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Playing 1/2 inch NASA data reel through 1/4 inch audio reel to reel recorder

T4600C

T4600C

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Joined
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I got a NASA data reel, and I am looking into getting several more. I am talking with a computer museum about digitizing them.

Today I played part of the tape through an AKAI X201D. I did not expect to get any usable data, maybe a faint signal.

This is the tape:

0261_preview.jpg
0216label_preview.jpg

You can find WAV files and spectrograms here: https://drive.google.com/drive/folders/17vss0VXnpmGchf0DuRh3w2wXxNNphkYA?usp=sharing

Test001.wav through Test003.wav were manually moved along the heads. test004.wav and test006.wav was fed along the heads via the capstan at 3 3/4. test005.wav is played at 7 1/2 inches per second.

Test005.wav has a continuous tone.
test006.wav is the very beginning of the tape, and has weird bursts at the beginning.

I do not know anything about data tapes, and how the data was stored. If you know what these sounds mean, please enlighten me.

Do you think this tape can be read on an IBM 1401?

Discuss!
 
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Having done a number of these for JPL, I'd say that this is a 7-track 800 BPI NRZI tape. Depending on the exact tape drive, it can probably be read on a 729-equipped 1401. Making sense of the data, however, is another story. Early 1960s NASA tapes tended to be 7090/94 ones, with later ones, Univac 1100 series right up through the early 1980s.

Or you can send it to me and I'll extract the data. My contacts at JPL say there are thousands of these things kicking around.

I believe that Al Kossow is also working on a similar setup.
 
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Chuck(G) said:
Having done a number of these for JPL, I'd say that this is a 7-track 800 BPI NRZI tape. Depending on the exact tape drive, it can probably be read on a 729-equipped 1401. Making sense of the data, however, is another story. Early 1960s NASA tapes tended to be 7090/94 ones, with later ones, Univac 1100 series right up through the early 1980s.

Or you can send it to me and I'll extract the data. My contacts at JPL say there are thousands of these things kicking around.

I believe that Al Kossow is also working on a similar setup.
Click to expand...

Thank you very much for your reply.

Can you any sense out of the sound recordings I have made? what are the short bursts on test006 and the tone on test005.

I have been talking with the Computer History Museum about digitizing my tapes, do you think they can do a better job? They will try to use their IBM 1401. They also have a flux machine which could digitize any tape.

I would be incredible thankful if you could extract the data. How to best ship a tape? I have to send mine from the netherlands to your place, which I assume is America. Any further tapes I get I might have shipped directly to you from a seller in America. Whatever you want.

I know a lot of people will be excited to look at the recovered data and try to process it.

Is it possible you can try and get the tape identified by the people at JPL? I did scrub off the upper label to reveal the lower label with some more information.

Kind regards,
Niels
 
Paul Pierce in Portland also has the ability to handle these if they're 7 track tapes.

No, I do not think that I could do anything with your audio. Perhaps an examination with a magnetic developer (such as Kyread) and a low power microscope would verify my suppositions. That would at least tell you how many tracks are involved and define the inter-block spacing, if applicable.

There's a faint possibility that these might also be analog telemetry tapes, but a view with a magnetic developer would verify that. However, what I can see of the partially-covered label seems to indicate a standard digital tape, but the note on the label that says "audio" is puzzling. Were that the case, you should be able to get something using an audio recorder to play these back.

I was under the impression that tapes used for analog telemetry back in the 60s was very different from standard 10.5" 1/2" tape, but you never know.

They're definitely digital tapes if you have blocks of data separated by approximately 3/4" of erased space. That's standard 7 track format.

Finally, a lot of these tapes are simple recertified "scratch tapes"--that is, used tapes returned to the scratch pool and run through a certifier (which erases all data). A tape label that specifies contents and the name of the programmer holds out the best hope, but even so, in the lots I've handled, about 10% were recertified scratch. NASA, like a lot of government operations, re-used tapes heavily, trimming off tape at the beginning when it wore out and applying a new BOT marker. Some of the tapes that I've worked on have several hundred feed sacrificed.

A lot of this stuff is mixed-format data (some text, a lot of binary) data that may be very difficult to suss out without the program that created it. For example, here's one of the tapes that I did: Mostly 7094 floating-point data with a few bits of 7090 BCDIC mixed in.

d00447.jpg

So many unknowns here.
 
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T4600C said:
I have been talking with the Computer History Museum about digitizing my tapes
Click to expand...

That's news to me.
Who are you talking to?

As a rule, we don't read tapes other than those in our collection.

You may be talking to one of our volunteers who doesn't know about our digitization policies.
 
Al Kossow said:
That's news to me.
Who are you talking to?

As a rule, we don't read tapes other than those in our collection.

You may be talking to one of our volunteers who doesn't know about our digitization policies.
Click to expand...

I have been talking with Marc, via his YouTube channel Curios Marc.
 
T4600C said:
I have been talking with Marc, via his YouTube channel Curios Marc.
Click to expand...

Marc is a volunteer.
He has no authority to be making commitments for the museum.

Sorry to be hard-nosed about this, but if something goes wrong and your media is damaged, it was NOT
the "Computer History Museum" that damaged them, but a volunteer doing something on his own, possibly
on our restored 1401 system.
 
Chuck(G) said:
Paul Pierce in Portland also has the ability to handle these if they're 7 track tapes.

No, I do not think that I could do anything with your audio. Perhaps an examination with a magnetic developer (such as Kyread) and a low power microscope would verify my suppositions. That would at least tell you how many tracks are involved and define the inter-block spacing, if applicable.

There's a faint possibility that these might also be analog telemetry tapes, but a view with a magnetic developer would verify that. However, what I can see of the partially-covered label seems to indicate a standard digital tape, but the note on the label that says "audio" is puzzling. Were that the case, you should be able to get something using an audio recorder to play these back.

I was under the impression that tapes used for analog telemetry back in the 60s was very different from standard 10.5" 1/2" tape, but you never know.

They're definitely digital tapes if you have blocks of data separated by approximately 3/4" of erased space. That's standard 7 track format.

Finally, a lot of these tapes are simple recertified "scratch tapes"--that is, used tapes returned to the scratch pool and run through a certifier (which erases all data). A tape label that specifies contents and the name of the programmer holds out the best hope, but even so, in the lots I've handled, about 10% were recertified scratch. NASA, like a lot of government operations, re-used tapes heavily, trimming off tape at the beginning when it wore out and applying a new BOT marker. Some of the tapes that I've worked on have several hundred feed sacrificed.

A lot of this stuff is mixed-format data (some text, a lot of binary) data that may be very difficult to suss out without the program that created it. For example, here's one of the tapes that I did: Mostly 7094 floating-point data with a few bits of 7090 BCDIC mixed in.

View attachment 43682

So many unknowns here.
Click to expand...

Really cool that you worked on NASA tapes before, how did that come to be? and how do the tapes usually end up in the 'wild'?

There are many unknowns, but with small steps I believe we can figure this out.

I looked around for Kyread, and buying from their website the shipping cost alone is 150 dollars. I can buy magnetic viewing film much cheaper, do you think it has enough resolution to view the tracks?

If it does have analog telemetry, is there a special type of audio recorder we need to play them on? or will any 7 track multi track recorder do? I do not know if a 1/2 inch 7 track audio recorder exist, 1/2 inch 8 track tape recorders were more common. Today I spooled the tape through my 1/4 inch 4 track stereo recorder again, this time there were 4 to 5 distinct frequency tones in the spectogram instead of one. Could it be overlapping tracks?

Is it possible rectifying a tape causes this continuous tone?

I may get some NASA tapes soon that have a greater potential to hold data:
29091.jpg
18201.jpg

If you PM me your address I could have them send directly to you.
How can I contact Paul Pierce?

If you want to email me, you can use: apollo16uvc@gmail.com

Regards,
Niels
 
My tapes came directly from NASA JPL in Pasadena. I do not own them--and they were returned after data retrieval, along with the data retrieved from them. In other words, it's JPL's property, not mine and I treat it that way.

Kyread is nothing more than 1 to 3 micron iron particles in a fast-evaporating fluid (it used to be a type of Freon, but since that was banned, methyl perfluoroisobutyl ether is used). It is relatively inert, so it does not affect the coating or base material. You shake the bottle up and drop a drop of the suspension on the tape and allow the solution to evaporate. Since the iron particles are so small, you can visualize very small features in the tape. With a decent chemistry lab, it should not be difficult to mix some of this up in your location, assuming that the carrier liquid is legal in the EU.

When I have a new tape, unless I'm very certain about the content, this is always the first step. Tapes labeled as 9 track often turn out to be 7 track and vice-versa. What are you going to believe, your eyes or some lying label? :)

The other thing is preparation of the medium. Normally, the procedure is to "bake" the tape, then run it through a tape cleaning machine. Additional treatment may be necessary, such as lubrication, to get the tape to read. After all, you have no idea of the storage conditions during the 50 or so years that the tape has been in storage. It's not uncommon for splicing tape (used to attach leaders) to dry out and let go, so you have to be prepared for that. BOT and EOT markers similarly dry out and fall off...

The tapes you pictured above are certainly data tapes and definitely 7-track (9 track tapes don't usually occur with even parity). But you can't get your expectations too high. The Apollo program involved hundreds of subcontractors who generated probably tens of thousands of tapes. The GE tapes you show above may be nothing more than engine test data--and like such things, you need a Rosetta stone to interpret it, since it's unlikely that the data will contain any clues. Before the days of high-speed telecom and big disk drives, tape was king. Outfits like NASA ordered tapes by the truckload.

But, if you're willing to take a shot, I'm willing to have a go at it. I'll PM you my shipping address.
 
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What is life without a little excitement? I'm willing to give it a shot.

PM me your shipping address.
 
For general edification, I received the tape (very dirty and in rough condition), but even though it's dated on the label as 1968, my guess was wrong:

9IToU7E.jpg


9 tracks. Must have been written on a S/360 2400-series drive.
 
I took it with a cheap webcam, Al (640x480). I can take it with a higher-resolution camera, if you'd like or even a shot through a microscope. Pick your poison.
 
High resolution with a camera is good enough, with some annotation. Was it NRZI or PE?
I don't know if I've ever seen a good picture of what an actual 9-track tape block looks like.
 
I haven't gotten that far yet, Al. The tape is absolutely filthy, so I'm not going to put it through any tape drive until it's been baked and cleaned. The reel has enough dirt on it to make me wonder if this thing wasn't used as a plant stand. The first few meters appear to be missing, as there's no leader or BOT marker--it just starts in the middle of data block.
 
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