>> Tektronix and VintageTEK
IAN: Hi.
This is Tony and Ian from Tektronix.
TONY: Hey, how are you doing today?
We’re excited to be here.
We’ve got a new video, and it spans 40 years.
IAN: It does.
The story starts with the part closest to us, the Mixed Domain Oscilloscope (MDO).
TONY: Something that you’ve probably heard us talk about before.
IAN: One of the things we’ve mentioned is that it can show frequency and time domain
data together.
And we found out there’s an oscilloscope that Tektronix made in the 70s, called the
7000 series that can also in a very different way and for a completely different reason,
show frequency and time domain data together.
TONY: And we thought, what a great thing to do a video on.
IAN: Great, so, one question: where are we going to find a 7000 series?
TONY: Exactly.
And, in our own backyard, not even three or four miles from here - we’re at the Beaverton
campus - is the VintageTEK Museum.
IAN: So we thought we would take a trip down there and see if they could do a demo of the
7000 series.
And they’ve asked us about the Mixed Domain Oscilloscope (MDO) before, so we thought we
could do a demo of the Mixed Domain Oscilloscope (MDO) for them.
IAN: Hey guys, how are you?
ED: I'm Ed Sinclair, co-founder.
How do you do, Ian...
Tony.
STAN: I'm Stan Griffiths
ED: This is Stan Griffiths, he’s the co-founder.
IAN: Nice to meet you.
ED: Bruce Baur, one of our engineers / volunteers.
BRUCE: Chief Engineer and Bottle-Washer.
IAN: Excellent.
Current Engineer and Bottle-Washer.
TONY: Right from the first glance, I can’t believe all the stuff they have in here.
It’s amazing.
They’ve got hardware from every decade of Tektronix’ history, right up through the
1980s.
IAN: And the instruments are in gorgeous condition.
They still run great.
And they have a lot of them hooked up, so that you can see the instruments operate.
TONY: So we’re going to walk through and see a lot of these instruments.
But first I think, let’s just jump right into the reason that we’re here, right:
to see the 7000.
ED: We’ve had the capability of running spectrum analysis and time domain all the
way back into 1964.
The larger 04 mainframes all had four plugin holes.
The left two holes were for vertical amplifier plugins.
TONY: It was that easy?
You pull this little tab?
ED: Oh, yes.
That’s very simple.
TONY: Wow.
ED: Just pull the tab and that’s it.
Then on the far right here, we have the horizontal.
These two are horizontal channels.
Here’s the time base.
Here is a spectrum analyzer plugin that utilizes one vertical channel and one horizontal sweep
channel.
This was one of the first swept front end systems.
IAN: When you say swept front end, this is as opposed to the older swept IF approach.
ED: Correct.
All of the spectrum analyzers before the mid-70s that Tektronix provided - from ’64 on to
the early 70s - were of the swept IF variety.
ED: As you can see, these are pretty jam-packed systems.
TONY: Oh, sure.
IAN: Oh, there’s a circuit diagram on there; I love that.
ED: The 7104 didn’t come around until 1985.
The reason we picked this is it has 1 GHz real-time bandwidth.
IAN: But it’s emblematic of that series of modular oscilloscopes, though.
TONY: Do you guys have a collection here of all the modules that do fit in here?
How many different ones were there?
ED: Thirty-plus.
TONY: Oh, thirty different ones?
ED: Oh, yes.
Differential amplifiers, current amplifiers, all kinds of different things.
Later on, they even actually made a logic analyzer plugin that’d make this a logic
analyzer.
IAN: We’re looking at a frequency-hopping signal: a signal frequency-modulated by a
square wave.
So it’s hopping back and forth.
ED: Yeah, you bright this great new generator.
IAN: You can see in the time domain here, as we reach the right edge of the screen,
there’s a little bit of divergence as we see the high frequency or the low frequency.
And in the frequency display, we can see both frequencies present as the carrier is hopping
back and forth between the two.
ED: It’s been 40 years since I’ve made that demonstration, so I hope I remember all
of it.
IAN: Wow, that was amazing.
A lot of history there.
TONY: Yeah, I was really fascinated by Ed’s demo.
He talked about swept front end?
IAN: Yes.
Traditional spectrum analyzers tune their circuitry across a range of frequencies, or
sweeping.
TONY: Okay, kind of like on your radio when you’re turning it to a different channel.
IAN: Exactly, a lot like that, just over and over again.
The catch is that we’re looking at high frequencies, and the instrument runs at a
lower frequency.
TONY: So, we’ve got to do something right in there.
IAN: The other stage of traditional spectrum analysis is downconversion, which is just
taking a high-frequency signal and turning it into a lower one.
TONY: It seems a little bit complicated.
Are there disadvantages to that?
IAN: Well, it’s all about the order that you do it in.
Based on the limitations of the hardware at the time, they had to downconvert and then
sweep.
This is before the 7000 series came along.
That was called a swept IF architecture.
TONY: OK.
IAN: And it did have some disadvantages.
Ed really says it best, so we’re going to let him say it.
TONY: OK, great.
ED: It was very difficult as a field engineer like myself to demonstrate those products.
Today a lot of the people call those more spectrum indicators as opposed to spectrum
analyzers.
Because as you crank the center frequency and you expect it to go to the right as you’re
cranking it, what’ll happen is you’ll see all the spurs running off in the opposite
direction.
And trying to help the customer interpret all that was pretty difficult.
TONY: But the 7000 didn’t have that problem, right?
IAN: Exactly.
The 7000, instead of downconverting and sweeping, was able to sweep and then downconvert.
And that’s what they call a swept front end spectrum analyzer.
TONY: That’s excellent.
But I’m kind of worried now.
The Mixed Domain Oscilloscope (MDO), that’s another way, too?
IAN: Yes, I’m going to introduce yet another concept.
So the Mixed Domain Oscilloscope (MDO) works by digitizing the signal...
TONY: Yes.
IAN: ...Taking that incoming energy and converting it to numbers.
And now, once it’s in computer memory, you can do anything with it.
We’re going to analyze it mathematically, and find out what’s in that signal.
TONY: FFT, right?
IAN: Exactly.
TONY: We did a video on that.
IAN: Fast Fourier Transform.
TONY: Yes, and what are the advantages of that?
IAN: So, because everything’s in computer memory, you can stop what you’re doing and
go back in time.
So if you have, for example, a signal that’s hopping from one frequency to another, you
can go back and look at any individual hop.
TONY: That’s awesome, and that’s what we’re going to show Ed and Stan in our demo?
IAN: Exactly.
IAN: So what we have here, on the top we have a time-domain display, and on the bottom we
have a frequency-domain display.
On the time-domain display, I’ve gone ahead and turned on frequency vs. time.
IAN: We’re seeing the frequency hop between the high frequency and low frequency up here.
It only needs a certain number of samples to produce this FFT, and that’s represented
by this bar here.
Right now, we’re only looking at the spectrum from this portion of the time record, when
it was all on the lower frequency.
But I can turn this knob... and move it back.
Now, we see only the high frequency.
As I start to jog the knob to the right, we see a little bit of the low frequency climbing
up.
As I move it a little more, now they’re roughly equal.
And then the high frequency starts to fade away, until we’re looking just at the low
frequency.
So it’s really just two different takes on the same data but I was just really delighted
to see that spectrum and time were living together on an oscilloscope for a long time
and we would have the chance to come and talk to some of the people who were there.
TONY: That was amazing.
Oscilloscopes and spectrum analyzers together, in the 70s.
IAN: I know, right?
And that’s just the tip of the iceberg of what they have.
They have things like the first model oscilloscope that Tektronix made back in the 40s.
Still runs.
TONY: Man, so if I calculate right, that’s some pretty good quality.
IAN: Nearly 70 years later and it still runs.
We should all hope to build the same quality into our work today.
TONY: Yeah, I really enjoyed that tour, too.
The back area with the manuals.
IAN: And the repair depot.
TONY: Yes, and all the different parts they had.
They had racks of Tektronix instruments, and they’re still coming in.
People are still donating them.
IAN: It’s wild.
So let’s take a look at that now.
TONY: Okay.
ED: Here along this wall, we have a manual collection.
IAN: So if we name the model, you can find the manual for it.
ED: Either we have it here, or we have it in microfiche.
TONY: How handy is that?
STAN: This is our tube supply.
It’s not huge, but it came mostly from my garage.
If you need a 60-J-8, you can look it up in here and find out that the part number is
154-08700.
That’s done by numerical order, so 187 is down here somewhere.
Right here.
IAN: You had that memorized, didn’t you?
STAN: I do.
STAN: This is a B-phase early prototype instrument.
In order to remind himself and help ensure it wouldn’t be sold as a Tektronix instrument,
he painted it yellow.
STAN: I had one of these kits when I was a sales engineer in 1970.
I would carry these in every day to visit my customer.
What I would do is draw parts from it to make a failing instrument function again on the
spot.
BRUCE: This one here is dead because MOS Tech ROMs don’t remember after a while and so
we’re going to have to shoot some programmable ROMs to take its place.
Luckily, we have another instrument of the same variety that works.
The ROMs are still alive.
IAN: It was just so much fun seeing all those old instruments and parts.
It was a real slice of history.
TONY: Oh, man.
It was technical, but we also saw so many other things.
IAN: You’re talking about the people and the camaraderie and the culture, right?
TONY: Oh, the culture.
All the souvenirs and just the stuff that’s beyond the instrument.
It was amazing.
IAN: Every single one of those pieces has a story behind it, and we couldn’t resist
showing you a few.
TONY: Let’s take a look at some of these.
TONY: You’re trying to complete the whole story: not just the instruments, but the whole
culture at Tektronix.
STAN: Yup.
IAN: These are such a big part of that too, these items here.
Do you have a few favorites you could show us?
STAN: Well, this is kind of a neat one right here.
This is a Tektronix slide rule, made by K&E.
IAN: If I wanted to multiply 2 and 3...
STAN: With the left index right over the 2, come up here to the 3, and right below it
is 6.
TONY: That’s before calculators.
IAN: This is a calculator!
STAN: Here’s a deck of cards and a couple of poker chips that are Tektronix.
STAN: This is a book of matches.
TONY: Wow.
What is that, the 422 on there?
STAN: Yes, and here’s one that actually has a couple of matches left in it.
TONY: Oh, man.
STAN: The interesting thing about this is that there’s a typo in the text up here.
It says “high wiring rate.”
What they meant was “high writing rate.”
IAN: Ah, yes.
STAN: So this makes this kind of a classic.
STAN: And this is a blank check with Howard Vollum’s name on it.
TONY: Wow, that’s great.
STAN: Obviously a closed account.
He didn’t sign it either, so we can’t really fill in an amount.
IAN: Right.
STAN: It would be nice if we could, because we could use five times as much floor space.
STAN: Down here at this end is a collection of length-of-service pins.
It’s not a complete collection, but probably the best one we have in here is this one right
here.
I think it’s a 25-year pin.
If you look closely at it, it’s a penknife.
You’ll find two emeralds and a diamond.
STAN: I always refer to this as the corporate aircraft.
Tektronix never actually had a corporate aircraft.
IAN: So, this is Tek Force One, right here.
STAN: Yes, and it’s the only one left as far as I know.
STAN: This is a circuit computer.
The scales are made so that you can do various calculations unique to circuits in oscilloscopes.
STAN: Tektronix indeed does hold the patent on styrofoam peanuts as packing material.
STAN: Here’s a neat little thing that Tektronix used to do for employees.
It’s called a “You Done Good” award.
Any manager could could acquire one of these and celebrate a job well done by one of his
employees.
STAN: There is a wise-guy engineer in every group, and they always have a better way to
do it.
So there is another form on the back side of this, not official Tektronix.
This is the “You Screwed Up” award.
Down here, I really like the wording.
It says right here, “And everybody knows it; we have it on file.”
IAN: Tell me about this.
STAN: We had a guy at Tektronix named Greg Thompson.
STAN: This is a lot like “Dilbert.”
IAN: But in real life.
STAN: Oh, yeah.
Every situation in here, you could identify with; somebody could.
He was a very talented cartoonist, and the only place I know of that his cartoons appeared
was in Tek Week.
Eventually, he made a book of all the cartoons, and here it is.
TONY: Wow.
STAN: This is a collection of, gosh, I don’t know, 50 or 60, maybe more, maybe 100 Tektronix
cups.
TONY: Do you have a favorite, Stan?
STAN: Well, I do!
You see this one here?
This is what I acquired at the 1988 Masters convention.
It’s got all the names of the people that attended, and I’m right there.
I’m on it.
TONY: That’s terrific.
STAN: There I am, Stan Griffiths.
IAN: Guys, thank you so much for having us.
ED: Thanks for coming.
IAN: We've had a blast.
Thank you especially for safeguarding what Tektronix has built and what we hope we’re
continuing to build.
Folks can find out about this place at vintagetek.org.
It’s been a blast.
Thanks so much, Bruce, Ed, Stan.
STAN: Come back again.
IAN: We’ve got one more thing we’d like to show you.
We noticed those “You Done Good” certificates over there.
We actually found one in the office.
And so we would like to present you with a “You Done Good” award for safeguarding
Tektronix’ legacy.
So, thank you very much.
ED: Thank you.
TONY: See you guys.
IAN: Take care.
IAN: What a great day that was.
We got to see a demo of the 7000 series, a distant ancestor of our beloved Mixed Domain
Oscilloscope (MDO).
We got to see all these old Tektronix memorabilia and all these restored instruments.
It was a blast.
TONY: Terrific time!
Anyone can go there, right?
IAN: That’s right.
This museum is open to the public.
If you go to vintagetek.org, that's got their location and hours of operation.
TONY: We hope you guys enjoyed this video.
We enjoyed the day immensely.
Thanks to Ed and Stan again, and we’ll see you in the next video.
IAN: Until then, bye everybody.
TONY: Alright.