WA 98005 USA. If you have an extremely rare or unusual 7000
series plugin that is definitely an acceptable form of payment but I
must advise you I probably already have it so contact me first.

I plan to give an accounting of the total to the group once the
contributions stop. Anything over \$340 will be set aside. I will find
out if Groups.io will let me pay for the following year (or years) so
we don't have to worry if I get hit by a truck. I will press them hard
to let me do this at the old price of \$110/yr.

This is the Groups.io billing summary for TekScopes:
Invoice Date Plan Payment Method
Amount Paid By
#3055 01/13/19 Premium Visa XXXX XXXX XXXX 7319 USD \$110
dennis@ridesoft.com
#814 01/13/18 Premium Visa XXXX XXXX XXXX 7319 USD \$110
dennis@ridesoft.com
#793 12/13/17 Premium Visa XXXX XXXX XXXX 7319 USD \$10
dennis@ridesoft.com
The next payment of \$110 is due 01/13/2000. NOTE: It appears the
annual price for the Premium Yearly Plan will go up the first of the
year to \$220.

Dennis Tillman W7PF

P.S. This is a way to send money via PayPal with minimal or no fee:
NO FEE PAYMENT METHOD FOR USA TEKSCOPES MEMBERS
* Choose "Send and Request".
* By default the Send tab will be chosen for you.
* In the "Send Money" field enter dennis@ridesoft.com.
* Next PayPal will ask you: "Sending to a Friend" or "Paying for an
invoice or service"?
* Choose "Sending to a friend".
* Enter the amount.
* Press next and choose your bank account to avoid the PayPal fee.
* Press the "Send the Money" button.
MINIMAL FEE PAYMENT FOR FOREIGN TEKSCOPES MEMBERS
* Chose "Send to friends and family internationally".
* Select the country you are sending to (USA).
* To keep the fee to 1% where it says "Select your delivery method"
choose "Send to a PayPal Balance".
* Under "You Send", enter whatever amount in local currency converts
to the correct US currency.
* Press next.
* The email account you will be sending to is dennis@ridesoft.com.
I can't help you after this point in PayPal because I was not outside
the USA to see what happened next.

--
Dennis Tillman W7PF
TekScopes Moderator

--
Dennis Tillman W7PF
TekScopes Moderator

Re: Using U-ship for shipping scopes?

Greg Muir

Simply Google “U-Ship reviews” and look at what comes up. A quick look that I took appears that it may be a broker who contracts out the jobs for anything from smaller items to cars & boats. That is, unless there are other U-Ship concerns operating with the same name. I did notice that there are several complaints about the packages taking weeks for delivery.

Speaking of slow delivery, I recently experienced a few instances where items I purchased were sent by another off-brand carrier that took a couple of weeks. Tracking each package (aside from when the information was mostly not available) showed them being shipped from the sender on the east coast to the Midwest the further south in the Midwest before apparently being staged at some warehouse for a week. They then passed once through my state on their way to Las Vegas then back through Denver and into my state again. That took another week and a half for delivery. From what I can tell the carrier was a cheap rate package aggregator who had certain locations where they collected packages until they had a full load then moving them on to their next staging location. Ultimately they were handed over to Fed-X for delivery when they got closer to my location. Of course this meant the packages being transported for more distance than necessary and obviously more vibration forces on the contents.

Like any other shipping carrier even occasionally including the “big boys” you take your chances unless you do the packing if the instrument yourself making sure that it is adequately padded and protected. Personally I don’t even trust the local UPS Store after watching them pack heavy items in squishy packaging that makes the container like a pillow and subject to easier tearing and other damage. Every heavy item that I pack is double boxed with closed cell foam cushions between the containers on top of the internal box cushioning for the enclosed item.

Greg

Re: MEMBERS PLEASE READ: Our annual Group.io payment is due in 2 weeks.

Harvey White

If you copy the one in blue, you may be including the hidden characters that control the color.  This confuses the heck out of your email program.

Harvey

On 1/17/2020 9:42 AM, Lawrance A. Schneider wrote:
Same happens to me.
further, what it the difference between @Dennis_Tillman_W&PF and the same thing in blue??? I saw a missive saying to use the above in blue and the same thing in black. I again tried each at PayPal and got the same thing asking for an :an error saying please enter valid email, name or mobile phone m=number.
I know I'm getting old, but what is going on???????

larry

Re: Risetime calculator (in tekwiki)

Harvey White

Perhaps I can help a bit.

Look at some of the sliderule scales if you can.  If you wanted to do addition, the scales would be linear.  If you wanted to do multiplication, they would not be.  You move the slides and 2*2 aligns with 4.  4*4 aligns with 16.  If you had pots, then while the pots can be linear, and you may or may not compute each step as if it were linear (and you probably wouldn't), when you balance the bridge, you want the final pot to read a value that's the result of the equation.

in other words, if you have 1 and 1, the result scale needs to balance at 1.  If you have 2 and 2, the result scale needs to balance at 1.414 * 2, or 2.828.  Mark that value as 2.828.  You have to balance the two legs to an equal voltage.  Even if the pots are linear, you mark them with the appropriate scale values to solve the equation.

Harvey

On 1/17/2020 10:48 PM, amirb wrote:
Roy
sorry my mistake, I only meant why/how this thing can calculate square root of sum of squares (should not have used rms for that perhaps)
obviously there are no sinusoidal voltages or anything like that in this device.

and so far nobody here knows exactly how this device works. Yes it is based on a bridge that when balanced you can read the answer on the
4th pot, That operation was pretty obvious by looking at the front panel. It appears to only have bunch of resistors (5 pots for calibration and 4 on the front panel plus
bunch of fixed resistors) and yet it does a nonlinear calculation or at least approximates a nonlinear expression that involves square root, but how?
nobody has explained that really.

It seems that it must be balancing the power in one resistor (4th pot) with the sum of powers in three other resistors!
but I have not seen a bridge that can do this...

I tried to draw the schematics by looking at that picture but I got lost in the middle of it...

On Fri, Jan 17, 2020 at 08:50 PM, Roy Thistle wrote:

On Fri, Jan 17, 2020 at 07:57 AM, amirb wrote:

why it will produce RMS
Hi amirb, et. al.:
If by RMS you mean "root mean square" … and if there are three cascaded
systems with, for example, 90 degree phase shift each.... and if the cascade
is driven by a sinusoidal input... then, you could use the Tektronix unit to
determine the overall RMS output, of the cascaded system.
Since, the RMS values of the inputs to each subsystem are orthogonal...because
of the phase shift.
And RMSout = sqrt( RMS1^2 + RMS2^2 + RMS3^2 )
Best regards and wishes.
Roy
P.S. You might have meant, why the circuit with do that above calculation...
or any other calculations. If so, see the other posts in this thread, for an
explanation.

Re: Risetime calculator (in tekwiki)

amirb

Roy
sorry my mistake, I only meant why/how this thing can calculate square root of sum of squares (should not have used rms for that perhaps)
obviously there are no sinusoidal voltages or anything like that in this device.

and so far nobody here knows exactly how this device works. Yes it is based on a bridge that when balanced you can read the answer on the
4th pot, That operation was pretty obvious by looking at the front panel. It appears to only have bunch of resistors (5 pots for calibration and 4 on the front panel plus
bunch of fixed resistors) and yet it does a nonlinear calculation or at least approximates a nonlinear expression that involves square root, but how?
nobody has explained that really.

It seems that it must be balancing the power in one resistor (4th pot) with the sum of powers in three other resistors!
but I have not seen a bridge that can do this...

I tried to draw the schematics by looking at that picture but I got lost in the middle of it...

On Fri, Jan 17, 2020 at 08:50 PM, Roy Thistle wrote:

On Fri, Jan 17, 2020 at 07:57 AM, amirb wrote:

why it will produce RMS
Hi amirb, et. al.:
If by RMS you mean "root mean square" … and if there are three cascaded
systems with, for example, 90 degree phase shift each.... and if the cascade
is driven by a sinusoidal input... then, you could use the Tektronix unit to
determine the overall RMS output, of the cascaded system.
Since, the RMS values of the inputs to each subsystem are orthogonal...because
of the phase shift.
And RMSout = sqrt( RMS1^2 + RMS2^2 + RMS3^2 )
Best regards and wishes.
Roy
P.S. You might have meant, why the circuit with do that above calculation...
or any other calculations. If so, see the other posts in this thread, for an
explanation.

Re: What Tektronix means to me

Harvey White

Software is a series of instructions to an idiot, which follows them as exactly as it can interpret them.

You need to understand what the instructions do.

You need to understand what the instructions were supposed to do.

You need to understand what the instructions REALLY do.

You need to understand the difference between the last two items.

and yes, you need to understand the instructions.

Harvey

On 1/17/2020 4:52 PM, Abc Xyz wrote:
"Eventually I became frustrated because I didn't understand software." ...
Sounds like me!

On Fri, Jan 17, 2020, 11:15 AM Jim Ford <james.ford@cox.net> wrote:

Crap, Dennis, now you make me want a 7854 even more! Fortunately I know
several people who will gladly sell me one when the time comes. Got to
satisfy my frequency domain cravings first.I'm chuckling that HW jocks
would fear the internal Tek SW language! The one and only time I wrote
software for a living was the summer of 1987 when I worked in a medical
research lab at CWRU. They had an Apple ][ with 8 inch floppy drives, and
it was ancient even back then. Turns out Apple stored the program lines
just adjacent to the "hi-res" graphics page. So as I added features to the
data acquisition program I was writing, I got to the point where these
strange lines appeared on the screen! A different way of collapsing under
its own weight! And one sure way to curtail scope creep.Great
story!JimSent from my Verizon, Samsung Galaxy smartphone
-------- Original message --------From: Dennis Tillman W7PF <
dennis@ridesoft.com> Date: 1/16/20 3:36 PM (GMT-08:00) To:
TekScopes@groups.io Subject: Re: [TekScopes] What Tektronix means to me
The 7854 is both analog (400MHz) and digital. It combines the best of both
worlds.As the very first digital lab scope they did many things that were
ground breaking. Start with the fact that the 7000 series was designed
before the concept of digital scopes could even have be conceived of. It
would have been understandable if the already released 7000 plugins were
not compatible with it but they all work just fine. The 7854 design team
chose to use 10-bit samples when everyone else settled on 8-bits because it
was more efficient and less complicated. 10-bit samples make for a much
SMOOTHER display of stored traces. It has an astounding vector processing
software language built into it that terrified hardware EEs. Tek quickly
removed any reference to it from their marketing materials when they got
of all hardware engineers viewed programming as black magic. This built in
language for processing waveforms was revolutionary. It is unfortunate that
this was developed decades before engineers were willing and able to use
anything like it. It was the first scope with a GPIB interface so you could
talk to it. I wrote an extensive program in 1993 in MSDOS Quick Basic that
allowed me to do anything I wanted with my 7854. It took advantage of the
GPIB interface to read and store waveforms on disk or to write waveforms
back to the 7854 for later display. I wrote programs using the external
keyboard and ran the programs on the 7854 or saved them for later use on
disk. I could write 20 lines of text on the 7854 CRT. My software
automatically calculated and displayed dozens of parameters about any
waveform I captured and displayed them on my PC monitor alongside the
waveform. As do most BASIC programs it eventually grew so complicated it
collapsed under its own weight when I could no longer keep track of the
interactions between different sections of it.Since I knew you would ask
what did the results looks like I put six waveforms I captured with it (and
all the parameters it calculated) up on TekScopes photo section. They are
in: https://groups.io/g/TekScopes/album?id=238613Dennis Tillman
W7PF-----Original Message-----From: TekScopes@groups.io [mailto:
TekScopes@groups.io] On Behalf Of Abc XyzSent: Thursday, January 16, 2020
1:29 PMTo: TekScopes@groups.ioSubject: Re: [TekScopes] What Tektronix
means to meDennis, I'm curious...of all the Scopes you have been exposed to
you say the 7854 is your Favorite. Why is that? JROn Thu, Jan 16, 2020,
12:57 PM Dennis Tillman W7PF <dennis@ridesoft.com>wrote:> Hi Jim,> The
job offer letter from Tektronix is laminated on a plaque where it > sits on
my wall along side my diplomas. No. I never went to work at > Tek. But in a
way I got to become an honorary member of Tek.>> I have been embraced by
everyone I meet that is a current or ExTek > employee. I have been included
in their private mail reflector, I have > been a member of the vintageTEK
Museum since before it opened when > Stan Griffiths first took me over to
see the empty store front that > would soon be its first home.>> The
biggest surprise was when Michael Dunn asked me to take over as > moderator
of TekScopes. Why me?>> Usually 4 times a year I am in Beaverton visiting
my Tek friends. > Somehow one of the most famous design engineers at Tek
heard about me > several years ago and quite by accident I introduced
myself to him at > the museum. He replied "You're Dennis Tillman!" which
stunned me. He > is now one of my best friends. He is so highly regarded
among ex-Tek > employees that I will often call him to arrange a lunch with
someone > at Tek that was legendary. They never refuse. I have had many >
fascinating lunches with the people I might have known if I had become > a
Tek employee. We often met for lunch in the Tek cafeteria. Tek > closed the
cafeteria last month so I'm not sure where we will have those lunches
next.>> My favorite scope is the 7854. When I mentioned this to Deane Kidd
at > a swap meet one day he said the 7854 project manager was in the next >
room having a bite to eat and he introduced me to him. A few days > later I
asked him to autograph the cover of my 7854. He was puzzled > why I would
want his autograph.>> Asking for autographs was something I had started to
do when I was at > Microsoft. For each Software Developer Conference I held
I asked all > the speakers to autograph their section of the conference
notebooks. > Bill Gates and Steve Ballmer's signatures are in them as are
all the > Windows developers and many of the famous software developers of
the > mid-1980s that attended the conferences.>> By now that 7854 cover is
so full of autographs of ex-Tek employees > that I have had to switch to
the other cover. When I'm all done with > the covers I will give them to
the 7854 Project Manager who is now a > good friend of mine that I see
every time I'm at a swap meet.>> Dennis Tillman W7PF>> -----Original
Message-----> From: TekScopes@groups.io [mailto:TekScopes@groups.io] On
Behalf Of > Jim Ford> Sent: Thursday, January 16, 2020 6:48 AM> To:
TekScopes@groups.io> Subject: Re: [TekScopes] What Tektronix means to
me>> Hey, don't keep us in suspense, Dennis! Did you ever get to work for
Tek?Jim Ford Sent from my Verizon, Samsung Galaxy smartphone> --------
Original message --------From: Dennis Tillman W7PF < > dennis@ridesoft.com>
Date: 1/15/20 10:36 PM (GMT-08:00) To:> TekScopes@groups.io Subject:
Re: [TekScopes] What Tektronix means to > me Hi Harvey,Yes, there is no
simple solution to things being too far > away but saying "I never expect
to go there" (to the Tek Museum) is > not the best way to start out if your
goal is to get there. You never > know what you ae capable of until you
try. On more than one occasion I > decided to hitch hike cross country from
New Jersey to LA and up to > San Francisco. Along the way I stopped at the
St. Louis Gateway Arch, > Grand Canyon, Mt Palomar to see the telescope,
and the meteor crater > in Arizona. On another trip down to the Keys I
stopped at the new > Disney World in Orlando. I've been to Mardi Gras three
times.I had an > offer to join Tek in 1968 when I was starting my junior
year in > college. But they recommended that I get my degree first and
assured > me that the job would still be there when I did. Life took me in
a > different direction by the time I got my BS E.E. degree. For the next >
20 years I regretted that mistake. Instead I moved into a beach front >
apartment on the New Jersey shore and, to my surprise, I became a > stained
glass artist and beach comer and I went back to college, this > time for a
BA in Fine Arts. When I first heard it was possible to > build a computer
(a childhood dream of mine) I changed direction again > and began building
my own S-100 microcomputer. There were very few > people doing that so I
quickly found a job working on microcomputers. > Eventually I became
frustrated because I didn't understand software. > That became my next
challenge. Once I learned microcomputer > programming I thought it would be
smart to broaden my computer > background with some mainframe experience.
When I tried to do that I > found out very few head hunters even knew what
a microcomputer was. > They were focused on filling the thousands of jobs
available in the > mainframe world. So I spent the next 6 months trying to
get a mainframe job with no success. Eventually I was hired by an IBM 370
based time sharing company which saw there was an opportunity linking
microcomputers to mainframes.> That exposed me to IBM's premier operating
system: Multiple Virtual > Systems> (MVS) and the many different IBM
operating systems and applications > that worked under MVS. Three years
later someone recommended me for a > job with Digital Research, the creator
of CP/M (which I knew well), > the industry standard 8-bit OS on
microcomputers. Four years later > that led to a job at Microsoft which I
was desperate to get because it > would finally bring me to the Pacific
Northwest (Tektronix territory) > where I would have been 20 years earlier
if I had joined Tek. After 3 > years at Microsoft it became clear I had the
wrong background. They > had their pick of graduating students with an MS
in Computer Science > or an MBA. So I went back to college a third time for
an MS in > Software Engineering. While I was getting that degree, Microsoft
went > from 500 people which was small enough that I knew almost everyone
too > many thousands of people. I don't like big companies and there were >
other opportunities for me now that I had an MS S.E.If you are on the >
other side of the earth and looking at a very small map it may appear >
that Microsoft (a few miles from Seattle), and Tektronix (a few miles >
from Portland) are right next to each other. It is a boring 3> 1/2 hour
trip to get there. Sphere Research is more than twice as far. > On more
than one occasion I decided to hitch hike cross country from > New Jersey
to LA and up to San Francisco. Along the way I stopped at the St.> Louis
Gateway Arch, Grand Canyon, Mt Palomar (to see the telescope), > and the
meteor crater in Arizona. On another trip down to the Keys and > Key West I
stopped at the new Disney World in Orlando. I've been to > Mardi Gras three
times. You shouldn't say things like I never expect > to get there. It
sounds like you really want to go. If you can make it > to Seattle you have
a place to stay with us. Portland is a train ride > away. Beaverton is
accesable by light rail from Portland. Dennis > Tillman W7PF-----Original>
Message-----From: TekScopes@groups.io [mailto:TekScopes@groups.io] On >
Behalf Of Harvey WhiteSent: Wednesday, January 15, 2020 5:28 PMTo:>
TekScopes@groups.ioSubject: Re: [TekScopes] What Tektronix means to > meI
understand what you say, parallel to an extent, not congruent >
experiences.The Tek museum is 3000 miles from me, and I never expect > to
go there.Might we have something on the east coast?(and yes, I'm > annoyed
that Sphere's "free" days are even further fromme.) Still > would like to
find a> 214 vertical amplifier board because mine has a bad channel A >
attenuator, not that I've asked before.)HarveyOn 1/15/2020 5:15 PM, >
Dennis Tillman W7PF wrote:> Like everyone here I have created a > problem
my wife will have to deal with when I am no longer around. She > has the
phone number of the vintageTEK Museum on our refrigerator. > Problem
solved.>> Now that that's out of the way I'm not concerned > with recyclers
and what will come of my stuff. I plan on enjoying the > afterlife with a
Tek 214 portable dual-trace storage scope in my > coffin. The Egyptians had
the right idea. Take what you can with you > when you go.>> Tektronix gives
me a reason to get up every day. I can > explore anything in electronics
with the instruments they designed. I > am the beneficiary of the legacy of
Tektronix; the standard of > excellence they strove for; and the support
they provided for their products.>> IN 1967 I bought my first Tek scope, a
453, new for \$2,000.> What I learned in the next two years by using that
scope every night > propelled me to the top of my class. That was the best
investment I > ever made. Tektronix instruments were investments in my
future. 10 > years later I bought a 7704A / 7A26 / 7B80 / 7B85 and a pair
of P6106 probes for \$7,000.> I went into debt to do this because I knew it
would pay off for me > just like my 453 had. Two years later I bought a
7D01 / DF2 / DL2 for > another> \$4,000 to study microcomputers. I eagerly
learned microcomputer > assembly language to control the microcomputer
hardware I was > designing. The next 10 years I had a very rewarding career
in > microcomputers, mainframes, operating systems, and software >
marketing.>> Several totally unexpected things happened starting in > the
late 1990s that were to enrich my life yet again. EBay gave me a > way to
buy all of the Tektronix instruments I could never afford back > in the
1970s. In 2000 Michael Dunn started TekScopes and I joined 2 > years later.
Suddenly I was not alone. I had a vast resource of > expertise to help me
fix all the Tek instruments I was buying on eBay. > 10 years ago Stan
Griffiths and Ed Sinclair started the vintageTEK > Museum as a showcase for
all the things Tektronix had made possible.> The museum is preserving the
Tek legacy for the benefit of all of us. > Last but not least we have our
own specialized Wikipedia. TekWiki has > become THE professional repository
of Tektronix documents thanks to > the tireless work of Kurt Rosenfeld.
Working long hours alone, into > the night, feeding every Tek document he
can find into scanners. He > has single-handedly assembled those papers,
manuals, photographs, and > comments into a beautiful, easy to use, library
at our finger tips. > TekWiki is every bit that is the rival of
Wikipedia.>> I'm too busy > using my collection of Tek instruments to dwell
on what will happen to > it someday. Because of Tektronix, eBay, TekScopes,
the vintageTEK > museum, and TekWiki my life is never dull when a Tektronix
scope is > within arm's reach.>> Dennis Tillman W7PF>>>-- Dennis Tillman >
W7PFTekScopes Moderator>>>>>> --> Dennis Tillman W7PF> TekScopes
Moderator>> >>-- Dennis Tillman W7PFTekScopes Moderator

Using U-ship for shipping scopes?

Jamie Ostrowski

I was wondering if anyone has had any experience using uship.com for shipping scopes or other electronics. If you're unfamiliar with them, they are like an Uber, but for shipping, including long distances.

I heard about it watching a shango66's Youtube channel. In one episode someone had purchased an old tube television from him and had uship pick it up.

The guy came up in a minivan and put the TV inside, put a heavy blanket around it and treated it decently, and off it went. He mentioned he was taking the TV quite a distance - I think it was from California to Ohio if I recall.

I haven't tried using them yet, but I am curious if anyone else has. It seems like it might be a viable alternative to the other shipping giants and the equipment may be treated better, being packed in a van by one person rather than constantly tossed around.

Re: Risetime calculator (in tekwiki)

Hi Jason,
I have never seen one of these before the other day but I can reproduce the analog computer my friend and I made when we were in high school as a substitute until you find the Tektronix one. It had a beautiful Formica wood grain front panel to impress people. I can even put something that looks like a Tek logo on it. Let me know. :)
Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Jason A. via Groups.Io
Sent: Friday, January 17, 2020 12:31 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Risetime calculator (in tekwiki)

I would love to have one of those Tektronix Circuit Computers too! I've been watching for one to show up and have never found one yet. Jon, do you have a 3d printer? I bet you could make copies and sell them! :-) You probably wouldn't get rich doing so, but Like the VTCT Dennis came up with, you'd probably have more demand than either of us would have thought...

--
Dennis Tillman W7PF
TekScopes Moderator

Re: What Tektronix means to me

Hi Tam,
Sure, go ahead and post them as long you include attribution, meaning you say who did them.
Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Tam Hanna
Sent: Friday, January 17, 2020 12:15 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] What Tektronix means to me

Hello,

sorry - I wanted to write offline, but my provider again has problems delivering email to the US. Never go with a large provider, and avoid
1und1 or IONOS.

What I wanted to do was ask if I could post these pictures on my Instagram!

Tam

--
With best regards
Tam HANNA

Enjoy electronics? Join 15k7 other followers by visiting the Crazy Electronics Lab at https://www.instagram.com/tam.hanna/

--
Dennis Tillman W7PF
TekScopes Moderator

Re: Risetime calculator (in tekwiki)

Hi Barry,
I didn't thinking of telling that to Andrea, my friend's sister, at the time. I doubt she would have bought it.
Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of n4buq
Sent: Friday, January 17, 2020 9:01 AM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Risetime calculator (in tekwiki)

Sounds like the system had lost its calibration data; however, 2 x 3 does equal 8 for large values of 3.

Thanks,
Barry - N4BUQ

----- Original Message -----
From: "Dennis Tillman W7PF" <dennis@ridesoft.com>
To: TekScopes@groups.io
Sent: Friday, January 17, 2020 10:02:17 AM
Subject: Re: [TekScopes] Risetime calculator (in tekwiki)

Hi Tim,
When I was in high school my friend and I built an analog computer
with 2 pots and a meter. It multiplied two numbers together and
displayed the result on the meter.
When we showed it to my friend's sister she asked us to multiply 2x3.
The result we got was around 8 on the meter. It could have been 9 or
7. It was hard to tell.
She was not impressed.

We looked around for something better to do with our budding career in
electronics.
There wasn't much. The only "instrument" I owned was a VTVM. That

Dennis Tillman W7PF

--
Dennis Tillman W7PF
TekScopes Moderator

Re: Risetime calculator (in tekwiki)

Roy Thistle

On Fri, Jan 17, 2020 at 07:57 AM, amirb wrote:

why it will produce RMS
Hi amirb, et. al.:
If by RMS you mean "root mean square" … and if there are three cascaded systems with, for example, 90 degree phase shift each.... and if the cascade is driven by a sinusoidal input... then, you could use the Tektronix unit to determine the overall RMS output, of the cascaded system.
Since, the RMS values of the inputs to each subsystem are orthogonal...because of the phase shift.
And RMSout = sqrt( RMS1^2 + RMS2^2 + RMS3^2 )
Best regards and wishes.
Roy
P.S. You might have meant, why the circuit with do that above calculation... or any other calculations. If so, see the other posts in this thread, for an explanation.

Re: Risetime calculator (in tekwiki)

Roy Thistle

On Fri, Jan 17, 2020 at 03:30 AM, GerryR wrote:

How is it used to calculate rise time?
Hi GerryR, Hi All:
If I remember correctly....
If T = the total rise time of a cascaded system, and
ti for I = 1 to n is the rise time for each of the n subsystems, of the cascaded system.
then, for n =3, as for example in the Tektronix unit
T = sqrt( t1^2 + t2^2 + t3^2 )
so the unit computes the overall risetime of a cascaded system, supposing you know the rise times of the three cascaded systems.
Doing it with a slide rule requires finding three squares on the slide rule, 3 copies, two hand additions, and a final square root operation on the slide rule... versus 4 operations on the Tektronix unit. I'd rather use the Tektronix unit... and unless there was a large, very well made, slide rule available, the Tektronix unit was probably as accurate for the final result... or the answers it gave were good enough.
Best wishes and regards.
Roy

Re: What Tektronix means to me

Abc Xyz

"Eventually I became frustrated because I didn't understand software." ...
Sounds like me!

On Fri, Jan 17, 2020, 11:15 AM Jim Ford <james.ford@cox.net> wrote:

Crap, Dennis, now you make me want a 7854 even more! Fortunately I know
several people who will gladly sell me one when the time comes. Got to
satisfy my frequency domain cravings first.I'm chuckling that HW jocks
would fear the internal Tek SW language! The one and only time I wrote
software for a living was the summer of 1987 when I worked in a medical
research lab at CWRU. They had an Apple ][ with 8 inch floppy drives, and
it was ancient even back then. Turns out Apple stored the program lines
just adjacent to the "hi-res" graphics page. So as I added features to the
data acquisition program I was writing, I got to the point where these
strange lines appeared on the screen! A different way of collapsing under
its own weight! And one sure way to curtail scope creep.Great
story!JimSent from my Verizon, Samsung Galaxy smartphone
-------- Original message --------From: Dennis Tillman W7PF <
dennis@ridesoft.com> Date: 1/16/20 3:36 PM (GMT-08:00) To:
TekScopes@groups.io Subject: Re: [TekScopes] What Tektronix means to me
The 7854 is both analog (400MHz) and digital. It combines the best of both
worlds.As the very first digital lab scope they did many things that were
ground breaking. Start with the fact that the 7000 series was designed
before the concept of digital scopes could even have be conceived of. It
would have been understandable if the already released 7000 plugins were
not compatible with it but they all work just fine. The 7854 design team
chose to use 10-bit samples when everyone else settled on 8-bits because it
was more efficient and less complicated. 10-bit samples make for a much
SMOOTHER display of stored traces. It has an astounding vector processing
software language built into it that terrified hardware EEs. Tek quickly
removed any reference to it from their marketing materials when they got
of all hardware engineers viewed programming as black magic. This built in
language for processing waveforms was revolutionary. It is unfortunate that
this was developed decades before engineers were willing and able to use
anything like it. It was the first scope with a GPIB interface so you could
talk to it. I wrote an extensive program in 1993 in MSDOS Quick Basic that
allowed me to do anything I wanted with my 7854. It took advantage of the
GPIB interface to read and store waveforms on disk or to write waveforms
back to the 7854 for later display. I wrote programs using the external
keyboard and ran the programs on the 7854 or saved them for later use on
disk. I could write 20 lines of text on the 7854 CRT. My software
automatically calculated and displayed dozens of parameters about any
waveform I captured and displayed them on my PC monitor alongside the
waveform. As do most BASIC programs it eventually grew so complicated it
collapsed under its own weight when I could no longer keep track of the
interactions between different sections of it.Since I knew you would ask
what did the results looks like I put six waveforms I captured with it (and
all the parameters it calculated) up on TekScopes photo section. They are
in: https://groups.io/g/TekScopes/album?id=238613Dennis Tillman
W7PF-----Original Message-----From: TekScopes@groups.io [mailto:
TekScopes@groups.io] On Behalf Of Abc XyzSent: Thursday, January 16, 2020
1:29 PMTo: TekScopes@groups.ioSubject: Re: [TekScopes] What Tektronix
means to meDennis, I'm curious...of all the Scopes you have been exposed to
you say the 7854 is your Favorite. Why is that? JROn Thu, Jan 16, 2020,
12:57 PM Dennis Tillman W7PF <dennis@ridesoft.com>wrote:> Hi Jim,> The
job offer letter from Tektronix is laminated on a plaque where it > sits on
my wall along side my diplomas. No. I never went to work at > Tek. But in a
way I got to become an honorary member of Tek.>> I have been embraced by
everyone I meet that is a current or ExTek > employee. I have been included
in their private mail reflector, I have > been a member of the vintageTEK
Museum since before it opened when > Stan Griffiths first took me over to
see the empty store front that > would soon be its first home.>> The
biggest surprise was when Michael Dunn asked me to take over as > moderator
of TekScopes. Why me?>> Usually 4 times a year I am in Beaverton visiting
my Tek friends. > Somehow one of the most famous design engineers at Tek
heard about me > several years ago and quite by accident I introduced
myself to him at > the museum. He replied "You're Dennis Tillman!" which
stunned me. He > is now one of my best friends. He is so highly regarded
among ex-Tek > employees that I will often call him to arrange a lunch with
someone > at Tek that was legendary. They never refuse. I have had many >
fascinating lunches with the people I might have known if I had become > a
Tek employee. We often met for lunch in the Tek cafeteria. Tek > closed the
cafeteria last month so I'm not sure where we will have those lunches
next.>> My favorite scope is the 7854. When I mentioned this to Deane Kidd
at > a swap meet one day he said the 7854 project manager was in the next >
room having a bite to eat and he introduced me to him. A few days > later I
asked him to autograph the cover of my 7854. He was puzzled > why I would
want his autograph.>> Asking for autographs was something I had started to
do when I was at > Microsoft. For each Software Developer Conference I held
I asked all > the speakers to autograph their section of the conference
notebooks. > Bill Gates and Steve Ballmer's signatures are in them as are
all the > Windows developers and many of the famous software developers of
the > mid-1980s that attended the conferences.>> By now that 7854 cover is
so full of autographs of ex-Tek employees > that I have had to switch to
the other cover. When I'm all done with > the covers I will give them to
the 7854 Project Manager who is now a > good friend of mine that I see
every time I'm at a swap meet.>> Dennis Tillman W7PF>> -----Original
Message-----> From: TekScopes@groups.io [mailto:TekScopes@groups.io] On
Behalf Of > Jim Ford> Sent: Thursday, January 16, 2020 6:48 AM> To:
TekScopes@groups.io> Subject: Re: [TekScopes] What Tektronix means to
me>> Hey, don't keep us in suspense, Dennis! Did you ever get to work for
Tek?Jim Ford Sent from my Verizon, Samsung Galaxy smartphone> --------
Original message --------From: Dennis Tillman W7PF < > dennis@ridesoft.com>
Date: 1/15/20 10:36 PM (GMT-08:00) To:> TekScopes@groups.io Subject:
Re: [TekScopes] What Tektronix means to > me Hi Harvey,Yes, there is no
simple solution to things being too far > away but saying "I never expect
to go there" (to the Tek Museum) is > not the best way to start out if your
goal is to get there. You never > know what you ae capable of until you
try. On more than one occasion I > decided to hitch hike cross country from
New Jersey to LA and up to > San Francisco. Along the way I stopped at the
St. Louis Gateway Arch, > Grand Canyon, Mt Palomar to see the telescope,
and the meteor crater > in Arizona. On another trip down to the Keys I
stopped at the new > Disney World in Orlando. I've been to Mardi Gras three
times.I had an > offer to join Tek in 1968 when I was starting my junior
year in > college. But they recommended that I get my degree first and
assured > me that the job would still be there when I did. Life took me in
a > different direction by the time I got my BS E.E. degree. For the next >
20 years I regretted that mistake. Instead I moved into a beach front >
apartment on the New Jersey shore and, to my surprise, I became a > stained
glass artist and beach comer and I went back to college, this > time for a
BA in Fine Arts. When I first heard it was possible to > build a computer
(a childhood dream of mine) I changed direction again > and began building
my own S-100 microcomputer. There were very few > people doing that so I
quickly found a job working on microcomputers. > Eventually I became
frustrated because I didn't understand software. > That became my next
challenge. Once I learned microcomputer > programming I thought it would be
smart to broaden my computer > background with some mainframe experience.
When I tried to do that I > found out very few head hunters even knew what
a microcomputer was. > They were focused on filling the thousands of jobs
available in the > mainframe world. So I spent the next 6 months trying to
get a mainframe job with no success. Eventually I was hired by an IBM 370
based time sharing company which saw there was an opportunity linking
microcomputers to mainframes.> That exposed me to IBM's premier operating
system: Multiple Virtual > Systems> (MVS) and the many different IBM
operating systems and applications > that worked under MVS. Three years
later someone recommended me for a > job with Digital Research, the creator
of CP/M (which I knew well), > the industry standard 8-bit OS on
microcomputers. Four years later > that led to a job at Microsoft which I
was desperate to get because it > would finally bring me to the Pacific
Northwest (Tektronix territory) > where I would have been 20 years earlier
if I had joined Tek. After 3 > years at Microsoft it became clear I had the
wrong background. They > had their pick of graduating students with an MS
in Computer Science > or an MBA. So I went back to college a third time for
an MS in > Software Engineering. While I was getting that degree, Microsoft
went > from 500 people which was small enough that I knew almost everyone
too > many thousands of people. I don't like big companies and there were >
other opportunities for me now that I had an MS S.E.If you are on the >
other side of the earth and looking at a very small map it may appear >
that Microsoft (a few miles from Seattle), and Tektronix (a few miles >
from Portland) are right next to each other. It is a boring 3> 1/2 hour
trip to get there. Sphere Research is more than twice as far. > On more
than one occasion I decided to hitch hike cross country from > New Jersey
to LA and up to San Francisco. Along the way I stopped at the St.> Louis
Gateway Arch, Grand Canyon, Mt Palomar (to see the telescope), > and the
meteor crater in Arizona. On another trip down to the Keys and > Key West I
stopped at the new Disney World in Orlando. I've been to > Mardi Gras three
times. You shouldn't say things like I never expect > to get there. It
sounds like you really want to go. If you can make it > to Seattle you have
a place to stay with us. Portland is a train ride > away. Beaverton is
accesable by light rail from Portland. Dennis > Tillman W7PF-----Original>
Message-----From: TekScopes@groups.io [mailto:TekScopes@groups.io] On >
Behalf Of Harvey WhiteSent: Wednesday, January 15, 2020 5:28 PMTo:>
TekScopes@groups.ioSubject: Re: [TekScopes] What Tektronix means to > meI
understand what you say, parallel to an extent, not congruent >
experiences.The Tek museum is 3000 miles from me, and I never expect > to
go there.Might we have something on the east coast?(and yes, I'm > annoyed
that Sphere's "free" days are even further fromme.) Still > would like to
find a> 214 vertical amplifier board because mine has a bad channel A >
attenuator, not that I've asked before.)HarveyOn 1/15/2020 5:15 PM, >
Dennis Tillman W7PF wrote:> Like everyone here I have created a > problem
my wife will have to deal with when I am no longer around. She > has the
phone number of the vintageTEK Museum on our refrigerator. > Problem
solved.>> Now that that's out of the way I'm not concerned > with recyclers
and what will come of my stuff. I plan on enjoying the > afterlife with a
Tek 214 portable dual-trace storage scope in my > coffin. The Egyptians had
the right idea. Take what you can with you > when you go.>> Tektronix gives
me a reason to get up every day. I can > explore anything in electronics
with the instruments they designed. I > am the beneficiary of the legacy of
Tektronix; the standard of > excellence they strove for; and the support
they provided for their products.>> IN 1967 I bought my first Tek scope, a
453, new for \$2,000.> What I learned in the next two years by using that
scope every night > propelled me to the top of my class. That was the best
investment I > ever made. Tektronix instruments were investments in my
future. 10 > years later I bought a 7704A / 7A26 / 7B80 / 7B85 and a pair
of P6106 probes for \$7,000.> I went into debt to do this because I knew it
would pay off for me > just like my 453 had. Two years later I bought a
7D01 / DF2 / DL2 for > another> \$4,000 to study microcomputers. I eagerly
learned microcomputer > assembly language to control the microcomputer
hardware I was > designing. The next 10 years I had a very rewarding career
in > microcomputers, mainframes, operating systems, and software >
marketing.>> Several totally unexpected things happened starting in > the
late 1990s that were to enrich my life yet again. EBay gave me a > way to
buy all of the Tektronix instruments I could never afford back > in the
1970s. In 2000 Michael Dunn started TekScopes and I joined 2 > years later.
Suddenly I was not alone. I had a vast resource of > expertise to help me
fix all the Tek instruments I was buying on eBay. > 10 years ago Stan
Griffiths and Ed Sinclair started the vintageTEK > Museum as a showcase for
all the things Tektronix had made possible.> The museum is preserving the
Tek legacy for the benefit of all of us. > Last but not least we have our
own specialized Wikipedia. TekWiki has > become THE professional repository
of Tektronix documents thanks to > the tireless work of Kurt Rosenfeld.
Working long hours alone, into > the night, feeding every Tek document he
can find into scanners. He > has single-handedly assembled those papers,
manuals, photographs, and > comments into a beautiful, easy to use, library
at our finger tips. > TekWiki is every bit that is the rival of
Wikipedia.>> I'm too busy > using my collection of Tek instruments to dwell
on what will happen to > it someday. Because of Tektronix, eBay, TekScopes,
the vintageTEK > museum, and TekWiki my life is never dull when a Tektronix
scope is > within arm's reach.>> Dennis Tillman W7PF>>>-- Dennis Tillman >
W7PFTekScopes Moderator>>>>>> --> Dennis Tillman W7PF> TekScopes
Moderator>> >>-- Dennis Tillman W7PFTekScopes Moderator

Re: 7A26 transient response 5 nS all atten

John

My manual has a slip stating it was printed March 1981. Rev. letters vary across the sheets. There is a split of schematics & comp. locs. at S/n B180000 up.
155-0078-xx IC's appear with 01, 03, 05,07, 10 and 13 subscripts according to position and serial numbers. U2450 has four variants.
John

Re: Remote CSA803 / HP1180x programming (yet again)

Jim Ford

Somebody once said it stood for "I've Been Moved".My own employer, Raytheon, stands for "Reorganize All Year Then Hope Everything Operates Normally"!Jim Ford (Yes, I know what Ford stands for; I can think of at least 4 things)Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------From: Roy Morgan <k1lky68@gmail.com> Date: 1/17/20 2:59 AM (GMT-08:00) To: TekScopes@groups.io Subject: Re: [TekScopes] Remote CSA803 / HP1180x programming (yet again) Leo,I do remember Hays modem commands, though only dimly. I wonder if "AT" stands for "Attention, Terminal ! ". On a related bit of lore: while I  worked at NIST, I used a bit of SQL and learned that the letters originally stood for Structured Query Language but that later the official name of the standard was changed to "Database Language SQL", with no meaning for the letters.  Among my coworkers were the folks who organized and chaired the international committees that wrote the standards. (One fellow had chaired the committee that developed RS-232.)IBM used to mean "International Business Machines" didn't it?And so we "Graybeards" mumble off into the mists of time. ... ...Roy MorganK1LKY Western Mass> On Jan 17, 2020, at 4:31 AM, Leo Bodnar <leo@leobodnar.com> wrote:...> If you are old enough - think modems Hayes AT commands.> ...

Re: Risetime calculator (in tekwiki)

Jason A.

I would love to have one of those Tektronix Circuit Computers too! I've been watching for one to show up and have never found one yet. Jon, do you have a 3d printer? I bet you could make copies and sell them! :-) You probably wouldn't get rich doing so, but Like the VTCT Dennis came up with, you'd probably have more demand than either of us would have thought...

Re: What Tektronix means to me

Tam Hanna

Hello,

sorry - I wanted to write offline, but my provider again has problems delivering email to the US. Never go with a large provider, and avoid 1und1 or IONOS.

What I wanted to do was ask if I could post these pictures on my Instagram!

Tam

--
With best regards
Tam HANNA

Enjoy electronics? Join 15k7 other followers by visiting the Crazy Electronics Lab at https://www.instagram.com/tam.hanna/

Re: 7A26 transient response 5 nS all atten

Albert Otten

Hi Jon,
Anyone with a link or scan of the -01 Rev SEP 1985
You might ask Dave at ArtekManuals.com which Rev his 070-1484-01 pdf is.
I mentioned SEP 1985 since that's the one I have (also one of OCT 1987). Perhaps DEC 1984 or even APR 1984 already mentions your board versions.
I'm afraid a paper manual posted to you might never arrive because of all those strikes in Paris ;=)

Albert

Re: What Tektronix means to me

Jim Ford

Crap, Dennis, now you make me want a 7854 even more!  Fortunately I know several people who will gladly sell me one when the time comes.  Got to satisfy my frequency domain cravings first.I'm chuckling that HW jocks would fear the internal Tek SW language!  The one and only time I wrote software for a living was the summer of 1987 when I worked in a medical research lab at CWRU.  They had an Apple ][ with 8 inch floppy drives, and it was ancient even back then.  Turns out Apple stored the program lines just adjacent to the "hi-res" graphics page.  So as I added features to the data acquisition program I was writing, I got to the point where these strange lines appeared on the screen!  A different way of collapsing under its own weight!  And one sure way to curtail scope creep.Great story!JimSent from my Verizon, Samsung Galaxy smartphone