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HP Forum Archive 17

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HP67 Black Box (NNNs, etc.)
Message #1 Posted by John Garza on 24 Feb 2007, 4:33 a.m.

Any interest in an old black box? Does anybody still tinker with NNNs on the 67/97? I found my old black box and was thinking of putting it up on ebay. But then I realized that most HP users wouldn't even know what it is! Geez, I feel old.

-J

      
Re: HP67 Black Box (NNNs, etc.)
Message #2 Posted by Geir Isene on 24 Feb 2007, 5:51 a.m.,
in response to message #1 by John Garza

Very interested. How do you work it?

            
Re: HP67 Black Box (NNNs, etc.)
Message #3 Posted by John Garza on 24 Feb 2007, 12:16 p.m.,
in response to message #2 by Geir Isene

Basically, there are sections of memory in the HP67 that cannot be accessed unless under certain conditions. You may have also noticed the calculator has limited alpha capability (Crd, Error, etc.). These characters can be assembled by the user to make strings of psuedo-alphanumerics. These are called Non-Normalized Numbers (NNNs for short). Much of the work done researching the HP67 NNNs later evolved into Synthetic Programming on the HP41C. It uses the old trick of moving the program pointer to the data area - so then you can "program" new data.

Anyone familiar with the TI-59 remembers how it can repartition program space vs. data registers. Same principle, the TI-59 just made it easier. I recall writing code on the 59 that would literally reprogram itself by storing data in registers, then repartitioning that data to be program lines and then executing them. But that's a tale for another group.

This device has 5 parts:

1. A plug that fits the power connector of the HP67

2. A black Mode Select button

3. A red Crash Recovery button

4. A coarse tuning knob (upper)

5. A fine tuning knob (lower)

To operate, you insert the plug in the HP67, switch the HP67 ON and in W/PRGM mode, and start hitting the Mode Select (black) button while tweaking the knobs. You're looking for a display of (000 84) or (99x 84). depending on which display you get, you can then proceed to entering keystrokes that you have devised to display the proper pseudo-alpha string (sometimes called a Word/Phrase/Graphic).

The box must be tuned to each HP67 and requires quite a bit of finesse and patience.

Although it's meant for use with the HP67 calculator, the NNNs produced can be written to a magnetic card and then displayed on an HP97. However, certain NNNs may burn out the HP97 print head when printed! So care must be taken.

Most of the original work in NNNs was done by Lou Cargile and others of the PPC club back in the 70's.

-John

                  
Re: HP67 Black Box (NNNs, etc.)
Message #4 Posted by Geir Isene on 24 Feb 2007, 12:44 p.m.,
in response to message #3 by John Garza

Interesting. How much for the box?

                        
Re: HP67 Black Box (NNNs, etc.)
Message #5 Posted by Matthias Wehrli on 24 Feb 2007, 12:58 p.m.,
in response to message #4 by Geir Isene

Same question for me...

Letīs find it out through ebay.

Matthias

                              
Re: HP67 Black Box (NNNs, etc.)
Message #6 Posted by Marcus von Cube, Germany on 8 Mar 2007, 6:51 a.m.,
in response to message #5 by Matthias Wehrli

Matthias, you're a bit crazy, aren't you?

I hope you like the box and put it to some useful work. ;)

      
Re: HP67 Black Box (NNNs, etc.)
Message #7 Posted by John Garza on 25 Feb 2007, 11:59 a.m.,
in response to message #1 by John Garza

Ok, guys, it's up:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=270093654884

-John

            
Re: HP67 Black Box (NNNs, etc.)
Message #8 Posted by Geir Isene on 25 Feb 2007, 1:10 p.m.,
in response to message #7 by John Garza

Only one will get it :)

Are there any schematics on how to make one?

                  
Re: HP67 Black Box (NNNs, etc.)
Message #9 Posted by George on 26 Feb 2007, 11:29 a.m.,
in response to message #8 by Geir Isene

Schematics can be found in 65 Notes, Volume 4 Number 5 (June 1977). Schematics, mechanical plans, a parts list, and operating instructions can be found in PPC Journal, Volume 5 Number 9 (November 1978).

            
Re: HP67 Black Box (NNNs, etc.)
Message #10 Posted by Ren on 26 Feb 2007, 12:58 p.m.,
in response to message #7 by John Garza

Wow! I just checked, and bidding was at $103! Maybe I should start building these things with all the parts I have laying around. (Getting rid of parts and making money would provide a nice anniversary present for my wife).

Ren

dona nobis pacem

                  
Re: HP67 Black Box (NNNs, etc.)
Message #11 Posted by John Garza on 27 Feb 2007, 3:33 a.m.,
in response to message #10 by Ren

Yes, but the one for sale is vintage. I'd expect a recently built one to go for about $50. Sorta reminds me of the fellow making new Altairs and selling them for 80% the cost of a genuine one. And he wondered why they didn't sell...

I was thinking of making some more Black Boxes too if my orginal one sells well. I'm looking no so much at the highest bid, but the number of watchers/bidders - (I broke 20 watchers the first day). That tells me people are interested in it. I wouldn't mind seeing a mini-revival in the HP tinkering that I enjoyed so much! Some helpful hints if you're going to make your own:

1) Use knobs/case with markings - it would help a great deal to know the "settings" 2) Use a case small enough that it fits your palm nicely. 3) Swap out the 10 Ohm fine tuning pot for a 20 Ohm with a 20 Ohm fixed in parallel - it's easier to tune.

If you're REALLY technically inclined and don't mind soldering your main logic board; try a phase 1 interrupt switch (V5N1P16). I have a 67 with one of these. It's a tiny glass reed switch just under the case on the right side. Just pass a magnet over the spot, and voila!

And needless to say, you DON'T keep the magnet in your card wallet.

-John


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