The Museum of HP Calculators

HP Forum Archive 21

 HP-71b - what to look for when buyingMessage #1 Posted by Marcel Samek on 14 Feb 2013, 2:01 p.m. I am going to take the plunge and get a 71b to play with. I wouldn't call myself a collector - I just like playing with old calculators. So usability is more important to me than aesthetics or rarity. As I have started looking around on the auction site, I see a very wide range of prices. More importantly, i see people mentioning ROM versions, untampered with rubber feet, and other features which I'm not sure are important or not. Could the 71b experts here let me know if there are any key things to be looking out for. For example, does ROM version matter? Are there any common problem areas to be careful about? What are the "must have" accessories? Thanks in advance.

 Re: HP-71b - what to look for when buyingMessage #2 Posted by Marcus von Cube, Germany on 14 Feb 2013, 2:13 p.m.,in response to message #1 by Marcel Samek Must have: HP-IL and RAM (as much as you can get). Desirable: MATH-ROM (can be overcome with enough RAM and HP-IL, see here!)

 Re: HP-71b - what to look for when buyingMessage #3 Posted by Marcel Samek on 14 Feb 2013, 2:45 p.m.,in response to message #2 by Marcus von Cube, Germany Marcus, how do you typically use the HP-IL?

 Re: HP-71b - what to look for when buyingMessage #4 Posted by Garth Wilson on 14 Feb 2013, 4:13 p.m.,in response to message #3 by Marcel Samek Quote:how do you typically use the HP-IL? It is used for virtually all interfacing to the outside world, including, but not limited to: mass storage (although with enough memory, you can keep everything you commonly use in the computer at the same time and almost never need to access mass storage printers video display lab instrumentation, virtually unlimited through the HP82169A HPIL-to-HPIB (IEEE-488) interface converter RS-232, through the HP82164A or FSI164 converters parallel, through the HP82165A or __ (I can't remember the number of the other one or two that were made) The "L" stands for "loop." The module has an output to the first device on the loop, which also has an input and output port, and its output goes to the second device and so on, until the last device's output comes back to the 71's HPIL module's input. Auto addressing gives a unique address to every device on the loop. Every device knows what class of device it is, what its model number is, what it can do, etc.. Control can be passed from one controller on the loop to another. As you can see, there's a lot of intelligence built in. This interfacing ability, especially for lab instrumentation like signal generators, programmable power supplies, DMMs, relay matrices, RF network analyzers, etc., is why I originally got the 41. The 71's HPIL is about 30 times as fast as the 41's.

 Re: HP-71b - what to look for when buyingMessage #5 Posted by Marcus von Cube, Germany on 14 Feb 2013, 5:04 p.m.,in response to message #3 by Marcel Samek Garth has explained how HP-IL works. It's the 'networking' interface of old. Connect it to a PIL-BOX (by JF Garnier) and you get PC connectivity.

 Re: HP-71b - what to look for when buyingMessage #6 Posted by Marcel Samek on 14 Feb 2013, 5:49 p.m.,in response to message #5 by Marcus von Cube, Germany Thanks Garth and Marcus. I think it is very unlikely I would use most of the HP-IL devices, with the exception of connection to the PC. (Out of curiosity, when you transfer programs to the PC, what format are they in?) Do you know if the Pil-Box is still available to purchase? It looked as if the web site had not been updated in a while so I could not tell.

 Re: HP-71b - what to look for when buyingMessage #7 Posted by Marcus von Cube, Germany on 17 Feb 2013, 6:17 a.m.,in response to message #6 by Marcel Samek The file format is either a disk image file or a LIF file. Look at J-F's emulators for details. I don't know any details about the availability of the PIL-Box. I don't have any other HP-IL devices either but it's the only means of getting data into and out of the 71 except the keyboard and the card reader neither of which can transfer data to or from a PC. With a PIL-Box (or the older HP-IL ISA card) you get a mass storage device of essentially unlimited capacity.

 Re: HP-71b - what to look for when buyingMessage #8 Posted by Jerry Raia on 17 Feb 2013, 12:01 p.m.,in response to message #7 by Marcus von Cube, Germany You can get it here: PIL Box. I got one not too long ago. Works quite well :)

 Re: HP-71b - what to look for when buyingMessage #9 Posted by Andrés C. Rodríguez (Argentina) on 14 Feb 2013, 2:20 p.m.,in response to message #1 by Marcel Samek Just my opinion: ``` a) Avoid any corrosion in battery contacts b) I dont't have it, but Math ROM seems to be close to be "a must" c) HP-IL module may be interesting to obtain d) Memory (RAM) modules are also interesting to obtain e) Card reader may be interesting or not, depending on what you plan to do. f) Aesthetics and completeness of original accessories should be welcome. g) Obtain a complete manual, at least in electronic form. ``` After many years, I took the plunge and (during HHC2011) bought a nice HP 71B from a prominent collector and PPC member, to whom I'm very thankful. It doesn't have the Math ROM, nor extra memory. I don't miss the carrying case or AC adapter a lot, I just use it with AAA batteries. I have had little time to do anything but the most basic things. Overall, I found it less interesting than I expected: Operation seems too slow, CALC mode is of little value for a die-hard RPN user like me, and the single-line display is too limiting. Again, this is just my opinion. Please disregard any idiomatic mistake. Edited: 14 Feb 2013, 2:20 p.m.

 Re: HP-71b - what to look for when buyingMessage #10 Posted by Maximilian Hohmann on 14 Feb 2013, 3:37 p.m.,in response to message #9 by Andrés C. Rodríguez (Argentina) Quote:e) Card reader may be interesting or not, depending on what you plan to do. The problem with the card reader is that the (long) cards are almost impossible to find. I would rather look for an HP-IL tape drive (the drive can be found really cheap, but the tapes are rare and expensive) or even better an HP-IL floppy drive.

 Re: HP-71b - what to look for when buyingMessage #11 Posted by Walter B on 15 Feb 2013, 12:53 a.m.,in response to message #10 by Maximilian Hohmann Quote: ... the drive can be found really cheap, but the tapes are rare and expensive ... Just for curiosity: where? I observe the drives being expensive, and the tape cassettes look like the old dictaphone ones. d:-?

 Re: HP-71b - what to look for when buyingMessage #12 Posted by Maximilian Hohmann on 15 Feb 2013, 4:36 a.m.,in response to message #11 by Walter B Hello! Quote:Just for curiosity: where? I observe the drives being expensive,.. Over the years I bought several of them on eBay and never paid more than 30 Euros for each. I know for sure because 30 Euros is my personal "hard limit" for any calculator accessory. But you are right: The few of them that are listed now are very expensive (over 300\$) - ridiculously expensive even! Quote:... and the tape cassettes look like the old dictaphone ones. They look like them, but are sufficiently different to attract crazy bids on eBay! Regards max

 Re: HP-71b - what to look for when buyingMessage #13 Posted by Egan Ford on 14 Feb 2013, 2:57 p.m.,in response to message #1 by Marcel Samek Quote: I am going to take the plunge and get a 71b to play with. I wouldn't call myself a collector - I just like playing with old calculators. So usability is more important to me than aesthetics or rarity. Play with an emulator first. Then you'll know what you want/need.

 Re: HP-71b - what to look for when buyingMessage #14 Posted by Marcel Samek on 14 Feb 2013, 7:33 p.m.,in response to message #13 by Egan Ford It is good advice and I have played with the emulator, and I am somewhat familiar with Basic based calculators because one of the Sharps took me through university in the 1980s. Unfortunately, if I am honest with myself, I don't "need" the 71b or anything related to it. However, what I "want" is a new toy, in my hands, and in that regard the emulators are very unsatisfying and not very good at predicting the satisfaction one will get from the real product. My question simply had to do my wanting to avoid a bad purchase rather than trying to be too analytic about my needs.

 Re: HP-71b - what to look for when buyingMessage #15 Posted by Garth Wilson on 14 Feb 2013, 10:45 p.m.,in response to message #14 by Marcel Samek Quote:and I am somewhat familiar with Basic based calculators The BASIC in the 71, especially with the Math module and lots of language-extension (LEX) files loaded from the user groups, is far and away better than any other BASIC I've seen. You can type in lines of code with no spaces (in most cases) and it will figure out what you wanted, and catch syntax errors before you try to run it. You can have any number of programs in memory at once, any number of files, and any program or subprogram can call any other one, even itself (recursively), as the subprograms set up their own environments. I wrote a very flexible text editor that I used a lot on mine that let me have over 60 files open at once. After I learned this BASIC and had a lot of free LEX files in RAM, I was introduced to other BASICs and had to work for awhile with even HP BASIC 5.1 (Rocky Mountain BASIC for instrument control) and was extremely disappointed. The 71's was way better. I think HP's Rocky Mountain group could have learned a lot from their Corvalis group. The Math module is quite a performer too. For example, it could do a 1K-point complex FFT twice as fast as the original IBM PC running GW-BASIC could. It handles complex numbers seamlessly. Of course all this is not even the tip of the iceberg. I'm just saying this is not the BASIC you've known. It's a whole new world.

 Re: HP-71b - what to look for when buyingMessage #16 Posted by Marcel Samek on 15 Feb 2013, 12:08 p.m.,in response to message #15 by Garth Wilson I'm a software developer, so I am always involved with lots of code. However it has been many many years since I did anything meaningful with BASIC and I'm looking forward to learning the 71s flavor. I usually try to pick some non-trivial project as a forcing function to help me really learn a new language/platform. With the 15c it was the sudoku solver. Now I just have to actually buy the 71 and pick a project.

 Re: HP-71b - what to look for when buyingMessage #17 Posted by Gerson W. Barbosa on 15 Feb 2013, 2:34 p.m.,in response to message #16 by Marcel Samek Quote: I usually try to pick some non-trivial project as a forcing function to help me really learn a new language/platform. Here is an example of an unusual problem solved with help of the HP-71B BASIC: http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv017.cgi?read=116905 (See message #61, by Egan Ford). Here are some articles by Valentin Albillo that might interest you:

 Re: HP-71b - what to look for when buyingMessage #18 Posted by Marcel Samek on 15 Feb 2013, 2:42 p.m.,in response to message #17 by Gerson W. Barbosa Thank you very much for the collection of links! I had not seen all of them, but it was seeing some of Valentin's articles and his posts in this forum that inspired me to want to play with the 71b.

 Re: HP-71b - what to look for when buyingMessage #19 Posted by Thomas Klemm on 15 Feb 2013, 8:32 p.m.,in response to message #17 by Gerson W. Barbosa Gerson, thanks for reminding me of this Short & Sweet Math Challenge #19 . It made me look at the various solutions and I wondered what I was doing then: Quote: After a little magic What? So I checked with WolframAlpha and noticed that I made a mistake. The correct formula is: $\sum_{k=N}^{\infty}\frac{1}{(2 k+1)^2}=$ $\frac{1}{4N}-\frac{1}{48N^3}+\frac{7}{960N^5}-\frac{31}{5376N^7}+\frac{127}{15360N^9}+O(\frac{1}{N^{10}})$ The coefficient to use with N5 is: ```7 ENTER 960 / STO 5 ``` Fortunately it doesn't have a noticeable effect on the result. Cheers Thomas

 Re: HP-71b - what to look for when buyingMessage #20 Posted by Gerson W. Barbosa on 16 Feb 2013, 4:33 a.m.,in response to message #19 by Thomas Klemm Hello Thomas, Quote: Gerson, thanks for reminding me of this Short & Sweet Math Challenge #19 . It made me look at the various solutions and I wondered what I was doing then: Same here. I've decided to write an RPL version for A- starting from scratch: ```%%HP: T(3)A(D)F(,); DIR FISCHER \<< 10, DUP LN * \Gb NEG 2, 11, FOR n DUP n GET n NEG ALOG * n Zeta * ROT + SWAP NEXT DROP \>> \Gb \<< { 10, } 2, 11, FOR n 0, SWAP n 2, FOR k n k COMB n k - 1, + ALOG k ALOG - 1, + * SWAP DUP n k - 1, + GET ROT * ROT + SWAP -1, STEP n DUP ALOG 9, - * ROT NEG 11, n ^ n ALOG - 10, * + SWAP / + NEXT \>> Zeta \<< 1, - DUP 1, SWAP PSI SWAP ! / DUP SIGN * \>> END << FISCHER >> TEVAL --> 22,9206766192 s:4,7817 ``` Considering Valentin's HP-71B program finds this answer in about 20 seconds this HP 50g program is somewhat slow. The beta subprogram alone takes about 2 seconds, perhaps an optimization attempt should start here. The program is just an implementation of the formula in page 2 of Thomas Schmelzer and Robert Baillie's paper: I have no idea why this formula works, however. Cheers, Gerson.

 Re: HP-71b - what to look for when buyingMessage #21 Posted by Marcel Samek on 16 Feb 2013, 8:08 p.m.,in response to message #17 by Gerson W. Barbosa I've been poking through the Challenge #19 thread and I must say that this is a pretty hard-core group here. Definitely one of the most cerebral forums I have come across!!!

 Re: HP-71b - what to look for when buyingMessage #22 Posted by Thomas Klemm on 15 Feb 2013, 9:01 p.m.,in response to message #16 by Marcel Samek Quote: With the 15c it was the sudoku solver. Just noticed you recently posted the article 1220: Sudoku Solver for the HP-15c. Thanks Thomas

 Re: HP-71b - what to look for when buyingMessage #23 Posted by Peter Murphy (Livermore) on 15 Feb 2013, 4:19 p.m.,in response to message #1 by Marcel Samek As to the various versions of the 71B, I note that that was discussed here: I note also that J-F Garnier's page about versions and bugs has been flagged as an "attack page," according to my Mac's security system, and I chose not to visit.

 Re: HP-71b - what to look for when buyingMessage #24 Posted by Massimo Gnerucci (Italy) on 15 Feb 2013, 6:30 p.m.,in response to message #23 by Peter Murphy (Livermore) I'd rather trust JFG than a Mac.:-)

 Re: HP-71b - what to look for when buyingMessage #25 Posted by J-F Garnier on 16 Feb 2013, 5:33 a.m.,in response to message #23 by Peter Murphy (Livermore) Don't use the old link to lycos (it should be just a redirection but may have been corrupted since then), use my present site at: http://www.jeffcalc.hp41.eu/ which is safe! J-F

 Re: HP-71b - what to look for when buyingMessage #26 Posted by Jerry Raia on 16 Feb 2013, 6:18 p.m.,in response to message #1 by Marcel Samek Forth/Assembler ROM for sure I think

 Re: HP-71b - what to look for when buyingMessage #27 Posted by Garth Wilson on 18 Feb 2013, 12:52 a.m.,in response to message #26 by Jerry Raia Can that one be put in the new FRAM module someone is introducing? I ask because the Forth/Assembler module has to take a fixed address space and can't be moved around the memory map like other modules can.

 Re: HP-71b - what to look for when buyingMessage #28 Posted by Hans Brueggemann on 18 Feb 2013, 4:07 a.m.,in response to message #27 by Garth Wilson Yes, FRAM71 can allocate a dedicated part of the nonvolatile RAM to a fixed address to accomodate the FORTH ROM image. Besides that, it also supports 64kByte memory blocks now. hans http://www.flickr.com/photos/75954327@N05/sets/72157630019565381/

 Re: HP-71b - what to look for when buyingMessage #29 Posted by Walter B on 18 Feb 2013, 4:25 a.m.,in response to message #28 by Hans Brueggemann Please apologize my ignorance, but does this mean that one can get access to the contents of the FORTH/ASSEMBLER module without having to pay the skyrocket prices demanded for it on TAS?

 Re: HP-71b - what to look for when buyingMessage #30 Posted by Hans Brueggemann on 18 Feb 2013, 8:04 a.m.,in response to message #29 by Walter B FRAM71 will be shipped "empty", with no pre-installed images. however, it accepts the module ROM dumps (*.DMP) that are already available with the various HP-71B emulators, as well as the system ROM dumps. hans

 Re: HP-71b - what to look for when buyingMessage #31 Posted by Walter B on 18 Feb 2013, 8:11 a.m.,in response to message #30 by Hans Brueggemann Danke! d:-)

 Re: HP-71b - what to look for when buyingMessage #32 Posted by Garth Wilson on 18 Feb 2013, 5:52 a.m.,in response to message #28 by Hans Brueggemann Excellent!

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