Date   
Re: Tek 604: Sad story, and CRT wanted

Tom Bowers
 

Hello Toby,

I have a new CRT for a 604, still in the original box, never used, it was
purchased as a spare that we never installed. How do I contact you off list
and where are you located.
The CRT is in Colorado and I am not there right now, but could make
arrangements for you.

Tom Bowers

On Wed, Jan 15, 2020 at 10:31 PM <toby@...> wrote:

Hi group,

I bought a 604 XY from ebay late last year.

Have been checking the unit out, and while generally in good condition,
it's suffered some indignities, which appear to have destroyed the CRT.

Evidence of this was one corner of the tube faceplate chipped (without
destroying vacuum), ( https://imgur.com/a/aJQytLP ) the front CRT shroud
broken, and the blow was also enough to shatter the rear plastic
retaining clip, leaving the metal two-piece bracket and long screw loose
in the case.

However, the unit did power up to a ... spot. Actually two spots. The
upper spot is the real, controllable spot, while the brighter lower one
is apparently due to internal CRT damage:
https://imgur.com/a/SNQydLJ

So, I'm in the market for a replacement CRT. Potentially these:

154-0633-00 (p1)
154-0633-05 (p1)

But if 602 CRT's are compatible (??) then also:

154-0562-00 (p31)
154-0562-01 (p7) ****
154-0572-00 (p31)
154-0572-01 (p7) ****
154-0727-00 (p31)

154-0634-01 (p31) -- 603

I also have 602's and 603's so they'd be of interest anyway.

Thanks for any assistance

--Toby




Re: 454 HV regulation off

Albert Otten
 

Hi Jack,

For testing continuity between the CRT grid pin and the grid electrode a rather safe method is to test grid-cathode as a diode. You have to remove the socket to isolate the heater from the transformer winding. Supply 6.3 V to the heater and supply DC between grid and cathode with a suitable series resistor for current limiting (0.1 mA or so is enough). No other pins used. Continuity will show up quickly. IIRC 25 V is enough.
This way you don't have to do measurements in the presence of HV.
I hope for you that you can exclude a CRT problem!

Albert

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

Lawrance A. Schneider
 

Hello Mr. Tillman,

I have tried: Dennis Tillman W7PF
@Dennis–Tillman_W7PF
<@Dennis–Tillman_W7PF>
no caps
I can't remember there permutations I've tried a the moment, but each has failed to pass muster : Please enter a valid email address, name or mobile number (i.e. name@..., a name or 10 digit number only).

I would be more than happy to contribute!! What have I done wrong.
-----------
Further, I got this original missive this morning 16 Jan 20 .Why the delay??
I choose to get the group as conglomerate rather than individual missives.

Thank you Mr. Tillman for your efforts.

If you still need more money, I'll try snail mail.

Very gratefully, larry

Re: 2445 EPROMs

Chuck Harris
 

The processor in the 2445 is a 2MHz 6802 microprocessor.
It needs 250ns or faster memory.

Any 27128 you find is fast enough.

Why do you think you need to replace them?

-Chuck Harris

christopherbath@... wrote:

I need to replace the EPROMs in a 2445 oscilloscope. These appear to be two 27128 EPROMs with part numbers 160-1994-09 & 160-1995-09. Does anyone know the access time required for these? I am able to purchase 200ns access time 27128 but wanted to be sure these are sufficient. The existing EPROM part number is covered and I wanted to keep this intact in case I need to reuse these.

Thanks,

Chris



Re: Tektronix 532 LV rail shorted

randolphbeebe@...
 

Thanks Gentlemen, I will put it back on my bench and follow your suggestions. Also, I downloaded the "Circuit Concepts" Tekwiki publication and will read that as well as the 532 circuit description in the manual as John suggested. I am in the process of putting together an electrical work bench as a hobby and can navigate simpler circuits but the fact is I do not quite understand complex interrelationships of the 532 power supply.

The thing that caused me to suspect the rectifier tube sockets is that now there is no voltage reaching C640 at all. So I will check them as well.

Best,

Randy

Re: What Tektronix means to me

Chuck Harris
 

Having designed battery chargers for the US Army, I would
sure love to see your experimental data on rejuvinating lead
acid batteries.

I worked on that nut for a while, and determined that it was
impractical, as the lead sulfate conversion that occurs in
the lead plates during deep discharge did more than simply coat
and insulate the plates.

Lead sulfate is physically larger than the original mossy lead
in the battery plates, and when allowed to grow to excess, will
break up the mossy lead, and leave it to slough off the plates.
This sloughed off lead and lead sulfate usually ends up in the
bottom of the cell, or pierces the highly porous separators,
where it shorts the cell, ruining the battery.

Even if you could remove all of the accumulated lead sulfate,
the remaining mossy lead in the plates would have seriously
reduced surface area, and the cell's capacity would be a small
fraction of the original capacity.

So, if you have cracked that nut, I would sure like to see the
data.

-Chuck Harris

Ancel wrote:

For me...I became an Eng. in the late 80s when I discovered Tektronix 4 channel scopes (advert in Radio Electronics) which were equivalent of about 2 year's salary as a fresh graduate in the Caribbean.
They remained out of reach until many years later in 2012 when I acquired a 2465 and then a 2465/A as part of a Battery regeneration product development lab @ home.
They allowed me to develop and commercialize my first patent-able product.
http://www.mic.co.tt/page/green-tech-facility

I got the electronics bug. after seeing Star Wars in 1977 (as a 12 year old) and then buying a Radio Electronics mag. in a grocery check out aisle that offered an R2-D2 lookalike functional Robot project build.
This year I am launching the World's first electronic steel drum sticks (My countries national Instrument) https://en.wikipedia.org/wiki/Steelpan

Hope to have it on Amazon later this year. Was hoping to do manufacture in P. Rico...but things are a mess there right now.



Re: Thanks Tektronix

Jamie Ostrowski
 

I really enjoy hearing all of these stories. There's so much accumulated
knowledge and talent here it's just unbelievable!

Thanks for sharing the memories...

On Thu, Jan 16, 2020 at 9:29 AM Jim Ford <james.ford@...> wrote:

Rocket sled telemetry, eh? You didn't happen to work with a Mr. Murphy,
did you, Marvin? I understand that Murphy's law arose from a non-keyed
connector in the telemetry harness on a rocket sled. Or is that just a
myth?Jim Ford Sent from my Verizon, Samsung Galaxy smartphone
-------- Original message --------From: Marvin Moss <mmoss@...>
Date: 1/16/20 6:51 AM (GMT-08:00) To: TekScopes@groups.io Subject:
[TekScopes] Thanks Tektronix My thanks to Dennis for the fine job he is
doing. I started my Tek career as a student co-op at Radiation, Inc. in
Melbourne Florida in 1955. I worked in the test equipment dept for the
summer repairing the Tek stuff. I was always amazed at how you could clean
the Tek scopes by washing them with a hose outside in the parking lot and
then letting them dry with no damage to anything inside the scope. Also
Tek even provided silver solder inside the scope in case you did not have
any. I also became a Technician in 1956 (summer) and learned from the
master ( Bill Eddins) how to really use a Tek Scope. We were building a
new telemetry system for Col John Stapp's rocket sled out at Holloman AFB.
I learned a lot about design and testing that summer. I went on to the
University of Florida where I got a PhD in Electrical Engr in 1966 and a 32
year career at Lockheed. Tek has always been a part of my ham radio life
also and I now have 5 Tek scopes presently. Long live Tek!!


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

mosaicmerc
 

Hi Dennis: Can u confirm u got my contribution...protofabtt@...?

Re: Thanks Tektronix

Jim Ford
 

Rocket sled telemetry, eh?  You didn't happen to work with a Mr. Murphy, did you, Marvin?  I understand that Murphy's law arose from a non-keyed connector in the telemetry harness on a rocket sled.  Or is that just a myth?Jim Ford Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------From: Marvin Moss <mmoss@...> Date: 1/16/20 6:51 AM (GMT-08:00) To: TekScopes@groups.io Subject: [TekScopes] Thanks Tektronix My thanks to Dennis for the fine job he is doing.  I started my Tek career as a student co-op at Radiation, Inc. in Melbourne Florida in 1955.  I worked in the test equipment dept for the summer repairing the Tek stuff. I was always amazed at how you could clean the Tek scopes by washing them with a hose outside in the parking lot and then letting them dry with no damage to anything inside the scope.  Also Tek even provided silver solder inside the scope in case you did not have any. I also became a Technician in 1956 (summer) and learned from the master ( Bill Eddins) how to really use a Tek Scope.  We were building a new telemetry system for Col John Stapp's rocket sled out at Holloman AFB.  I learned a lot about design and testing that summer.  I went on to the University of Florida where I got a PhD in Electrical Engr in 1966 and a 32 year career at Lockheed.  Tek has always been a part of my ham radio life also and I now have 5 Tek scopes presently.  Long live Tek!!

Thanks Tektronix

Marvin Moss
 

My thanks to Dennis for the fine job he is doing. I started my Tek career as a student co-op at Radiation, Inc. in Melbourne Florida in 1955. I worked in the test equipment dept for the summer repairing the Tek stuff. I was always amazed at how you could clean the Tek scopes by washing them with a hose outside in the parking lot and then letting them dry with no damage to anything inside the scope. Also Tek even provided silver solder inside the scope in case you did not have any. I also became a Technician in 1956 (summer) and learned from the master ( Bill Eddins) how to really use a Tek Scope. We were building a new telemetry system for Col John Stapp's rocket sled out at Holloman AFB. I learned a lot about design and testing that summer. I went on to the University of Florida where I got a PhD in Electrical Engr in 1966 and a 32 year career at Lockheed. Tek has always been a part of my ham radio life also and I now have 5 Tek scopes presently. Long live Tek!!

Re: What Tektronix means to me

Jim Ford
 

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_Tillman_W7pF> 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@...: 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

Re: 2445 EPROMs

Mark Litwack
 

Hi Chris,

The 2445 and 2465 have Intel D27128 (no suffix) EEPROMs. This is a 250ns part.

Gentle warming with a heat gun can help peeling up all or part of a label without damaging it.

-mark

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

David Berlind
 

What Richard Pope said! Couldn't agree more.

On Thu, Jan 16, 2020 at 1:40 AM Richard R. Pope <mechanic_2@...>
wrote:

Dennis,
What I care about is that you will be able to continue with
Tekscopes@groups.io!!
GOD Bless and Thanks,
rich!

On 1/16/2020 12:37 AM, Dennis Tillman W7PF wrote:
Hi Raymond,

My estimate of when the contributions would finally stop was completely
wrong. I received the final PayPal contributions 3 days ago and I received
the last check by mail yesterday.

Every contribution has been accounted for. Now I need to discuss with
Michael Dunn the best way to proceed now that I know the totals and if
Groups.io will allow us to pay for several years in advance. I will do that
tomorrow, Thursday and I will report what we decide and all of the
contributions as soon as we reach a decision.

To preserve people's identity, names will be removed. Your contribution
amount will be listed by your PayPal transaction. If you sent in a check
you can look for your checking account number to verify the amount we
received.

Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of
Raymond Domp Frank
Sent: Wednesday, January 15, 2020 6:04 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] MEMBERS PLEASE READ: Our annual Group.io
payment is due in 2 weeks.

On Fri, Jan 3, 2020 at 12:06 AM, Dennis Tillman W7PF wrote:

As soon as the donations drop to a trickle which I expect by the
beginning of next week I will post a notice that anyone who still
wants to contribute has
24 hours left. Then it will take me a day to make a spreadsheet of who
contributed and what the contribution was.
I believe the safest way to do this will be to list just the PayPal
transaction numbers and the amounts personal information is revealed
for privacy reasons.
This way everyone can check that their contribution was received and
entered.
Did I miss something?

Raymond







Re: What Tektronix means to me

 

For me...I became an Eng. in the late 80s when I discovered Tektronix 4 channel scopes (advert in Radio Electronics) which were equivalent of about 2 year's salary as a fresh graduate in the Caribbean.
They remained out of reach until many years later in 2012 when I acquired a 2465 and then a 2465/A as part of a Battery regeneration product development lab @ home.
They allowed me to develop and commercialize my first patent-able product.
http://www.mic.co.tt/page/green-tech-facility

I got the electronics bug. after seeing Star Wars in 1977 (as a 12 year old) and then buying a Radio Electronics mag. in a grocery check out aisle that offered an R2-D2 lookalike functional Robot project build.
This year I am launching the World's first electronic steel drum sticks (My countries national Instrument) https://en.wikipedia.org/wiki/Steelpan

Hope to have it on Amazon later this year. Was hoping to do manufacture in P. Rico...but things are a mess there right now.

Re: Ultimately recyclers have to scrap our treasures - an idea so maybe some can survive

Tom Gardner
 

On 16/01/20 01:24, Harvey White wrote:
I'm not sure that goodwill is the best choice.  You seem to be highly dependent on the people who work there, and whether or not they even know what they have.  For all I know (/begin cynical) they may take the power cord and keep it and throw away the electronics when they only get a spot on the screen and not a TV channel (/end cynical).
In the UK many charity / secondhand shops won't touch anything electrical because they cannot economically assess its safety. Maybe that is also true in other countries.

Re: What Tektronix means to me

Polaraligned
 

Dennis, you have an AMAZING story.

Re: What Tektronix means to me

Jean-Paul
 

Dear Dennis, very fine note, I am touched! I think we are the same vintage, I have been an EE since 1968.

Ancient history: As a kid, In the 1950s I was fascinated by high voltage, electronics, radio, Tesla coils, lots of surplus in Manhattan's "radio Row" at Cortland Street!
I couldn't afford a scope, even a Heathkit, but bought the Heath manual (OL-1? OM-3?) and built the tube scope in a plywood (!) case with a war surplus 3" long persistence CRT (3RP7)?

I recall first seeing lots of 500 scopes at Lawrence Berkeley and Livermore labs in 1967.
In 1968, as an EE, Federal Scientific had the newly released Tek 454, also 500 series.
By 1973 I got the TM500 instruments and more TEK scopes. By mid 1980s, bought the AA501 and SG505 for audio AD DA work.
In the 1980s..1990s lots of great TEK equipment at the Ham fleas and Silicon Valley auctions. Now the Ham fleas are decimated!
Today, I have 7104, 7904, 7603, lots of plugins (some very rare) and a few spectrum analyzers.
Of course my favorite scope is 246X/B, of which I now have 5!

As a retired EE I have great enjoyment to maintain and fix them.
Wonderful to have a fine laboratory, with state of the art equipment circa 1970-1990s!
My current project is a 2465B PSU with no output, startup circuit or preregulator buck problem.
I can only marvel at the fine engineering, packaging, usability and documentation that went into each TEK scope and module!

Legacy: Years ago a good friend went silent key, he had a huge collection of TEK equipment.
Along with 5 of his friends, we worked a day a week for a YEAR to test, organize and sell on ebay, Ham fleas and CL.
I suggest that we TEK aficionados exchange some photos of our labs and collections, and find a way to pass on this great legacy technology to a new generation!
Perhaps start a new thread or group: "Tek legacy" ?

Vive le Tektronix!

Jon in Paris

Re: 454 HV regulation off

Roger Evans
 

Sorry, I missed the previous three posts which had overflowed to a third 'page' on my browser!

Roger

Re: 454 HV regulation off

Roger Evans
 

If all the electrodes in the CRT are connected as designed then the final PDA anode voltage only affects the electric field between the faceplate and the faceplate end of the gun assembly. The 454 schematic shows a grid at ground potential connected to pin 10, and on the gun side of that there are the deflection plates and another isolation shield. The electric field in the cathode - grid space should not be affected by the final anode potential (again assuming that all the CRT connections are intact).

In post #163323 you described a situation where the trace could be seen with the beam finder operated and the final anode of the CRT disconnected. Was the trace normally off-screen or was it on-screen but too faint to see without the beam finder switch operated? Was anything else different between this occasion and the earlier situation where the trace was far too bright? Did the trace return to over-bright simply by reconnecting the final anode?

'Normally' disconnecting the final anode gives a dimmer trace with some loss of focus, if you are seeing a very dramatic change then you might check to see if the CRT cathode and grid voltages change when you disconnect the final anode but make no other changes.

Regards,

Roger

Re: 454 HV regulation off

Albert Otten
 

Hi Jack,

A higher PD-anode voltage makes the trace brighter but does not increase the beam current. The cathode voltage w.r.t. to the (fixed) first anode voltage (pin 12 of the 454 CRT) is the important determinant for cut-off voltage. You can read the principles in the "Cathode-Ray tubes" book of the Circuit Concepts series (pdfs at Tekwiki).

Albert

On Thu, Jan 16, 2020 at 12:07 AM, Jack Ohme wrote:


Hmm. I thought maybe a higher anode voltage would cause more attraction,
thus needing a lower grid voltage to compensate? Maybe it doesn't work that
way. Hmf. Quite confusing, indeed. Maybe it isn't the grid at all,
somewhere in the accelerator perhaps?

On Wed, Jan 15, 2020 at 2:50 PM Albert Otten <aodiversen@...> wrote:

I don't think that the (post-deflection) anode voltage itself has any
influence on cut-off voltage. The cathode voltage has, but not so much that
-130 V gives a visible trace I think. Moreover you measured about -1.8 kV
cathode voltage.

Albert