Date   

Re: TDS3000B calibration

 

Why would they say 100Hz to 1MHz if 100Hz to 10MHz would also work?
Maybe because there were none that went to 10MHz at that time - a bit like a laptop I own whose docs say it will take a maximum of 4GB, but will happily take 8GB.

David


Re: TDS3000B calibration

benj3867
 

On Wed, Mar 25, 2020 at 12:43 AM, amirb wrote:


for fast rise pulser, is it possible to use one of Leo Bodnar's? is the
frequency really important?
As far as I know, the Leo Bodnar pulser operates at 10MHz which is way too fast.
The TDS3000B service manual says that the frequency should be in the range of 100Hz to 1MHz. Why would they say 100Hz to 1MHz if 100Hz to 10MHz would also work?

While the Bodnar pulser would have been perfectly fine if you were to manually check the rise time of the scope, it will almost certainly not work in the calibration process which is automatic and during which the user can not adjust anything on the scope.

BTW, a suitable fast rise pulse generator can be easily built at home following the instructions in appendix D of Linear Technology Application Note 47 by Jim Williams (easily found on the web). All you need are 3 resistors, a capacitor, and a 2N2369 transistor. You also need a very low-current 90V power supply, which you can either build using an LT1073 as shown in the same article, or simply get from your friendly local *Bay (about $5 for a "DC-DC 8-32V to 45~390V High Voltage Boost Converter").


Re: TEKTRONIX 491 measuring wifi signals

Renée
 

geez Ernesto, seems along my thoughts---I wonder how many here are/were professional musicians???....myself an upper woodwind specialist, still working.....well not in this current environment....back to making oboe reeds.....and fixing my 2710 that was given to me. I wish it had the tracking gen battery made a mess........however,
I am happy with my 475 (200Mhz) ...although someday a 500Mhz would be nice ( think 7000 main frame or a 485).
Renée

On 3/24/20 9:03 PM, Ernesto wrote:
By the way, this high bandwidth scope I mentioned, the tektronix DPO70000SX, can sample at 200 Giga-samples/sec, with 5 pico-second sample resolution. And the price of this instrument with asynchronous time interleaving, ATI, starts at a mere $315,000.00 I know, it leaves my beloved 547 in the dust! But... I seldom need to measure anything with a 5 pico-second resolution. I enjoy the most with audio signals, ultrasound and signals up to the low RF frequencies.*If someone were to give me one as a present, I would sell it promptly and with the money buy a Fazioli concert grand piano.*


Re: Tek Blue Paint

ArtekManuals <manuals@...>
 

A couple of points about this comment (which is very valid)

1) Paint that is 40 years old versus a shade today will have aged differently  due to underlying formulation aging characteristics, time and UV exposure. A paint job that matches today may not match 10 years from now due to different aging characteristics of the two paints. If your really OCD about paint jobs you should paint the whole thing so that you don't have a mismatch due to differences in aging characteristics

2) (both) of my wives were artist and my brother in-law who was a (color blind) engineer for Bausch and Lomb  for 20+years will all tell you that the structure in our eyes are different from person to person and that we do not all see given colors in the same hue. What you may have heard of as "rods and cones" in our eyes for color vision are actually resonant structures not unlike what we are used to thinking about in microwaves . So while a given touch up may look perfect to me to another person it may look like a giant zit

Have fun ...me I stopped worrying about the color of things 35 years ago

Dave
manuals@artekmanuals.com

On 3/25/2020 9:20 AM, Bert Haskins wrote:

On 3/23/2020 11:11 PM, Brendan via Groups.Io wrote:
The closest I have been able to come is Bahama Sea by Krylon.
I bought some of this for my 22xx scopes and it is way off, at least for matching.

- Bert



--
Dave
Manuals@ArtekManuals.com
www.ArtekManuals.com
--
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus


Re: Tek Blue Paint

kim.herron@sbcglobal.net
 

Good info Reed. Just one minor point. Which company
did you have this paint mixed at? Is this
Sherwin-Williams? IF it is, that same paint mix code
should work at a NAPA auto store or anyone else that
has Martin-Senour as they are the same company. I've
done this same thing with Collins and Johnson transmitter
cabinet and face panels. Sherwin Williams still has their
OPEX machine lacquer available and the shine of the
finished sprayed product matches exact. You usually
have to get at least ONE gallon and it ain't cheap

On 24 Mar 2020 at 21:28, Reed Dickinson wrote:

Greetings fellow Tekkies:
I am enclosing the formula for the Williamsburg Blue paint that Tek
used on their 4XX series of scopes as well as some others. I am now
on my third gallon of it and it has always proved to be a perfect
match. It has been over ten years since I first posted this formula
and I cannot remember where or how I got it, but it works!

Y = ounces
48 points = 1 ounce

I am not too sure what all these numbers mean, perhaps the people in
the paint store can decipher it. This is what was on the label after
I had my local paint store mix up a batch. It matched perfectly too.
I use enamel as lacquer over enamel can pucker up where enamel on
lacquer is no problem. I carefully clean all dirt, sticker residue
and any other blemishes from the case, lightly sand the entire
surface and spray two light coats on the case with a light sanding
between coats. I paint the plastic parts too using the same
procedure.

B 4Y22 Black
C 33 Yellow Oxide
D 1Y29 Green
W 1Y32 White
E 1Y45 Blue

Base 7-916

Reed Dickinson

On Tuesday, March 24, 2020, 01:22:09 PM PDT, Stephen Hanselman
<kc4sw.io@kc4sw.com> wrote:

If you have the formula, which I take to mean the constituent
colors try a PPG auto paint store.  When I was redoing my TR6 (car
type) they were able to generate an exact match to the factory color
and they make spray cans.  You might also try the local HD or lowes
and see if their color matcher can give you a read out on the base
colors for the match

steve

-----Original Message-----
From: TekScopes@groups.io <TekScopes@groups.io> On Behalf Of JJ
Sent: Tuesday, March 24, 2020 9:27 AM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Tek Blue Paint

Bob, I found this thread from 2009.
https://groups.io/g/TekScopes/topic/7640708?p=Created,,,20,2,0,0.
Reed Dickinson posted a formula. Stan also had the paint made up -
minimum order quantity is 24 spray cans! Stan was selling them for
$15/can. I don't need 24 cans.
The Tek blue subject was brought up back in 2004 and then again in
2009 where the reference to 2004 was made.
It's still not clear whether Reed's posted formula came from Tek or
whether he had a sample analyzed by a paint firm? And, whether
Stan's paint was Reed's same formula made by Sherwin Williams?

John Justin








John Goller, K9UWA & Jean Goller, N9PXF
Antique Radio Restorations
k9uwa@arrl.net
Visit our Web Site at:
http://www.JohnJeanAntiqueRadio.com
4836 Ranch Road
Leo, IN 46765
USA
1-260-637-6426


Re: Tek Blue Paint

Bert Haskins
 

On 3/23/2020 11:11 PM, Brendan via Groups.Io wrote:
The closest I have been able to come is Bahama Sea by Krylon.
I bought some of this for my 22xx scopes and it is way off, at least for matching.

- Bert



Re: TDS3000B calibration

amirb
 

for fast rise pulser, is it possible to use one of Leo Bodnar's? is the frequency really important?


Re: TEKTRONIX 491 measuring wifi signals

 

By the way, this high bandwidth scope I mentioned, the tektronix DPO70000SX, can sample at 200 Giga-samples/sec, with 5 pico-second sample resolution. And the price of this instrument with asynchronous time interleaving, ATI, starts at a mere $315,000.00 I know, it leaves my beloved 547 in the dust! But... I seldom need to measure anything with a 5 pico-second resolution. I enjoy the most with audio signals, ultrasound and signals up to the low RF frequencies. If someone were to give me one as a present, I would sell it promptly and with the money buy a Fazioli concert grand piano.


Re: TEKTRONIX 491 measuring wifi signals

 

Hi Jim,

I was not aware that microwave ovens are replacing the minitron with solid-state power amplifiers that operate at microwave frequencies. This gives a good reason to use the 491 spectrum analyzer. It should be even more fun to observe the microwave signal with a real-time oscilloscope. The Tektronix DPO70000SX 70 GHz oscilloscope seems perfectly made for this. But I have little patience to wait the 50 years that would make this scope more affordable like today is a 500 series scope. So I will pass on this one.

About traditional microwave ovens being either on or off, this is not always the case. I have been using for over a decade the Panasonic "inverter" type of ovens that even at the lowest power setting run continuously, just feeding the magnetron with a lower voltage, I assume. I haven't disassembled one of these yet, but I will do as soon as mine fails. Contrary to what NXP says, they can run for many more hours as they say they do.

Ernesto


Re: Tek Blue Paint

Reed Dickinson
 

Greetings fellow Tekkies:
I am enclosing the formula for the Williamsburg Blue paint that Tek used on their 4XX series of scopes as well as some others. I am now on my third gallon of it and it has always proved to be a perfect match. It has been over ten years since I first posted this formula and I cannot remember where or how I got it, but it works!

Y = ounces
48 points = 1 ounce

I am not too sure what all these numbers mean, perhaps the people in the paint store can decipher it. This is what was on the label after I had my local paint store mix up a batch. It matched perfectly too. I use enamel as lacquer over enamel can pucker up where enamel on lacquer is no problem. I carefully clean all dirt, sticker residue and any other blemishes from the case, lightly sand the entire surface and spray two light coats on the case with a light sanding between coats. I paint the plastic parts too using the same procedure.

B 4Y22 Black
C 33 Yellow Oxide
D 1Y29 Green
W 1Y32 White
E 1Y45 Blue

Base 7-916

Reed Dickinson

On Tuesday, March 24, 2020, 01:22:09 PM PDT, Stephen Hanselman <kc4sw.io@kc4sw.com> wrote:

If you have the formula, which I take to mean the constituent colors try a PPG auto paint store.  When I was redoing my TR6 (car type) they were able to generate an exact match to the factory color and they make spray cans.  You might also try the local HD or lowes and see if their color matcher can give you a read out on the base colors for the match

steve

-----Original Message-----
From: TekScopes@groups.io <TekScopes@groups.io> On Behalf Of JJ
Sent: Tuesday, March 24, 2020 9:27 AM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Tek Blue Paint

Bob, I found this thread from 2009. https://groups.io/g/TekScopes/topic/7640708?p=Created,,,20,2,0,0. Reed Dickinson posted a formula. Stan also had the paint made up - minimum order quantity is 24 spray cans! Stan was selling them for $15/can. I don't need 24 cans.
The Tek blue subject was brought up back in 2004 and then again in 2009 where the reference to 2004 was made.
It's still not clear whether Reed's posted formula came from Tek or whether he had a sample analyzed by a paint firm? And, whether Stan's paint was Reed's same formula made by Sherwin Williams?

John Justin


Re: Tek Blue Paint

John Williams
 

If it helps, here is the information from an old can of Stan’s paint:

Opex L61 Lacquer
L61XXXL42-4383
Tek Blue
05/05/2011
Portland Commercial #4383
To reorder (503) 249-0222

I contacted them a few years ago at that phone number and I was told they could supply it. However the minimum order was 24 cans. So I decided to improvise.

John


Re: Tek Blue Paint

Stephen Hanselman
 

If you have the formula, which I take to mean the constituent colors try a PPG auto paint store. When I was redoing my TR6 (car type) they were able to generate an exact match to the factory color and they make spray cans. You might also try the local HD or lowes and see if their color matcher can give you a read out on the base colors for the match

steve

-----Original Message-----
From: TekScopes@groups.io <TekScopes@groups.io> On Behalf Of JJ
Sent: Tuesday, March 24, 2020 9:27 AM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Tek Blue Paint

Bob, I found this thread from 2009. https://groups.io/g/TekScopes/topic/7640708?p=Created,,,20,2,0,0. Reed Dickinson posted a formula. Stan also had the paint made up - minimum order quantity is 24 spray cans! Stan was selling them for $15/can. I don't need 24 cans.
The Tek blue subject was brought up back in 2004 and then again in 2009 where the reference to 2004 was made.
It's still not clear whether Reed's posted formula came from Tek or whether he had a sample analyzed by a paint firm? And, whether Stan's paint was Reed's same formula made by Sherwin Williams?

John Justin


Re: Craigslist; Lynchburg, VA: 7xxx Scope

John Clark
 

Looks like it's gone. Hopefully, someone here was able to grab it and keep it out of a scrap bin.

John in Charlotte

________________________________
From: TekScopes@groups.io <TekScopes@groups.io> on behalf of David DiGiacomo <daviddigiacomo@gmail.com>
Sent: Tuesday, March 24, 2020 12:37 PM
To: TekScopes <TekScopes@groups.io>
Subject: Re: [TekScopes] Craigslist; Lynchburg, VA: 7xxx Scope

Looks like a 7904 mainframe.

On Mon, Mar 23, 2020 at 8:35 PM John Clark <johnclark05@outlook.com> wrote:

Anyone in the Lynchburg, VA area interested in a 7xxx scope with plug-ins? I'm not familiar enough with them to know exactly which model it is from the single picture but looks to be free for the first one to come pick it up. Listing says it works. I've no affiliation with the owner. It just popped up in a saved search I have.

https://lynchburg.craigslist.org/zip/d/lynchburg-tektronix-oscilloscope/7097981758.html
[https://images.craigslist.org/01717_JnH9hntqVw_600x450.jpg]<https://lynchburg.craigslist.org/zip/d/lynchburg-tektronix-oscilloscope/7097981758.html>
Tektronix Oscilloscope - free stuff<https://lynchburg.craigslist.org/zip/d/lynchburg-tektronix-oscilloscope/7097981758.html>
To the best of our knowledge, this works! Will remove listing once someone picks it up. Please...
lynchburg.craigslist.org

John
Charlotte, NC



Re: TEKTRONIX 491 measuring wifi signals

Miguel Work
 

Mmmmmmmh, some mechanical attenuator, like a band pass gear, like an stroboscope?



-----Mensaje original-----
De: TekScopes@groups.io [mailto:TekScopes@groups.io] En nombre de greenboxmaven via Groups.Io
Enviado el: martes, 24 de marzo de 2020 14:28
Para: TekScopes@groups.io
Asunto: Re: [TekScopes] TEKTRONIX 491 measuring wifi signals

Is there a limit to how fast a magnetron can get the swirling electrons "up to speed" and begin producing an output? Radar sets do use some sharp pulses, do accommodations have to be made for the magnetron's response?

Bruce Gentry, KA2IVY

On 3/24/20 8:44 AM, Chuck Harris wrote:

Heading back to 491's, and wifi signals:

Modern microwave ovens have replaced the heavy, and copper laden,
power transformers with switching power supplies...
which is why they are now available for less than $100.

There is a big cost, however. High voltage capacitors are still
expensive, so the new supplies aren't at all well filtered, and end up
modulating the 2450MHz nominal magnetron output at the switching
supply rate, and the switching supply rate is not at all stabilized,
so it changes with load. This wreaks havoc with wifi routers which
occupy the same ISM band as do the ovens.... Only the ovens leak way
more power than the routers put out.



-Chuck Harris
on off timer that im Ford wrote:
I stand corrected (not all that unusual). Thanks, Chuck. My guess
would be that microwave oven manufacturers either don't know about or
don't want to deal with the subtleties of magnetron anode and
filament voltages and currents.JimSent from my Verizon, Samsung
Galaxy smartphone


Re: Tek Blue Paint

nonIonizing EMF
 

On Tue, Mar 24, 2020 at 07:12 AM, JJ wrote:


From what I remember, a spectrophotometer (with more than 30 filters) is
only 90% accurate at the very best - and that assumes that you can measure
both reflected light from and transmitted light through the specimen - so
one would need a paint chip.
Maybe a generic spectrophotometer like you're noting that is a limited number of filters and not the best correlation/calibration method. A dispersive (diffraction grating) or FT (interferometer) instrument I'm thinking off the top of my head can perform better than 90% accuracy or for an ID method... be valid specific. Even a webcam cardboard box CD as the diffraction grating spectrometer using Theremino is capable of better than 90% accuracy I'm thinking. Please... correct me if I'm wrong.

I used the FTNIR spectrum range that isn't actually related and getting specific valid methods. Granted, I didn't get into the colormetrics in detail. Actually, would be nice to go back and see what all the data looks like now days from the population of data and not only sample sets stats. I last left off with mixtures and potential for impurities qualitative and quantitative detection automatically. I'm not a UV-Vis expert... though I can't believe 90% accuracy with all the range of methods used for calibrating even monitors and colors to only be 90% accurate. Worth reading into so to see what the most accurate cost effective methods are now days.

I know someone has a nice optical Tektronics spectrum analyzer out there.

Wondering what the accuracy of the 7J20 optical spectrometer plugin is?

I have this vision, and have been dreaming about lately, making an equivalent and better than module... maybe for the 5000 series also.


Re: Craigslist; Lynchburg, VA: 7xxx Scope

Eric
 

The time bases look to be a 7B85 and a 7b10 if that is true then a 400 Mhz and 1Ghz time base.


Looking for a readout board for a 7603

Eric
 

I have a 7603 with a readout board that wont show a trace and the readout is really scrambled. It is also showing mainly 9's across the top and bottom of the screen. Just seeing if there is out out there.


Re: Tek Blue Paint

Greg Muir
 

“Spray can consistency” is the big issue. I don’t know how many times I have received a piece of legacy equipment where it was painfully obvious that the person who tried did their best but there was visible feathering borders from the poor spray nozzle pattern and inability to distance the can from the workpiece.

I cleaned up one 7 foot rack in a Tek blue color simply by taking a paint sample to the local hardware store and having them match it in a water-based latex. Application was by a fine-nap roller producing a factory perfect job for $15. The paint wears well and any touch-up from scratching is very easy.

Cleanup ia also much easier given the paint base.

Greg


Re: Craigslist; Lynchburg, VA: 7xxx Scope

David DiGiacomo
 

Looks like a 7904 mainframe.

On Mon, Mar 23, 2020 at 8:35 PM John Clark <johnclark05@outlook.com> wrote:

Anyone in the Lynchburg, VA area interested in a 7xxx scope with plug-ins? I'm not familiar enough with them to know exactly which model it is from the single picture but looks to be free for the first one to come pick it up. Listing says it works. I've no affiliation with the owner. It just popped up in a saved search I have.

https://lynchburg.craigslist.org/zip/d/lynchburg-tektronix-oscilloscope/7097981758.html
[https://images.craigslist.org/01717_JnH9hntqVw_600x450.jpg]<https://lynchburg.craigslist.org/zip/d/lynchburg-tektronix-oscilloscope/7097981758.html>
Tektronix Oscilloscope - free stuff<https://lynchburg.craigslist.org/zip/d/lynchburg-tektronix-oscilloscope/7097981758.html>
To the best of our knowledge, this works! Will remove listing once someone picks it up. Please...
lynchburg.craigslist.org

John
Charlotte, NC



Re: Tek Blue Paint

JJ
 

Bob, I found this thread from 2009. https://groups.io/g/TekScopes/topic/7640708?p=Created,,,20,2,0,0. Reed Dickinson posted a formula. Stan also had the paint made up - minimum order quantity is 24 spray cans! Stan was selling them for $15/can. I don't need 24 cans.
The Tek blue subject was brought up back in 2004 and then again in 2009 where the reference to 2004 was made.
It's still not clear whether Reed's posted formula came from Tek or whether he had a sample analyzed by a paint firm? And, whether Stan's paint was Reed's same formula made by Sherwin Williams?

John Justin

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