Topics

From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

Chuck Harris
 

The 513D HV module is a little different from the 511, as
I recall, with the 511 having a bolt on top... and the 513
having a solder on top.

The 513D's oil is about an SAE30 transformer oil, smells heavy
of bakelite, or micarta, but not of PCB. I was told years
ago by someone at tek, that it was just mineral oil.

I would imagine the 511 used the same.

As to why, they didn't want the whole thing to arc over. You
can have electrodes much closer together when you use a material
with a high dielectric strength, like oil, than you can when
you use simply air.

I can't make any promises, but I think I still have the innards
of a bad 513D HV module. If I do, I will take some pictures.

I'm not sure when I will do this, but I will add it to my mental
calendar.

-Chuck Harris

Dave Seiter wrote:

What kind of oil was used? I ask because one of mine (I think the 511a) seemed like it was filled with wax, or at least what leaked out long ago looks/feels like wax. What was the reason for burying the HV in oil? One of these days I'm going to have to open both of them up because neither works.
On Sep 16, 2019, at 3:13 PM, Dave Wise <david_wise@...> wrote:

< The vertical amplifier, and attenuator wasn't calibrated, so to make things work, you adjusted the vertical amplifier variable attenuation to exactly fit the waveform on the graticule lines. Then you switched the vertical input to the calibrator, and adjusted it to match the same graticule lines... reading the peak-peak voltage off of the calibrator's pointer dial.>

Thanks for explaining that so clearly. I suppose that using the graticule as a transfer standard was a good idea back when the amp and CRT deflection were not so linear.
I used to think "calibrated graticule" was just marketing. I didn't realize it was an inversion of methodology.

Still, if they gave me one now, I'd be happy to fix it and play with it, oil can and all.

Dave Wise

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Chuck Harris
Sent: Monday, September 16, 2019 2:38 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

The old 500 series worked quite differently from what
became the standard analog scope interface, the 545.

The vertical amplifier, and attenuator wasn't calibrated,
so to make things work, you adjusted the vertical amplifier
variable attenuation to exactly fit the waveform on the
graticule lines. Then you switched the vertical input
to the calibrator, and adjusted it to match the same
graticule lines... reading the peak-peak voltage off of
the calibrator's pointer dial.

The horizontal time was similarly odd.... but at least it
was calibrated to the graticule.

The main time switch selected the decade you were in: 1000us,
100us, 10us, 1us, 0.1us per cm. The secondary time switch
was a two dial multiplier, that had 0-10 on one dial, and 0-0.9
on the second. Typically, you adjusted the timing so that
you had one cycle on the graticule, and read the time off of
the dials.

-Chuck Harris

OBTW, the HV section was in a sealed can full of oil. Which
was a good thing for the bumble bee capacitors in it, but not
too convenient when a 5642 rectifier burned out. You unscrew
the HV insulators, to keep the pressure down, unsolder the
can lid, and extract the HV section. It is exactly the same
configuration as all of the later 500 series, only the HV
transformer is the much larger 2.75" W5 E core... and ran at
400Hz, as I recall... maybe 1KHz.

Dave Wise wrote:
Closest I got was high school (Benson Polytechnic in Portland OR) in the early 70's, where one electronics classroom had a 514D in a back corner. I always felt sorry for the poor old thing, which was never touched as far as I know. Also covetous; but the teacher wouldn't give it up. It was the best instrument in the room, our assigned tools being RCA service-grade boxes.

Dave Wise








Chuck Harris
 

They were loaded with oil/paper capacitors, known as
bumble bee type capacitors... all leaky, both physically,
and electrically.

They were also loaded with 20uf/20uf - 450V Sprague FP
can type capacitors... one for each tube's screen. All
leaky.

And, they had wafer switches, which were often sprayed to
dripping by some user at some point.

The HV was in an oil filled can, which would leak if the
scope was stored on its side... but shouldn't if it was
stored upright. The ceramic insulators were the seal.

-Chuck Harris

Dave Seiter wrote:

What kind of oil was used? I ask because one of mine (I think the 511a) seemed like it was filled with wax, or at least what leaked out long ago looks/feels like wax. What was the reason for burying the HV in oil? One of these days I'm going to have to open both of them up because neither works.
On Sep 16, 2019, at 3:13 PM, Dave Wise <david_wise@...> wrote:

< The vertical amplifier, and attenuator wasn't calibrated, so to make things work, you adjusted the vertical amplifier variable attenuation to exactly fit the waveform on the graticule lines. Then you switched the vertical input to the calibrator, and adjusted it to match the same graticule lines... reading the peak-peak voltage off of the calibrator's pointer dial.>

Thanks for explaining that so clearly. I suppose that using the graticule as a transfer standard was a good idea back when the amp and CRT deflection were not so linear.
I used to think "calibrated graticule" was just marketing. I didn't realize it was an inversion of methodology.

Still, if they gave me one now, I'd be happy to fix it and play with it, oil can and all.

Dave Wise

Dave Seiter
 

What kind of oil was used? I ask because one of mine (I think the 511a) seemed like it was filled with wax, or at least what leaked out long ago looks/feels like wax. What was the reason for burying the HV in oil? One of these days I'm going to have to open both of them up because neither works.

On Sep 16, 2019, at 3:13 PM, Dave Wise <david_wise@...> wrote:

< The vertical amplifier, and attenuator wasn't calibrated, so to make things work, you adjusted the vertical amplifier variable attenuation to exactly fit the waveform on the graticule lines. Then you switched the vertical input to the calibrator, and adjusted it to match the same graticule lines... reading the peak-peak voltage off of the calibrator's pointer dial.>

Thanks for explaining that so clearly. I suppose that using the graticule as a transfer standard was a good idea back when the amp and CRT deflection were not so linear.
I used to think "calibrated graticule" was just marketing. I didn't realize it was an inversion of methodology.

Still, if they gave me one now, I'd be happy to fix it and play with it, oil can and all.

Dave Wise

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Chuck Harris
Sent: Monday, September 16, 2019 2:38 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

The old 500 series worked quite differently from what
became the standard analog scope interface, the 545.

The vertical amplifier, and attenuator wasn't calibrated,
so to make things work, you adjusted the vertical amplifier
variable attenuation to exactly fit the waveform on the
graticule lines. Then you switched the vertical input
to the calibrator, and adjusted it to match the same
graticule lines... reading the peak-peak voltage off of
the calibrator's pointer dial.

The horizontal time was similarly odd.... but at least it
was calibrated to the graticule.

The main time switch selected the decade you were in: 1000us,
100us, 10us, 1us, 0.1us per cm. The secondary time switch
was a two dial multiplier, that had 0-10 on one dial, and 0-0.9
on the second. Typically, you adjusted the timing so that
you had one cycle on the graticule, and read the time off of
the dials.

-Chuck Harris

OBTW, the HV section was in a sealed can full of oil. Which
was a good thing for the bumble bee capacitors in it, but not
too convenient when a 5642 rectifier burned out. You unscrew
the HV insulators, to keep the pressure down, unsolder the
can lid, and extract the HV section. It is exactly the same
configuration as all of the later 500 series, only the HV
transformer is the much larger 2.75" W5 E core... and ran at
400Hz, as I recall... maybe 1KHz.

Dave Wise wrote:
Closest I got was high school (Benson Polytechnic in Portland OR) in the early 70's, where one electronics classroom had a 514D in a back corner. I always felt sorry for the poor old thing, which was never touched as far as I know. Also covetous; but the teacher wouldn't give it up. It was the best instrument in the room, our assigned tools being RCA service-grade boxes.

Dave Wise





Dave Wise
 

< The vertical amplifier, and attenuator wasn't calibrated, so to make things work, you adjusted the vertical amplifier variable attenuation to exactly fit the waveform on the graticule lines. Then you switched the vertical input to the calibrator, and adjusted it to match the same graticule lines... reading the peak-peak voltage off of the calibrator's pointer dial.>

Thanks for explaining that so clearly. I suppose that using the graticule as a transfer standard was a good idea back when the amp and CRT deflection were not so linear.
I used to think "calibrated graticule" was just marketing. I didn't realize it was an inversion of methodology.

Still, if they gave me one now, I'd be happy to fix it and play with it, oil can and all.

Dave Wise

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Chuck Harris
Sent: Monday, September 16, 2019 2:38 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

The old 500 series worked quite differently from what
became the standard analog scope interface, the 545.

The vertical amplifier, and attenuator wasn't calibrated,
so to make things work, you adjusted the vertical amplifier
variable attenuation to exactly fit the waveform on the
graticule lines. Then you switched the vertical input
to the calibrator, and adjusted it to match the same
graticule lines... reading the peak-peak voltage off of
the calibrator's pointer dial.

The horizontal time was similarly odd.... but at least it
was calibrated to the graticule.

The main time switch selected the decade you were in: 1000us,
100us, 10us, 1us, 0.1us per cm. The secondary time switch
was a two dial multiplier, that had 0-10 on one dial, and 0-0.9
on the second. Typically, you adjusted the timing so that
you had one cycle on the graticule, and read the time off of
the dials.

-Chuck Harris

OBTW, the HV section was in a sealed can full of oil. Which
was a good thing for the bumble bee capacitors in it, but not
too convenient when a 5642 rectifier burned out. You unscrew
the HV insulators, to keep the pressure down, unsolder the
can lid, and extract the HV section. It is exactly the same
configuration as all of the later 500 series, only the HV
transformer is the much larger 2.75" W5 E core... and ran at
400Hz, as I recall... maybe 1KHz.

Dave Wise wrote:
Closest I got was high school (Benson Polytechnic in Portland OR) in the early 70's, where one electronics classroom had a 514D in a back corner. I always felt sorry for the poor old thing, which was never touched as far as I know. Also covetous; but the teacher wouldn't give it up. It was the best instrument in the room, our assigned tools being RCA service-grade boxes.

Dave Wise

Chuck Harris
 

The old 500 series worked quite differently from what
became the standard analog scope interface, the 545.

The vertical amplifier, and attenuator wasn't calibrated,
so to make things work, you adjusted the vertical amplifier
variable attenuation to exactly fit the waveform on the
graticule lines. Then you switched the vertical input
to the calibrator, and adjusted it to match the same
graticule lines... reading the peak-peak voltage off of
the calibrator's pointer dial.

The horizontal time was similarly odd.... but at least it
was calibrated to the graticule.

The main time switch selected the decade you were in: 1000us,
100us, 10us, 1us, 0.1us per cm. The secondary time switch
was a two dial multiplier, that had 0-10 on one dial, and 0-0.9
on the second. Typically, you adjusted the timing so that
you had one cycle on the graticule, and read the time off of
the dials.

-Chuck Harris

OBTW, the HV section was in a sealed can full of oil. Which
was a good thing for the bumble bee capacitors in it, but not
too convenient when a 5642 rectifier burned out. You unscrew
the HV insulators, to keep the pressure down, unsolder the
can lid, and extract the HV section. It is exactly the same
configuration as all of the later 500 series, only the HV
transformer is the much larger 2.75" W5 E core... and ran at
400Hz, as I recall... maybe 1KHz.

Dave Wise wrote:

Closest I got was high school (Benson Polytechnic in Portland OR) in the early 70's, where one electronics classroom had a 514D in a back corner. I always felt sorry for the poor old thing, which was never touched as far as I know. Also covetous; but the teacher wouldn't give it up. It was the best instrument in the room, our assigned tools being RCA service-grade boxes.

Dave Wise

Chuck Harris
 

:-)

Kevin Wood G7BCS wrote:

Exactly the same story with my 546, but with a different ending. It was donated to
the school by the local Marconi factory and sat in the science lab at school
gathering dust for several years while we used the basic junk that the school was
issued.

Eventually I asked why it was never used. Too many knobs! Nobody could understand it.
I made a cheeky offer and it came home in my mother's wheelbarrow!

30+ years later and with the benefit of one of Chuck's transformers it still works
very nicely!

Kevin
G7BCS

On 16/09/2019 21:57, Dave Wise wrote:
Closest I got was high school (Benson Polytechnic in Portland OR) in the early
70's, where one electronics classroom had a 514D in a back corner. I always felt
sorry for the poor old thing, which was never touched as far as I know. Also
covetous; but the teacher wouldn't give it up. It was the best instrument in the
room, our assigned tools being RCA service-grade boxes.

Dave Wise


Kevin Wood G7BCS
 

Exactly the same story with my 546, but with a different ending. It was donated to the school by the local Marconi factory and sat in the science lab at school gathering dust for several years while we used the basic junk that the school was issued.

Eventually I asked why it was never used. Too many knobs! Nobody could understand it. I made a cheeky offer and it came home in my mother's wheelbarrow!

30+ years later and with the benefit of one of Chuck's transformers it still works very nicely!

Kevin
G7BCS

On 16/09/2019 21:57, Dave Wise wrote:
Closest I got was high school (Benson Polytechnic in Portland OR) in the early 70's, where one electronics classroom had a 514D in a back corner. I always felt sorry for the poor old thing, which was never touched as far as I know. Also covetous; but the teacher wouldn't give it up. It was the best instrument in the room, our assigned tools being RCA service-grade boxes.
Dave Wise

Dave Wise
 

Closest I got was high school (Benson Polytechnic in Portland OR) in the early 70's, where one electronics classroom had a 514D in a back corner. I always felt sorry for the poor old thing, which was never touched as far as I know. Also covetous; but the teacher wouldn't give it up. It was the best instrument in the room, our assigned tools being RCA service-grade boxes.

Dave Wise

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Chuck Harris
Sent: Monday, September 16, 2019 1:20 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

Hi Dave,

I got my 513D in 1969 as a Christmas present from my EE
father, who worked for the Navy at the Pentagon at the time.

He had some exposure to the instrument, and picked it out
specifically.

I am abundantly aware that the D stands for delay line, as my
father went out of his way to explain, and demonstrate the
significance of that delay line back in 1969. The brain does
what the brain does.

I have no idea what the military contract was that was mentioned
in the TekWiki, only that the 513D came out well before the 517
did. The 513D was mentioned in a 1949 sales blurb, that can be
seen on the tekwiki. The "D" letter came out as an afterthought,
when tek realized they could sell a cheaper scope if they left
that part off. I doubt many got sold.

My DOD EE dad did tell me that the Navy was rather upset with
tektronix during those years because tektronix steadfastly refused
to make ruggedized versions of their scopes.

Tektronix declined the Navy's request because they felt they had
business enough without attempting to meet the Navy's demands.

Contracting engineers kept breaking Navy rules by hauling their
civy tektronix scopes on board the Navy's submarines and ships.
This long preceded the whole LaVoie thing.

Shortly after my Dad gave the present, he borrowed it to work on
a TV, and proceeded to burn out the vertical attenuator switch
and the vertical preamp. So for me the learning fun began.

-Chuck Harris

Dave Wise wrote:
I'm guilty too!

Do you think the 513 was the military contract (1949-1950) that TekWiki says led to the 517, model not identified in the 517 article?

And note that the non-suffix 513 was distributed; once again, "D" signified Delay Line.

Dave

Those rows of tubes marching off to the horizon are amazing.

Chuck Harris
 

Hi Dave,

I got my 513D in 1969 as a Christmas present from my EE
father, who worked for the Navy at the Pentagon at the time.

He had some exposure to the instrument, and picked it out
specifically.

I am abundantly aware that the D stands for delay line, as my
father went out of his way to explain, and demonstrate the
significance of that delay line back in 1969. The brain does
what the brain does.

I have no idea what the military contract was that was mentioned
in the TekWiki, only that the 513D came out well before the 517
did. The 513D was mentioned in a 1949 sales blurb, that can be
seen on the tekwiki. The "D" letter came out as an afterthought,
when tek realized they could sell a cheaper scope if they left
that part off. I doubt many got sold.

My DOD EE dad did tell me that the Navy was rather upset with
tektronix during those years because tektronix steadfastly refused
to make ruggedized versions of their scopes.

Tektronix declined the Navy's request because they felt they had
business enough without attempting to meet the Navy's demands.

Contracting engineers kept breaking Navy rules by hauling their
civy tektronix scopes on board the Navy's submarines and ships.
This long preceded the whole LaVoie thing.

Shortly after my Dad gave the present, he borrowed it to work on
a TV, and proceeded to burn out the vertical attenuator switch
and the vertical preamp. So for me the learning fun began.

-Chuck Harris

Dave Wise wrote:

I'm guilty too!

Do you think the 513 was the military contract (1949-1950) that TekWiki says led to the 517, model not identified in the 517 article?

And note that the non-suffix 513 was distributed; once again, "D" signified Delay Line.

Dave

Those rows of tubes marching off to the horizon are amazing.

Dave Wise
 

I'm guilty too!

Do you think the 513 was the military contract (1949-1950) that TekWiki says led to the 517, model not identified in the 517 article?

And note that the non-suffix 513 was distributed; once again, "D" signified Delay Line.

Dave

Those rows of tubes marching off to the horizon are amazing.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Chuck Harris
Sent: Monday, September 16, 2019 12:06 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

I plea guilty to my brain spontaneously emitting gas about the "D"
being for Distributed. It was, of course, an indication of the delay
line, that allowed you to see the triggering signal.

The 513D, however, announced back in 1949 had a distributed vertical
amplifier containing a host of 6CB6's. That was at least two years
before the 517 showed up in the catalogs.

-Chuck Harris

Dave Wise wrote:
That D suffix indicates Delay line, not Distributed amplifier. (So you could view the edge that triggered the sweep.) Tek's first distributed-amp scope was Type 517.

Dave Wise

Chuck Harris
 

I plea guilty to my brain spontaneously emitting gas about the "D"
being for Distributed. It was, of course, an indication of the delay
line, that allowed you to see the triggering signal.

The 513D, however, announced back in 1949 had a distributed vertical
amplifier containing a host of 6CB6's. That was at least two years
before the 517 showed up in the catalogs.

-Chuck Harris

Dave Wise wrote:

That D suffix indicates Delay line, not Distributed amplifier. (So you could view the edge that triggered the sweep.) Tek's first distributed-amp scope was Type 517.

Dave Wise

Dave Wise
 

That D suffix indicates Delay line, not Distributed amplifier. (So you could view the edge that triggered the sweep.) Tek's first distributed-amp scope was Type 517.

Dave Wise

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Chuck Harris
Sent: Sunday, September 15, 2019 6:57 AM
To: TekScopes@groups.io
Subject: Re: [TekScopes] From 2014: Tektronix Announces Winner of Europe’s Oldest Working Oscilloscope Contest

The 310 is close, but no cigar.

The 511 was the original Tek scope, the 511AD was a
later refined model, with a distributed vertical amplifier.

My working (?) 513D is probably older than Alan's 511AD.

I give it a ? because although I went over it completely
about 30 years ago, it has the selenium rectifiers, which
tend to turn into insulators.

According to Stan G's book:

511 last catalog 1952
511AD last catalog 1955
513 last catalog 1953
513D last catalog 1953

310 last catalog 1958
310A last catalod 1971

-Chuck Harris

Dave Daniel wrote:
Hmmm.. I have (and had back in 2014) a working 310.

As cool as an MDO would be, and not that I want a 'scope that I can't repair when
(not if) it breaks, but there have to be hundreds of owners of vintage Tektronix
'scopes out there that own working 'scopes that are older than the 511 cited in the
post, Europe or not.

I don't recall hearing of this "contest". It is weird that it did not come to light
while it was in progress. Does anyone have any information about the the contest itself?

DaveD

Mlynch001
 

Tom,

My wife found this very funny! She says that I need to go to the pharmacy and pick up a bottle or three. She says, flat out, "no 400 + scopes for you"!

Alan, Pleased to meet you and to finally learn of your collection and your winning the prize.

--
Michael Lynch
Dardanelle, AR

 

Even more powerful is "Angry Spouse 2.0".

On 9/15/2019 7:14 PM, Dave Voorhis wrote:
On 15 Sep 2019, at 23:56, John Williams <books4you@...> wrote:

Umm, I was wondering if you could share the name of the anti-collection medication?
I bet it’s called “Angry Spouse.” :-)


Dave Voorhis
 

On 15 Sep 2019, at 23:56, John Williams <books4you@...> wrote:

Umm, I was wondering if you could share the name of the anti-collection medication?
I bet it’s called “Angry Spouse.” :-)

John Williams
 

Hi Alan very pleased to meet you. Thank you for your contributions and congratulations on your win. Umm, I was wondering if you could share the name of the anti-collection medication? Thanks. John

Mlynch001
 

Dennis,

Well said!

--
Michael Lynch
Dardanelle, AR

 

Hi Alan,

Let me be the first (of many) on TekScopes to congratulate you on winning the MDO scope. I was also less than impressed by all the ballyhoo when Tek chose to make a big deal of the Mixed Domain concept as something new. I've been mixing domains with 7000 scopes for years. There are other domains the MSO can't do that they chose to ignore because it would have deflated their marketing hype.

I am appalled that the people at the event have never see a CRT scope and that they would be amazed by the things you demonstrated to them. I'm reminded that "Those who cannot remember the past are condemned to repeat it." You did all of us a favor by sticking it to them about the capabilities of the older laboratory scopes.

Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Alan Ainslie
Sent: Sunday, September 15, 2019 2:54 PM

I confirm - alive and well and taking medication for collecting obession.

The Oldest Tek Scope competition seems so long ago - I did not make any fuss at the time but it was quite an event - I have a 511 which did not work and was therefore disqualified (it does now), and was rather surprised that the 511AD won the day.

I do remember at the handover of the sexy new toy that the staff had never seen a CRT scope! I was pleased to show that a 555 with SA and signal PIs would do mixed domain, as would the 7854 with logic analyser
- the staff were amazed. My jibe about no real progress fell on deaf ears.

I also confess to buying the Fiches recently. I have not got them yet, but will see what we have and see if there is still enthusiasm in the UK to do some automated scanning. I have The Eddystone Radio Museum and Archive, and although I did not do the work, there was a panic when factory blueprints were not to be destroyed and were quickly microfiched. Well after the event the fiches were scanned, but these were individual schematics rather than pages of manuals, so maybe the Tek Fiche task is a much bigger job. But I am sure that we can assemble a small group to look at the challenge and share the outcome.

Regards

Alan




--
Dennis Tillman W7PF
TekScopes Moderator

Alan Ainslie
 

I confirm - alive and well and taking medication for collecting obession.

The Oldest Tek Scope competition seems so long ago - I did not make any fuss at the time but it was quite an event - I have a 511 which did not work and was therefore disqualified (it does now), and was rather surprised that the 511AD won the day.

I do remember at the handover of the sexy new toy that the staff had never seen a CRT scope!  I was pleased to show that a 555 with SA and signal PIs would do mixed domain, as would the 7854 with logic analyser - the staff were amazed. My jibe about no real progress fell on deaf ears.

I also confess to buying the Fiches recently.  I have not got them yet, but will see what we have and see if there is still enthusiasm in the UK to do some automated scanning.  I have The Eddystone Radio Museum and Archive, and although I did not do the work, there was a panic when  factory blueprints were not to be destroyed and were quickly microfiched.  Well after the event the fiches were scanned, but these were individual schematics rather than pages of manuals, so maybe the Tek Fiche task is a much bigger job. But I am sure that we can assemble a small group to look at the challenge and share the outcome.

Regards

Alan

Dave Daniel
 

Yes, after perusing my copy of "Oscilloscope Development, 1943-57" by Peter D. Hiscocks, I realize that one cannot beat a 511 as the earliest 'Tektronix 'scope.

When I was much younger, I had a Dumont 'scope that was given to me by an uncle who worked for Fisher Scientific. It did not have calibrated amplifier controls, which, at age 11 or so, confused me. I do not remember the model of that 'scope and I have wondered for years how old it was.

The original 511 was made available in 1948.

DaveD

On 9/15/2019 9:56 AM, Chuck Harris wrote:
The 310 is close, but no cigar.

The 511 was the original Tek scope, the 511AD was a
later refined model, with a distributed vertical amplifier.

My working (?) 513D is probably older than Alan's 511AD.

I give it a ? because although I went over it completely
about 30 years ago, it has the selenium rectifiers, which
tend to turn into insulators.

According to Stan G's book:

511 last catalog 1952
511AD last catalog 1955
513 last catalog 1953
513D last catalog 1953

310 last catalog 1958
310A last catalod 1971

-Chuck Harris

Dave Daniel wrote:
Hmmm.. I have (and had back in 2014) a working 310.

As cool as an MDO would be, and not that I want a 'scope that I can't repair when
(not if) it breaks, but there have to be hundreds of owners of vintage Tektronix
'scopes out there that own working 'scopes that are older than the 511 cited in the
post, Europe or not.

I don't recall hearing of this "contest". It is weird that it did not come to light
while it was in progress. Does anyone have any information about the the contest itself?

DaveD