[Reber, 1988]
Reber giving a lecture at Ohio State University, 1988 (Photo courtesy of NRAO/AUI/NSF)


[Reber, 1995]
Reber with the reconstructed Jansky antenna, 1995 (Photo courtesy of NRAO/AUI/NSF)


NATIONAL RADIO ASTRONOMY OBSERVATORY ARCHIVES

Papers of Woodruff T. Sullivan III: Tapes Series

Interview with Grote Reber
At the University of Washington
October 25, 1975
Interview Time: 3 hours, 16 minutes
Transcribed for Sullivan by Bonnie Jacobs

Note: The interview listed below was either transcribed as part of Sullivan's research for his book, Cosmic Noise: A History of Early Radio Astronomy (Cambridge University Press, 2009) or was transcribed in the NRAO Archives by Sierra Smith in 2012-2013. The transcription may have been read and edited for clarity by Sullivan, and may have also been read and edited by the interviewee. Any notes added in the reading/editing process by Sullivan, the interviewee, or others who read the transcript have been included in brackets. If the interview was transcribed for Sullivan, the original typescript of the interview is available in the NRAO Archives. Sullivan's notes about each interview are available on the individual interviewee's Web page. During processing, full names of institutions and people were added in brackets and if especially long the interview was split into parts reflecting the sides of the original audio cassette tapes. We are grateful for the 2011 Herbert C. Pollock Award from Dudley Observatory which funded digitization of the original cassette tapes, and for a 2012 grant from American Institute of Physics, Center for the History of Physics, which funded the work of posting these interviews to the Web.

Please bear in mind that: 1) This material is a transcript of the spoken word rather than a literary product; 2) An interview must be read with the awareness that different people's memories about an event will often differ, and that memories can change with time for many reasons including subsequent experiences, interactions with others, and one's feelings about an event.

Part 1 | Part 2 | Part 4 | Part 5

Sullivan

So continuing with Grote Reber on 25 October í75 and he told me that at the Green Bank dish the metal support structures are original, but the surface is new and all of the wooden parts are new. So continuing through your 1958 article about the early days, you say you first tried at 9 cm and your reasoning was that, if it was thermal radiation, a high frequency should have much stronger signal as well as getting a higher resolution. And you say an RCA-type 103A endplate magnetron was acquired for general testing. I wanted to ask you when you say "was acquired," does that mean you were able to borrow one from the company or did you always have to go out and buy all this stuff?

Reber

Circumstances were different in that day, in that we had salesmen that came around and try to sell their products, and these were pretty able, intelligent, and aggressive people who knew their product, they knew their company, and they had good liaison with not only the management but with the factory. Today you get salesmen that don't know their products; they don't know anything, see. They can't even find anything in a catalogue. Well, in any case, in that day there were these salesmen that came around and they were pretty good. And in the local radio industry thereís a fellow could come around in the morning and you wanted a special kind of switch or a capacitor or something, and by God frequently you'd get it in the afternoon. He'd just ring his factory and say now, "Modify so and so and so and so and I'll pick it up." Well, in this A103 magnetron RCA was, of course, sending its reps around. And I'd talk to them not only about what they were trying to sell Stewart Warner, but other things which they might have. And they were pretty able, that is they wouldnít telephone New Jersey, but in a few days when they were back they'd have some literature for me about some experimental thing being made in the Harrison Tube Labs or something. And one of these things turned out to be this magnetron, and so I asked them how much they wanted for one and they already had a price, that experimentally they'd sell them, I think, for $30 a piece or something. So I bought one. But I found out about it through this preferred position in that I had good contacts with the electronics industry.

Sullivan

It really was critical in doing all these experiments.

Reber

That's right.

Sullivan

Going back to the dish momentarily what was the total final cost of the dish? Did you ever add up the figures?

Reber

I don't remember exactly but it was on the order of a $1,000, not very much.

Sullivan

Which is incredibly cheap, even at that time because all of your own labor was put into it.

Reber

Well, yes. But think a $1,000 would have bought a brand new Ford car.

Sullivan

But what kind of a dish can you build now for an equivalent of a Ford car?

Reber

Nothing.

Sullivan

That's what I mean.

Reber

Yes, that's true. In other words for the price of a Ford car today you couldn't get anything.

Sullivan

Ok, moving on further, you talk about a Barkhausen tube was tried and you say, "The vacuum tube construction work was done by the glass experts of the University of Chicago." I was wondering how you arranged that. Was that through being a graduate student there?

Reber

Yes. They had a fellow whose name I don't remember anymore, but they mainly had built things like flasks and pipes and junk for the chemistry laboratory.

Sullivan

All old physics departments used to have glass blowers.

Reber

Yeah. The typical kind of a glass lab a university would have. And I got all the metal parts and just had them put it together. And incidentally, they built this small diode, too. I don't know whether that's mentioned in there or not.

Sullivan

Now, we come to the summer of '38 when you tried these 3300 MHz observations and as you say all this was rather dampening to the enthusiasm when you didn't get any signals. I can imagine that's true. But nevertheless you continued to go on. Was the idea that you had invested so much in the dish that you certainly weren't going to give up with just the first receiver?

Reber

Well, partly that. But don't forget I had in front of me Jansky's results. So it wasn't just a question of hunting wisps in the dark, that is here was some positive evidence. True, I was doing different things. The mere fact that I got nothing didn't necessarily prove that nothing was there. Here was very good evidence there was something there. Now I was at a very different wavelength, by some 40 times or something, and consequently what came out of this, I think as I mentioned, was simply that the phenomena certainly didn't follow Planckís black-body radiation law. Well, nobody knew! Nobody had any idea about what the law might be, I think, I say it might even be an inverse one. So I made a bad guess. That's all.

Sullivan

And you knew that if you went low enough eventually you must detect it, so it was a question of how high could you detect it at.

Reber

Exactly.

Sullivan

Now this is a general question about all of this. I gather that you've been through your archives recently. Are all of the log books and everything, are all of these things still existing from these early observations?

Reber

Oh, yes. I've looked at a lot of them very recently.

Sullivan

You just mentioned that many of them are in Tasmania, do you have some there now?

Reber

Yes.

Sullivan

They're all in Tasmania, including old equipment.

Reber

Everything. It was in storage a long time in Jersey where I couldn't get a hold of it or use it and when I decided I was going to be down there for a while, I had the Research Corp. send everything down there. They were paying big storage fees on the damn stuff, it wasn't doing anybody any good and nobody could get any access to it. So all right, let's quit pumping money down that drain and bring it down to where I can do something with it. This was a very fortunate thing since they [Sullivan: NRAO] wanted me to give this lecture [Sullivan: NRAO Jansky lecture, 1975] on all this old stuff. And I had the opportunity now to dig it out and look at it and examine it. And, as I say, most all of it is in quite good shape.

Sullivan

Great. The old photographs that you took of the antennas and the various receivers and stuff? Well, I've got to get down to Tasmania somehow and see all this.

Reber

I have a couple Iíve brought with me. A funny thing happened but some of these old photographs taken with this camera that was given to me when I was maybe about 12.

Sullivan

Oh, the one you told me about, yeah.

Reber

And peculiar enough it's an ancient camera that you can't get the film for anymore, but technically it has a very good lens. It has a long f-ratio. And so it took very sharp photographs and all these old negatives were very sharp, even the ones taken indoors. Except for a few that were taken by my good mother. She pressed the button with a great vigor and so the damn things got blurred. And I saved them because I'm a pack-rat. And just in the past couple of months an article came out in Science about de-blurring photographs, so I pulled that article out and I have taken out two that I thought might be worth reconstructing. And I folded them all together in an envelope and when I get to Green Bank I'm going to have the Director there write to this bunch and say would they de-blur a couple of these photographs.

Sullivan

Because they are of historical interest.

Reber

See if I get a positive response on that.

Sullivan

That's beautiful. Ok, moving on here. So you have these photographs. You talk here about you had provision to rotate the drum to measure polarization if necessary, which I figure is sort of an amazing step also. Were you expecting that this radiation might be polarized?

Reber

Not really. But you see, going to school I learned about polarized light and in optics in astronomy by that day there had been some polarization measurements, particularly in relation to the solar corona and so on. And so without having to go to a lot of complexity it seemed that it would be worthwhile to include in this general development some provision for checking polarization.

Sullivan

Did you ever make any such measurements?

Reber

No. You see it's easy, see this is circular, all you do is turn it.

Sullivan

And I suppose you have the very first records where you got a positive detection amongst your archives? I really would like to see that someday. Now you use the interesting term, "These preliminary results were published in 1940. The intensity was guessed at by noting the effective resistance shunts across the first tuned circuit. No calibrated signal generator was available then." Now by saying "guessed at," I think you're trying to imply that it was very crude, do you mean an order of magnitude sort of thing?

Reber

Yeah. Well, what happened is that in order to get anything lined up you've got to have some signal generator. So what I built was an oscillator that was really adjustable. Now this is different from tunable. So I adjusted the oscillator to some frequency which I felt was suitable, using a Lecher wire, and then I tuned the receiver to that oscillator. And that receiver shown there...

Sullivan

In the 1940 article.

Reber

That receiver has multiple single tuned circuits, so you just synchronized them all. So that was easy. And then you came up with an output depending on the amount of fluctuation noise in the first tuned circuit. So then you put a resistor across the first tuned circuit and noted what happened to the output. And from this you could guess what the sensitivity was going to be. That's all. So it was a guess, you know, an order of magnitude.

Sullivan

Right.

Reber

That was all built before there were any results. So I didn't go overboard buying hundreds of dollars worth of test gear or building very fancy test gear.

Sullivan

You didn't consider it that important to pin down the negative result that accurately.

Reber

No. After I got some results, then that changed the whole picture. Now that we got some results, let us find out with more precision just what all this is about. And then I built a real good signal generator that I think I mentioned.

Sullivan

Yes, right.

Reber

I've got pictures of that. None were ever published, I think, but I took some pictures.

Sullivan

Ok, now you mentioned that the next paper published in '44 included a polar diagram of the antenna pattern taken on the strong source in Cassiopeia. And indeed that's, as we talked about, the best way to get your antenna pattern. But did you realize that at the time? Apparently not, because then you wouldn't have been quoting these small beamwidths.

Reber

Probably not, at least not in the beginning.

Sullivan

Because you did realize, of course it wasn't known that Cas was a point source in the beginning.

Reber

No.

Sullivan

So I think that's the trouble.

Reber

The antenna pattern was certainly no bigger than that. No, I think in honesty I didn't realize that Cas was telling me that this was the antenna pattern.

Sullivan

That it could be no bigger than that, like you say?

Reber

It could be no bigger, yes, because those other sources down the line that were shown on that same set of contours were all bigger than Cas.

Sullivan

Right, but it still could have been smaller, as you thought it was from your models?

Reber

I suppose.

Sullivan

So it was consistent with what you thought certainly. If you'd found a source in the sky that was only 1į in size then you would have known that something was astray.

Reber

Yes. So I didn't find anything smaller than what the theoretical pattern should have been.

Sullivan

Right. And as you told me in the letter, apparently you went astray using some models. Maybe you can tell me again exactly how you tried to determine the antenna pattern.

Reber

Well, I don't remember the details of that, but it wasn't done at that frequency, it was done at the microwaves.

Sullivan

With the 9 cm?

Reber

Yes, with the 9 cm thing, see. And I had a crystal detector in, and the crystal detector was a very non-linear device. These things have more importance today than they did then. At that time I didn't worry about these matters. The question was whether I could get anything or not.

Sullivan

Right.

Reber

And weíll worry about all this kind of stuff once I get something to measure. There was nothing to measure.

Sullivan

No, I agree with you totally. But you can see, of course, where it's of interest now to try and see exactly how it developed. And especially, for instance, when you had some bumps that you thought were the Andromeda nebula, but in fact...

Reber

They were just drifts.

Sullivan

They were narrower than any your antenna could possibly have picked up.

Reber

That's right!

Sullivan

As Van de Hulst pointed out. So it would have been useful to you in that respect anyway.

Reber

I think I tried to correct that in here somewhere, didn't I? It's mentioned somewhere that...

Sullivan

In this article?

Reber

Yes, towards the end.

Sullivan

I don't remember. The next point I have here is that when you detected the Sun in '43 that if the radio source were a size of the optical disk, a half a degree, that you'd have a temperature of about a million degrees. And you say this had no meaning at the time. And I think it's also true that you did not point it out at the time when you made your measurement.

Reber

No, no I didn't.

Sullivan

Did you realize this at the time, did you make any such calculations at that time?

Reber

No. I pointed out that it had an intensity similar to what the intensity was in Sagittarius.

Sullivan

Right.

Reber

And as far as converting it back to temperature on the disk, no. I just pointed out at that time that it was far in excess of anything that might be expected. That is, orders of magnitude.

Sullivan

I wanted to ask you: now working at 480 MHz you talk about, "Even before the four-stage amplifier was finished, it was clear that it would be rather ineffective. By using special dispensation, I secured some GE 446B lighthouse tubes in í45." What does that mean?

Reber

Well, see this was just at the end of the War and most all of this stuff was still classified in some manner or another. And there was a very limited production of these lighthouse tubes for certain radar things. They were used, I believe, as local oscillators. And consequently they weren't an open market thing. But again through my connections in the radio industry I was able to get these things, the same as I got those orbital beam multipliers. And I got others, there was a sample I picked out of boxes called a beam deflection mixer, which was never used. But I got an assortment of this stuff through those channels.

Sullivan

When you first picked up the burst from the Sun and this was in '46 I think, summer of '46, is that right? [Sullivan: 21 November 1946]

Reber

I guess so, sounds like it.

Sullivan

And this is what you were describing to me earlier about well, about that time anyway, when you had some visitors down there and the bursts came in the sidelobes.

Reber

That's right, solar activity was rising.

Sullivan

Were you reading Nature at that time? Had you seen Hey's thing and the very early thing Pawsey things?

Reber

No. I didn't learn about Hey until after I got to Washington in 1947 or 1948.

Sullivan

Really, I see. So you were operating completely independent.

Reber

Apparently.

Sullivan

Also of Pawsey's group?

Reber

Yes. I don't seem to remember much about that. I'm pretty sure I didn't learn about Hey until later. If I did it was just before I left Wheaton. When did Hey publish his stuff?

Sullivan

Right after the War ended in early 1946. And Pawsey's first paper was also in early '46, same with Ryle.

Reber

Well, I knew about it but I can't tell you the date. I don't remember just when it was. It may have been a year afterwards.

Sullivan

But it's certainly true that when you first detected the Sun in '43 that you didn't know about Hey or Southworth.

Reber

No.

Sullivan

Because you didn't have access to those reports.

Reber

No, I didn't have access to anything. You see, several people could be called the discoverers of solar radio waves, including the Germans, all independently.

Sullivan

Sure.

Reber

And they all came to light later.

Sullivan

Right.

Reber

And Southworth wrote me that the only reason he was able to get that article of his published in the Journal of the Franklin Institute was because I had already published mine.

Sullivan

I see. That was the final reason the military let him do it?

Reber

Yeah, that is he had written up all this stuff and attempted to get it published. And it had been knocked back by the military. That must have been shortly after he discovered it, whenever it was, late '42. And then my stuff appeared in 1944, and at that point then he went back and made further representations to the military and he said that they finally condescended to allowing him to publish it provided he expurgated all the details on the equipment. He was very annoyed, undoubtedly.

Sullivan

Right, but if you look at his paper, he was very clever, you can read off on the charts and still see exactly what the frequencies are and from the frequency and knowing the drift scans he gives, you can deduce the size of his antenna, which he wasn't supposed to mention either. And you get an idea of his sensitivity also from these charts, so the information is there.

Reber

Yes, you need to know how to read it.

Sullivan

But he got past the censor, anyway. Now you mention here that Van de Hulst visited you, I guess, in the autumn of '45. Can you tell me about that?

Reber

Van de Hulst was in Holland during the period of the German occupation and I gather things were sort of unhappy at that period. I guess the astronomers had to go out and dig in the gardens to raise vegetables to get something to eat, on that general level. Anyhow, according to Van de Hulst I gather it was Oort that was cognizant of this transition in the hyperfine structure...

Sullivan

Well, no. I've gotten that whole story from Van de Hulst. I can tell it to you.

Reber

Well, that's all right.

Sullivan

It was actually he that found it. Oort said, "Try to see if you can find a line," and Van de Hulst went out and actually found the transition and worked up the details.

Reber

I see. Well, in any case, he showed up shortly after the War, in late '45 or early '46.

Sullivan

At Yerkes?

Reber

In Yerkes, yes. He was some kind of visiting scientist and he was making a tour of America apparently. He didn't come immediately to Yerkes, I think he'd been to Harvard, Princeton, a lot of places. And then he came out to Yerkes. And, of course, at that time the fellows at Yerkes were very cognizant of what I was doing. And so he hadn't been there more than a few days and they brought him down to me. I donít remember who all came with him. It was two or three other people. And so at that time I was trying to build a 480 megacycle receiver that would get something and it was already evident that the sensitivity was going to have to be pretty good. And he wanted to know what I thought of the possibility of detecting something at 1420 megacycles and I took a rather dim view of it because it looked to me as though it was beyond the present technological capabilities. And then I tried to question him and it really was more an idea than a theory, that is here was this transition in hydrogen and there was hydrogen out in space and I couldn't get out of him and he didn't know whether this transition was going to show up in emission, whether energy was being fed into it or whether it was going to show up in absorption like Hartmannís lines of calcium. And as to where to find it, finally he gave me the obvious answer, you look towards the center of the Milky Way. Well, ok, it's a theory of a sort, but not the kind of thing that you knock yourself out on. So I didn't do anything about it until quite a bit later. And I think I mentioned later I'd built some signal generators and stuff.

Sullivan

Well, let me first ask you, you say that if the line was going to be in absorption, it would be practically hopeless. If in emission, there might be some possibility. What was the reasoning for that?

Reber

Maybe not any very good reasons but you can always detect something better than you can detect nothing. That's all.

Sullivan

Ok, so you weren't thinking in terms of like we do now, of a profile where you compare off-frequency with on-frequency?

Reber

No.

Sullivan

You were just thinking of a single channel?

Reber

Did I mention how I was going to do this?

Sullivan

I don't think so. You talk about building the signal generator and that the GE lighthouse tubes would not be satisfactory, Sylvania tube. You have a multi-stage amplifier, "Provided the amplifier was good enough to detect the continuum, it seemed likely that a fairly strong absorption line might be detected. If the line were to appear in emission, then so much the better." Oh, I get the idea, that that's just a stronger signal.

Reber

That's all.

Sullivan

I see. It's not a matter of the contrast between on-line and off-line. "The entire set-up was never completed," because you moved away in '47.

Reber

Did I mention anything in there about an echo box?

Sullivan

Yes, you said, "It was intended to insert the echo box in the chain."

Reber

That's the tuned system.

Sullivan

Which would give you a resonance at 1420?

Reber

Yes. The idea was, coming here with your antenna, you go through a broadband amplifier. That thing ultimately got partially built with these rocket tubes, I think. I got, I think, 13 dB per stage and about, I think, 15 megacycles [Sullivan: bandwidth]. Anyhow, then this was to go into a diode detector, just conventional, then down through dc amplifier meters. That was for running the continuum. Now, if you could find the continuum, presuming all this worked, then you put a highly selective tuned circuit right in here. And this tuned circuit was adjustable.

Sullivan

So you had a filter?

Reber

That's right. And this echo box is nothing but a filter, an adjustable tuned filter. And then you would tune this filter along until you found a bump in the output. That was the idea.

Sullivan

I see.

Reber

And I took some pictures of that echo box just recently. It's pretty big, it's about this big in diameter and about that tall. It's one I got on the surplus market somehow, I don't remember the details now. But it was used in some military capacity which I donít remember, or donít know even. Anyhow, it had a Q of about 70,000. Now if you take...

Sullivan

That's a 50th of a MHz.

Reber

And divide that by 70,000, that's about 20 kHz. So we'd get pretty good resolution.

Sullivan

That's right. It would be just about right, very optimum.

Reber

I don't know. As it turned out, it would have been about optimum.

Sullivan

Lines are 100 kHz wide. But you had no switching technique there?

Reber

No. There wasn't going to be any switching technique.

Sullivan

So it would have had to be very stable to detect the one percent line, or something like that?

Reber

Yes. It probably would have had to be pretty stable.

Sullivan

Did you work at all in conjunction with the Dutch on this or was this also independently after Van de Hulst went away?

Reber

This was all built after Van de Hulst left.

Sullivan

So you just thought it might be a good idea to do and you might well have continued with it if you hadn't moved away?

Reber

That's right. There were a lot of conflicting things, that is the place I was living at was deteriorating. My parents had died and my brother wanted his money out and so did I. In other words we'd like to liquidate this place. And furthermore, the city was growing and they had installed an automobile parking lot next door and there were more and more cars in motion all the time. And the general environment was getting poorer and poorer to do anything like this. So there were these various pressures, you might say, to close up and get out. And the only place that was offering at the time was the Bureau of Standards. If these pressures hadn't been present, in the next year or so I would have finished this [Sullivan: 21 cm project] up. And one of the, well, promises I got when going to NBS was that I would have the facilities to do these things. It didn't materialize. So nothing more was done. It probably would have worked, I donít know.

Sullivan

It had a good chance anyway.

Reber

But you can see this was not the way to do it, really. But I was in a rut, that is I'd built these other things in this fashion, with the wide band amplifiers. The way to do this is the way it's done now, with a superheterodyne and put the selectivity in the IF system.

Sullivan

Hindsight is always very easy.

Reber

People ask me about this microwave stuff in 1937-1938, what IF frequency I used. I didn't have any IF frequency. And they look at me, sort of blank like and I say, "Well, it was just a total-power detector output amplifier system." And the reason, of course, is there was no local oscillator. This klystron thing hadn't yet been invented.

Sullivan

That was during the War.

Reber

There wasn't any. There was no possibility of building a superheterodyne, see. There were only two tubes, one is this magnetron and one is this Barkhausen tube, and neither of those were continuous wave oscillators in the sense that we have continual wave oscillators. They are more like spark oscillators, i.e., they produced oscillations but they weren't a continuous wave, they were a broad spectrum of waves.

Sullivan

A continuous stream of sparks?

Reber

An old spark transmitter produced a bunch of transients which were independent oscillations around some center frequency governed by the tuned circuit. So, you got a flock of side bands. Well, that's all these magnetrons and Barkhausen tubes did, the same kind of thing.

Sullivan

And so a continuous stream of sparks, to make a continuous signal, more or less?

Reber

Yes. The Barkhausen tube, as originated by old Barkhausen, was a triode, where this was the filament and this was the grid and this was the plate. And this was made minus, and this was made plus. And you put a tuned circuit in here, between the grid and the plate with suitable blocking condensers and this grid, of course, had interstices in it and so an electron was attracted by the positive charge, but it went through a hole in the grid and came up here and then was repelled by the negative charge in the plate and fell back onto the grid. And if everything was adjusted properly, this time was equal to one cycle of this time [Sullivan: frequency]. But these things weren't all doing the same. Some of them, you know, maybe were coming up real close and some of them were coming up not so far because they have different thermal velocities. And furthermore, this thing wasn't symmetrical. Mechanically it was irregular. So it didn't produce continuous waves, only sort of like continuous waves.

Sullivan

Yes, I see what you are saying. Speaking of tubes and such, it just came to mind, the work of Potapenko. You may be interested that he's still alive. I talked to him in Pasadena last summer. He told me about the experiments that he had done with this fellow named Folland. But did you know about these in the Ď30s or did you only learn about them later on?

Reber

I think I learned about them later on. I remember now, I didnít know about them at that time. The way they came to light was that after Keenan had been down there to Wheaton a couple of times and Greenstein had been along- see, Greenstein came from out there somewhere. Oh, did he? He was out there anyhow.

Sullivan

Well, eventually he ended up at Caltech, I can't remember exactly when. [Sullivan: ~1948]

Reber

Anyhow, I'm pretty sure I learned about them through Greenstein. Because Greenstein showed me some pictures that Folland or Potapenko had given him of an old Chevy or Ford or something.

Sullivan

Right, I've got copies of those. You might like to see them this evening, I have them with me.

Reber

Well, I saw those pictures from Greenstein and that's how learned about them.

Sullivan

I see. But you didn't know about them in the 30s?

Reber

No.

Sullivan

Well, I have a couple of other questions on your papers, the early papers especially. But are there any other points that I've missed that you'd like to comment on these early days? As to influences on your work or what was motivating you to... I think I've covered most of the major things.

Reber

At the University of Chicago a lot of professors down there that looked upon the students as a necessary nuisance.

Sullivan

That still happens.

Reber

But Arthur Holly Compton had a rather more benign look upon students.

Sullivan

He was the head of the Physics Department?

Reber

No, Henry Gordon Gale was head of the Physics Department. Compton was some kind of an honorary professor. They gave him an extra stipend.

Sullivan

Right, he was above it all.

Reber

Anyhow, he seemed to enjoy the company of young people in the fashion that most of the old fogies down there didn't. And so he didn't talk to just me, but he seemed to be interested in talking to all the young people. And he wasn't bigoted in the sense that some of those guys were down there, that is some of those fellows like Dempster couldn't think about anything except their damn mass spectroscopy. But Compton was interested in and liked to hear about the things that the young people were thinking about. And that didn't mean that they had to think if about what he and his group mainly were doing because what they were doing was high energy physics with the Cockroft thing. And Compton himself was doing some cosmic ray stuff and I wasn't interested in either one of them. But I remember we used to talk about things in general, and he had a rather open mind, compared to say Kuiper, in that Compton said, "Well, you know, we've got very limited senses, and that our comprehension of what is coming down from the sky is really quite limited." You remember in that day all we had was a few cosmic ray particles, which nobody knew where they were coming from, and light. And if our technology improves, we'd probably find that the Earth is being bombarded by a lot of different kinds of rays and particles which we have no comprehension of today. I thought this was rather an open outlook on life compared to some of the dogmatic things that you got out of the others. And I can remember discussing with him about science and scientists and what made a scientist go, that is why was a scientist a scientist? Why did he do these things he did? And I hazarded a guess that the reason the scientists were scientists was probably because science was todayís outlet for adventure. And that in the sixteenth century if you wanted adventure you joined Magellan or Columbus or Balboa or somebody. But those opportunities were long since closed. And that science presented an opportunity for adventure. And he countered with the proposition that he thought well, that was maybe part of it. Some people, he said, thought scientists liked science because it represented knowledge. But that wasn't true. That if all you were interested in was knowledge all you had to do was go down to the library, there was unending amounts of it down there. He sort of agreed that it was the adventure of the discovery of knowledge. In other words, this was the thing which pushed the science along.

Sullivan

It was the process.

Reber

It wasn't the knowledge in itself, it was the making of it. That was his opinion. And I thought this probably was about as deep an insight into the whole affair as any I had seen. I haven't forgotten him. I thought he was a very worthwhile influence at the university. It was unfortunate that he and some others down there got into loggerheads with the president down there at that time, they had several of them. But anyhow, they imported this young fellow Hutchins out of Princeton, and he looked down on scientists. They were a modern-day kind of alchemists that were degrading society. And that he thought that the intellectual kind of stuff which should be dispensed at a great university should be connected with the great thoughts of the great men of the past. And so he was going to teach courses in the classics, which he did, I guess fairly effectively. But he was just as anti and bigoted on his own classics as Dempster was on his mass spectrographs. And consequently he didn't know what was going on in the science laboratories, and cared less. And I'm pretty damned sure that Hutchins didn't know what was going on under the stadium when they were doing those things then [Sullivan: the Fermi fission experiments]. And not because he couldn't find out, but he didn't care.

Sullivan

Right, he had no interest.

Reber

And so there was a schism between the high management that was represented by Hutchins and the management of the more mundane physics and chemistry and the biology departments. Too bad but that's the way it was.

Sullivan

Amazing. That's all very interesting and of course, Compton was very right.

Reber

I thought that he was one of the better ones they had down there really.

Sullivan

Well, moving to some specific questions. In your Proceedings of the IRE article in 1940, you quote an upper limit for the Sun, you try to detect the Sun and you say you don't find it. And yet this level is about 1/4 of the level which you actually finally detected in 1943. Now, do you attribute that to the fact the measurements were so rough in terms of absolute intensities?

Reber

Probably, yes. If you've decided that's a quarter, I'll accept it.

Sullivan

Well, it comes out - it doesn't surprise you at all?

Reber

No, it doesnít surprise me. Itís within a reasonable range.

Sullivan

Right. And I suppose that the upper limits that you give for other astronomical objects that you looked at like Mars and Venus and so forth, that those should also be corrected for the antenna size, beam size and that sort of thing? You were assuming the same parameters? Ok, here, I don't quite understand what you mean in this sentence when you say you've tried to get Vega, Antares, Mars, to no avail, "While some fine structure of radiation patterns seems to be present, the existing equipment is not adequate for its accurate resolution." What did you mean there?

Reber

At this stage I think I was still doing it by hand, wasn't I?

Sullivan

Yes, plotting it every minute.

Reber

Yes. Ok, if you look at all these little wiggles, see, that's what I called the fine structure.

Sullivan

Ok, and you're talking about really a fine structure in what we'd now call a drift scan?

Reber

That's right.

Sullivan

I see.

Reber

Todayís reading of it would say that it was a structure which was commensurate with the resolution of the antenna. That would be today's reading of it. The reading of it as of that time would be the wiggles shown in the curve. And these wiggles didn't repeat and so you couldn't say that these wiggles had any meaning.

Sullivan

Right. But then you also say though that the, "Equipment is not adequate for its resolution." Now you were thinking perhaps that if you had a larger antenna that the signal would become stronger?

Reber

I don't know, could have been.

Sullivan

Or do you mean that the sensitivity wasn't enough?

Reber

"While some fine structure of radiation pattern seems to be present, the existing equipment is not adequate for its accurate resolution. No conclusive measurements have been made on any of the extragalactic nebulae."

Sullivan

Well, maybe resolution here doesn't mean angular resolution. It means the resolution of the problem as to whether it's real or not.

Reber

That probably, let's see, "The equipment was not adequate for its..."Ē

Sullivan

"For the fine structure's accurate resolution."

Reber

Well, repeatability, I think, would be a better word.

Sullivan

I see. Not adequate to make it repeatable. In other words, itís sort of down in the noise?

Reber

Yes.

Sullivan

I see what you are saying. Now in Fig. 2 [Sullivan: in ApJ 1940], I was wondering why these curves are so smooth. Were they made up of one minute dots also?

Reber

Yes.

Sullivan

And you just didn't show the dots?

Reber

As you can see, they're pretty darn straight.

Sullivan

So you just drew the smooth curve. Ok. Here's a small question, here you quote a 162 MHz frequency and in all the other papers you say 160 MHz. Do you remember how that came about?

Reber

No, I don't.

Sullivan

It doesn't seem to jibe with your Wheaton article either, but it's not an important question so don't worry about it.

Reber

I may have run some of these at 162 and I may have run some of them at 160. I can't tell you at this late date.

Sullivan

That could be also, yes.

Reber

Well while I'm thinking about it we were talking about been made on any of the extragalactic this hydrogen line and Van de Hulst and I found out later that this thing had been independently explored in the laboratory at Columbia by Rabi. You know about that?

Sullivan

He measured it accurately in '48 or '49, right. That was what Ewen and Purcell were working on. They had a very accurate frequency.

Reber

Yeah, yeah.

Sullivan

And Van de Hulst calculated 1411 MHz.

Reber

Something like that, yes.

Sullivan

Now in the 1942 in Proceedings of the IRE paper, all of these photographs, are they still existing?

Reber

Yeah. The equipment still existing too.

Sullivan

So if the photographs are worn, you can take new ones!

Reber

Yes. As a matter of fact I have. The only thing that is not existing is that drum [Sullivan: Figure 5].

Sullivan

Is this you up here [Sullivan: in Figure 2]?

Reber

No, that's one of my helpers.

Sullivan

Yeah, it didn't look like you.

Reber

This [Sullivan: Figure 3] is the rear axle of a Model-T Ford truck. So I used Model-T parts and these universal joints and stuff I think are all parts of Model- T's. And the splines that went into them and all that are parts of Model-T's.

Part 1 | Part 2 | Part 4 | Part 5


Modified on Tuesday, 23-Dec-2014 14:30:20 EST by Ellen Bouton, Archivist (Questions or feedback)