HP Forum Archive 19

[ Return to Index | Top of Index ]

What is your Holy Grail, and do you own it? Message #1 Posted by Michael de Estrada on 9 Sept 2010, 9:58 a.m. I am directing this question to those of you who regard yourselves as calculator collectors. In building my collection, I have focused on RPN LED/VFD pocket / hand held calculators, and for me the HP-35 Red Dot represents the Holy Grail as the first of the first of this genre. Several years ago I was very fortunate to acquire one of these as a complete set in perfect working condition, including all documentation tracing it to its source. Although my collection will never be complete, I feel fulfilled in owning the ultimate item. So, I ask you, what is your Holy Grail and do you own it.

Re: What is your Holy Grail, and do you own it? Message #2 Posted by Han on 9 Sept 2010, 11:10 a.m., in response to message #1 by Michael de Estrada My holy grail, unfortunately, does not exist. It would be the concept of the HP50G with the casing of an HP48GX. Said another way, imagine taking an HP48GX and giving it an ARM CPU, SD card support, USB support, flash rom, and more built-in RAM. Some long time ago, there were folks who were working on an RPN calculator casing to do more-or-less what I described above (openrpn.org?) Unfortunately, it has since disappeared.

Re: What is your Holy Grail, and do you own it? Message #3 Posted by Martin Pinckney on 9 Sept 2010, 1:41 p.m., in response to message #2 by Han Han, I would agree except in a 48sx case! However, I believe the OP is about collectibles, not what we would like to see.

Re: What is your Holy Grail, and do you own it? Message #4 Posted by M. Joury on 9 Sept 2010, 11:10 a.m., in response to message #1 by Michael de Estrada Boy, thats a tough one! I don't know that I can choose. I like the early card reader calcs (65 / 67), the 41 (of course), and I have a special liking for the HP34C (don't ask me why, I know the 15 was a better calc but I really like the looks of the 34 and the feel of it in my hand). For the same reason I like the 29C. In general I collect all / any of the RPN scientific calculators. At the moment I am missing the following: 1. HP21 2. HP25C (I have a 25) 3. HP97 4. HP32E 5. HP11C Cheers, M.J.

Re: What is your Holy Grail, and do you own it? Message #5 Posted by Norman Dziedzic on 9 Sept 2010, 11:09 a.m., in response to message #1 by Michael de Estrada Near an impossibility without a great deal of luck but mine would be my old 41CX I used in college S/N 2825S20268. Sold on TAS a long while ago...but I think it was a collector that purchased it so it still may be around somewhere. Last Known Photos 8*)

Re: What is your Holy Grail, and do you own it? Message #6 Posted by Gerson W. Barbosa on 9 Sept 2010, 12:21 p.m., in response to message #5 by Norman Dziedzic I've been lucky: some years ago I got my very first HP calculator back, the HP-15C 2343B75099, (unique dans le monde!). It had been heavily used by my younger brother during his undergraduate years and up to 2006 in the field (he's a civil engineer). Hope you'll find your unique 41CX too :-) http://www.geocities.ws/gwbarbosa/hp-15c_.jpg

Re: What is your Holy Grail, and do you own it? Message #7 Posted by Jimi on 20 Sept 2010, 5:18 p.m., in response to message #5 by Norman Dziedzic Same here. The only one I really want is the HP-41C that I had back in HS. Unfortunately for me, the last pics I had went with a bad Seagate HD years ago, so I don't even know the serial... :cry

Is there more than one Holy Grail? Message #8 Posted by Frank Boehm (Germany) on 9 Sept 2010, 11:48 a.m., in response to message #1 by Michael de Estrada 35 red dot - owned a complete one plus many prototype parts - sold Busicom LE-120A plus a couple of other Busicoms - own them Sinclair Sovereign "Silver Jubilee" - own it Sterling silver encased TI-1750 - own it Sterling silver encased Sharl EL-8009 (once belonged to Arthur Charles Nielsen) - own it ARISTO M27 without CE key - still looking for it 2 BRUNSVIGA prototype calculators - own them 9 Faber-Castell calculators, some boxed - own them plus about one hundred "Made in Germany" calculators :)

Re: What is your Holy Grail, and do you own it? Message #9 Posted by Walter B on 9 Sept 2010, 3:29 p.m., in response to message #1 by Michael de Estrada The last model I got - and thus the one which was hardest to achieve for me - was a working 91. Now I'm almost through with the objects I wanted, just very few are missing still: a working 29C, a 41C Blanknut, a working cassette drive, and last not least a 35 Red Dot (though this seems to be just one of the most expensive holes). Waiting for some extra money to spend and/or a good opportunity.

Re: What is your Holy Grail, and do you own it? Message #10 Posted by Joerg Woerner on 9 Sept 2010, 4:47 p.m., in response to message #1 by Michael de Estrada TI's '8' series! People in China traditionally associate luck with numbers. As a rule in day-to-day life in China, it is customary to regard even numbers as being more auspicious than odd numbers. Eight, 'Ba' in Chinese has a similar sound to 'Fa', which means to make a fortune. All business men favor this number very much. However, for Texas Instruments the "8" in the type designation was not always a fortune. TI-18: Own it TI-38: Own it TI-78: Own it TI-88: Own it Regards, Joerg

Re: What is your Holy Grail, and do you own it? Message #11 Posted by db (martinez, ca.) on 9 Sept 2010, 8:28 p.m., in response to message #10 by Joerg Woerner Joerg: I can see why your list ends with the incredible TI-88. It would have been a very impressive machine if it would have been sold (and with a better keyboard). But it wasn't, because hp introduced the real Holy Grail; the 41 series.

Re: What is your Holy Grail, and do you own it? Message #12 Posted by Manatee on 9 Sept 2010, 5:04 p.m., in response to message #1 by Michael de Estrada For me it's the 25C. It was my first HP, when I was a teen. I lost track of it sometime after it stopped working. I didn't realize at the time that it would hold such meaning for me. I've picked up a bunch of other HPs over time -- 65, 67, 41CX, 12C among my favorites, but I haven't managed to hit on a 25C in the condition I'd like. The Woodstocks in general are my favorite series, and the only one I have is a lowly 21. Seems there just aren't many survivors.

Re: What is your Holy Grail, and do you own it? Message #13 Posted by Bruce Bergman on 9 Sept 2010, 8:53 p.m., in response to message #12 by Manatee I agree Manatee! (rhymes, doesn't it?) The 25c was my first "personal" HP calculator, and although I have a fondness for many other HP calculators, I somehow bonded with that first HP and always get teary-eyed when I pull it out. Fortunately, mine is still working. I do like the 34c too, and of course, my favorite collectible was my 19c (also still working and prints). Fond memories. Thanks, Bruce

Re: What is your Holy Grail, and do you own it? Message #14 Posted by Palmer O. Hanson, Jr. on 9 Sept 2010, 5:48 p.m., in response to message #1 by Michael de Estrada I have five: The first is my K&E Log Log Duplex Decitrig purchased in 1947. The second is my Addometer, a rotary adder manufactured by Reliable Typewriter and Adding Machine Co. Built like a truck! The third is my Faber-Castell 67/22R which is a 12.5 cm slide rule with an Addiator on the back. The fourth is my Canon Pocketronic which uses a paper taper output and was based on TI's Cal Tech. Mine came with a Hi-speed Battery Charger -- would you believe 20 amperes! Unfortunately, my unit isn't operational due to some substantial cell leakage. The fifth is my Radio Shack Model 100. Fourteen digit arithmetic and a 240x64 pixel LCD plotting capability long before the advent of the fx-7000G or HP-27C. Palmer

Re: What is your Holy Grail, and do you own it? Message #15 Posted by Dallas Osborne on 9 Sept 2010, 7:24 p.m., in response to message #14 by Palmer O. Hanson, Jr. 42s I gots me 8 of them. 7 are vacuum packed. I believe in redundancy... you know, just in case.

Re: What is your Holy Grail, and do you own it? Message #16 Posted by Michael Plant on 9 Sept 2010, 8:20 p.m., in response to message #14 by Palmer O. Hanson, Jr. HP-42s - own two, one MIB HP-41CV - own it TI-55II - own several. This was THE calculator when I was in middle school and I wanted one desperately. I thought my father was nuts going on about the HP-15c at the time Casio fx-603p - own it Aristo 0972 - own it Dietzgen N1725 - own two K&E 4081-3 - own three (two circa 1947 and one circa 1955 - scales are different) Still on my list an HP-65 or a 67, and an HP-71b. If I had to pick two Holy Grails, though, they'd be the Aristo 0972 and the Casio fx-603p. I waited a long time for each of them. This was a useful exercise. I own 82 electronic calculators and 43 slide rules and having to pick the most important to me means that I can see that there are an awful lot of them that I could probably divest myself of if I weren't so darned lazy... Edited: 9 Sept 2010, 9:30 p.m.

Re: What is your Holy Grail, and do you own it? Message #17 Posted by Palmer O. Hanson, Jr. on 9 Sept 2010, 10:07 p.m., in response to message #16 by Michael Plant Michael: You wrote: Quote: TI-55II - own several. This was THE calculator when I was in middle school and I wanted one desperately. I thought my father was nuts going on about the HP-15c at the time Didn't you have problems with the keyboard? TI eventually had a program where one could send in a 55II, and with no questions asked, get a 55III with an improved keyboard in return. I have two K&E 4081-3's but hadn't noticed a difference in the scales. I will have to look at them when i am in Florida next week. My serial numbers are 365144 (the one I purchased in 1947) and 279673 (which I purchased at an estate sale) which I assume was an earlier model due to the lower serial number. I forgot to mention one holy grail that I don't have -- a Friden which calculates square roots. I have two other earlier Fridens including one manual. Palmer

Re: What is your Holy Grail, and do you own it? Message #18 Posted by Michael Plant on 10 Sept 2010, 12:27 a.m., in response to message #17 by Palmer O. Hanson, Jr. Hi Palmer, My two 1940's vintage 4081-3s both have the following scales: Front: LL0, LL00, A, [ B, T, ST, S, ] D, DI, K Back: L, LL1, DF, [ CF, CIF, CI, C, ] D, LL3, LL2 The serial numbers are 382813 and 414326 and they date to 1945/6. Both these slide rules have solid celluoid covered edges. The other one is serial number 393487 (apparently K&E reset the serial numbers every so often) and it has mahogany edges with inlaid celluloid - what Walter Shawlee at Sphere Research calls "relieved wood" edges (there's a picture of this here http://www.sliderule.ca/ken408e.jpg). The Dietzgen 1734 and N1725 have the same edging. The scales on this slide rule are: Front: LL01, L, K, A, [ B, T, SRT, S, ] D, DI, LL1 Back: LL02, LL03, DF, [ CF, CIF, CI, C, ] D, LL3, LL2 BTW, when dating a K&E slide rule, you have to look at the serial number, the scale sets, and the patent dates: http://www.sliderulemuseum.com/?PHPSESSID=f37c9f3c94a451c50eb872a57e936cf6 (see K&E entry) and http://www.mccoys-kecatalogs.com/Dating.htm Regarding the TI-55II, yes, I don't have a single example of ANY of the TI's from that era (TI-57 LCD, TI-54, TI-55II) with a 100% functioning keyboard. The TI-55III that I have still works flawlessly, but it is lighter, smaller, and doesn't have the solid "quality" feeling that the TI-55II has... Funny, the Casio fx-570 that I had in middle school, and which I used grudgingly while salivating over a friend's TI-55II, looks and functions like it's new. Comparing them now, it seems to be more feature rich, too! I was quite disappointed when I finally got a TI-55II a couple of years ago and couldn't actually use it!

Re: What is your Holy Grail, and do you own it? Message #19 Posted by Gerson W. Barbosa on 10 Sept 2010, 4:53 p.m., in response to message #14 by Palmer O. Hanson, Jr. Quote: The fifth is my Radio Shack Model 100. Fourteen digit arithmetic and a 240x64 pixel LCD plotting capability long before the advent of the fx-7000G or HP-27C. It looks like the ATN function was not accurate for arguments close to (2-sqrt(3)) and 1, unless there was an improved ROM: print 12*atn(2-sqr(3));4*atn(1) 3.1415926524007 3.1415926531932 My old MSX computer, which had more a recent Microsoft Basic version, returns 3.1415926535908 3.1415926535898 Forensic result: 10 CLS 20 K=ATN(SQR(3))/60 30 F=ATN(TAN(COS(SIN(9*K)*K)*K))/K 40 X=F: GOSUB 200: F=X 50 X=F: GOSUB 100: F=X 60 PRINT F 70 END 100 X=ATN(X/SQR(1-X*X))/K 110 RETURN 200 X=ATN(SQR(1-X*X)/X)/K 210 RETURN 8.9999999712261 On the MSX I get 8.9999999710834 Gerson. Edited: 10 Sept 2010, 4:56 p.m.

Re: What is your Holy Grail, and do you own it? Message #20 Posted by Palmer O. Hanson, Jr. on 11 Sept 2010, 11:24 p.m., in response to message #19 by Gerson W. Barbosa Gerson: You wrote: Quote: It looks like the ATN function [of the Model 100} was not accurate for arguments close to (2-sqrt(3)) and 1, unless there was an improved ROM: print 12*atn(2-sqr(3));4*atn(1) 3.1415926524007 3.1415926531932 The problem with that method is that you are evaluating the ATN function AND the ability of the machine to calculate 2 - sqrt(3). I don't have my Model 100's here but consider the results from two machines of similar vintage, the HP-41 and TI-59. If you just do the equivalents of 12*atn(2-sqr(3)) on those machines you will get pi 3.1415 92653 58979 ... HP41 3.1415 92649 TI59 3.1415 92653 6 But 2-sqr(3) = .26794 91924 3112 ... and if you enter the first ten digits into the display register of either machine, take the atn and multiply by 12 you will get pi 3.1415 92653 58979 ... HP41 3.1415 92654 TI59 3.1415 92653 24 and if you enter thirteen digits into the TI-59 display register by entering .2679491924 + 3.11E-11 = you will get pi 3.1415 92653 58979 ... TI59 3.1415 92653 588 I will have access to my Model 100's next week. The serial numbers are 30208973 and 309012942. The unit with the first serial number was one of the first Model 100's to be made available in our county. Palmer

Re: What is your Holy Grail, and do you own it? Message #21 Posted by Gerson W. Barbosa on 12 Sept 2010, 10:38 a.m., in response to message #20 by Palmer O. Hanson, Jr. Palmer, Quote: The problem with that method is that you are evaluating the ATN function AND the ability of the machine to calculate 2 - sqrt(3). You are right, 12*ATN(.2679491924311) is better, albeit only slightly: 3.1415926547795 However, there is indeed a problem with ATN( ) in Model 100, at least in the ROM version Virtual T Emulator currently uses. That's why I had to resort to ATN(SQR(3))/60 for pi/180 instead of ATN(1)/45. When the emulator is set to Model 102, I obtain the same results I get on the MSX computer: 4*ATN(1) -> 3.1415926535898 12*ATN(.2679491924311) -> 3.1415926535896 12*ATN(2-SQR(3)) -> 3.1415926535908 Gerson. Edited: 12 Sept 2010, 10:41 a.m.

Re: What is your Holy Grail, and do you own it? Message #22 Posted by Palmer O. Hanson, Jr. on 12 Sept 2010, 11:04 a.m., in response to message #21 by Gerson W. Barbosa Gerson: Quote: However, there is indeed a problem with ATN( ) in Model 100, at least in the ROM version Virtual T Emulator currently uses. That's why I had to resort to ATN(SQR(3))/60 for pi/180 instead of ATN(1)/45. You are correct in that there is a problem of some magnitude with ATN. I had successively used 4*ATN(1) in radian mode as a way to generate pi with a number of BASIC implementations, but it didn't yield the accuracy that I needed on the Model 100. I found another method but can't for the present remember what it was. I will find it next week and post it here. Palmer

Re: What is your Holy Grail, and do you own it? Message #23 Posted by Gerson W. Barbosa on 12 Sept 2010, 9:41 p.m., in response to message #22 by Palmer O. Hanson, Jr. Palmer, I found the problem: someone made a small mistake when typing one of the coefficients of the arctangent polynomial. It should be -0.14285708554884 instead of -0.14285608554884. PEEK(13247) returns 86 (56h), it should return 87 (57h). The fix should be easy (just a matter of changing the content of memory address 33BFh from 56h to 57h), but I don't know if a compatible 32K ROM or EPROM is still available. http://upload.wikimedia.org/wikipedia/commons/5/55/TRS-80_Model-100_Inside.jpg When I edited the Model 100 ROM in the emulator, the results mached those of the MSX computer. Likewise when I changed the corresponding memory address (2E54h) in the MSX computer from 57h to 56h the arctangent function started behaving exactly like it does on the Model 100. Gerson.

Re: What is your Holy Grail, and do you own it? Message #24 Posted by Gerson W. Barbosa on 21 Sept 2010, 1:02 a.m., in response to message #22 by Palmer O. Hanson, Jr. Palmer, Here is a workaround: 10 CLS:INPUT TH 15 PI=2*ATN(3E13):SR3=1.7320508075689:S1=SGN(TH):X=ABS(TH) 20 IF X<1 THEN K1=0:S2=1 ELSE X=1/X:K1=PI/2:S2=-1 25 IF X>(2-SR3) THEN X=(X*SR3-1)/(X+SR3):K2=PI/6 ELSE K2=0 30 Y=S1*(K1+S2*(K2+ATN(X)-1E-6*X^7)) 35 PRINT Y It should give correct results all through the valid range, except for |TH| = 1 and 1-10^-14: TH ATN(TH) 0.00 0.00000000000000 -0.15 -0.14888994760950 0.20 0.19739555984988 0.30 0.29145679447789 0.60 0.54041950027057 1-1E-13 0.78539816339739 1.05 0.80978357257017 -3.75 -1.31019393504750 8.15 1.44870718939760 -1000.00 -1.56979632712820 1-1E-14 0.78539816319912 (0.78539816339744) 1 0.78539816359578 (0.78539816339745) Further tests may be required. Regards, Gerson. Edited to correct a typo in line 30. Edited: 21 Sept 2010, 5:39 p.m.

Re: What is your Holy Grail, and do you own it? Message #25 Posted by Thomas Radtke on 10 Sept 2010, 3:07 a.m., in response to message #1 by Michael de Estrada The 35 without that silly red dot ;-). Really, I'm satisfied with my used and not-so-rare sample. It is in its original hard case and with all accessories, which was a must when I wanted to get one. Still wondering how to present it on the shelf in its case half opened without destroying the case.

Re: What is your Holy Grail, and do you own it? Message #26 Posted by Giovanni Jimenez on 10 Sept 2010, 5:45 p.m., in response to message #25 by Thomas Radtke How much is a HP-35 Red Dot ? I keep reading how rare it is, but how $$ rare is it ?

Re: What is your Holy Grail, and do you own it? Message #27 Posted by Michael de Estrada on 10 Sept 2010, 6:51 p.m., in response to message #26 by Giovanni Jimenez Based on recent history, I'd say that an HP-35 Red Dot that is authentic (there have been fakes), fully functional, original (not repaired or modified) and with all original accessories will fetch at least $1000 on the world market. However, since there have not been any public auctions such as TAS for several years, next time this happens the price could be much higher. It all depends on how much any collector is willing to pay. I've seen the HP-01 sell for over $5000 USD, and to me the HP-01 is a less significant milestone than the HP-35 Red Dot. Edited: 10 Sept 2010, 7:08 p.m.

Re: What is your Holy Grail, and do you own it? Message #28 Posted by Steve Leibson on 10 Sept 2010, 4:32 a.m., in response to message #1 by Michael de Estrada HP 9825A Desktop Calculator/Computer with Systems Programming ROM - because I designed interface cards for the 9825A and I wrote the ROM. Have a few, one with a working refurbed tape drive. All from eBay bought 30 years after the fact.

Re: What is your Holy Grail, and do you own it? Message #29 Posted by John Mosand on 10 Sept 2010, 7:10 a.m., in response to message #28 by Steve Leibson A mint Curta, an Aristo 0972 HyperLog and yes, a HP-10C. I have those + about 80 different Aristo slide rules, and two Aristo calculators, M65 and M76. (My everyday user is a HP-48SX with an EquLibrary card and a MathPac card.)

Re: What is your Holy Grail, and do you own it? Message #30 Posted by JMBaillard on 10 Sept 2010, 4:43 p.m., in response to message #29 by John Mosand An HP-41CX with 1MB RAM and a turbo mode ( or several choices of speed ) Jean-Marc.

Re: What is your Holy Grail, and do you own it? Message #31 Posted by Antoine M. Couëtte on 11 Sept 2010, 1:27 p.m., in response to message #30 by JMBaillard Jean-Marc, I have currently ran such a device for some 5 years ! It actually has much more than 1 Mb : simply the Wonderful "HP41X/Y/Z" HP41 Emulator running on HP48GX by HrastProgammer. I have almost never used my old trusty HP41CX since 2005. Best Regards Antoine Antoine M. "Kermit" Couëtte

Re: What is your Holy Grail, and do you own it? Message #32 Posted by JMBaillard on 11 Sept 2010, 5:22 p.m., in response to message #31 by Antoine M. Couëtte Hi Antoine, HP41/X/Y/Z is surely a great emulator, but I'm attached to my "true" HP-41, its keyboard... All the Best, Jean-Marc.

Re: What is your Holy Grail, and do you own it? Message #33 Posted by Monte Dalrymple on 11 Sept 2010, 11:15 p.m., in response to message #32 by JMBaillard Ditto on the 41 keyboard. Oh, and I do have a 41 with 256kx16 RAM and 1Mx16 Flash... but it's the only one in existence right now. Monte

Re: What is your Holy Grail, and do you own it? Message #34 Posted by Massimo Gnerucci (Italy) on 12 Sept 2010, 7:28 a.m., in response to message #33 by Monte Dalrymple Monte, Monte... the tantalizing Monte... ;-) Greetings, Massimo

Re: What is your Holy Grail, and do you own it? Message #35 Posted by JMBaillard on 12 Sept 2010, 5:25 p.m., in response to message #33 by Monte Dalrymple Really ? Did you build this wonder by yourself? I know - but I don't own - Diego's NOVRAM but 1MB ? Effectively tantalizing...

Re: What is your Holy Grail, and do you own it? Message #36 Posted by Monte Dalrymple on 12 Sept 2010, 9:02 p.m., in response to message #35 by JMBaillard You might review this thread: http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv019.cgi?read=168952#168952

Re: What is your Holy Grail, and do you own it? Message #37 Posted by JMBaillard on 13 Sept 2010, 5:36 p.m., in response to message #36 by Monte Dalrymple Hi Monte Thank you for the link, I had not remarked it before. If it is ( or will be ) possible to purchase it, would you please give us an idea of the price for this super-coconut ? All the Best, JMB.

Re: What is your Holy Grail, and do you own it? Message #38 Posted by Antoine M. Couëtte on 12 Sept 2010, 9:14 a.m., in response to message #32 by JMBaillard Hello Jean-Marc, Obviously the "True keyboard" of a "True" HP41 cannot be beaten in any way : I fully agree with you on this point. However, and from experience five years ago then, I can state that after just a couple of weeks of regular use ("far too long a transition time" might you quite rightfully think) I have become as fluent with the HP48 keyboard than with the HP41 "ideally perfect" one. I had no choice then : either quit or continue with HrastProgrammer's HP41X/Y/Z Emulator !!! Anyway, it is absolutely wonderful to observe how much enthusiam such a wonderful machine keeps raising all over the world !!! Have a great and sunny day and Best Regards to all Antoine Antoine M. "Kermit" Couëtte

Re: What is your Holy Grail, and do you own it? Message #39 Posted by JMBaillard on 12 Sept 2010, 5:29 p.m., in response to message #38 by Antoine M. Couëtte Hello Antoine, In fact, most of my HP48GX keys don't respond anymore, wheras the 41 keys still work well! So, the choice is easy to do... Best wishes, Jean-Marc.

Re: What is your Holy Grail, and do you own it? Message #40 Posted by Michael Meyer on 10 Sept 2010, 11:18 p.m., in response to message #1 by Michael de Estrada I own almost every model of HP calculators. I finally got a 10C just today. Still missing an HP-70 and a 75 and a 92 and a 33C and 21S and 27S. My Holy Grail? Still the HP-25. My, "first love." I "lusted" after HP's and girls when I was in 8th grade. It was a time of discovery and imagination. My HP-25 was stolen after I got my TI-59. Today I have about 6 HP-25's (assembled from the best parts of many more). I just can't resist buying and restoring them. I doubt my wife would let me collect any girls.

Re: What is your Holy Grail, and do you own it? Message #41 Posted by Thomas Okken on 11 Sept 2010, 2:43 a.m., in response to message #1 by Michael de Estrada Aren't "having a Holy Grail" and "being a collector" somewhat contradictory? I mean, either you want one item in particular, or you want them all -- those seem like very different kinds of motivation to me. I consider myself a big fan of HP calculators, but I'm not much of a collector. My "Holy Grails" are the HP-25 (my first!), HP-67 (really, really wanted one back in the day but couldn't afford it), HP-42S (best RPN ever), and the HP-48G (truly a hand-held computer). I have one of each of those holy grails. I love the HP-67 the most, even though I never use it. :-)

Re: What is your Holy Grail, and do you own it? Message #42 Posted by Michael de Estrada on 11 Sept 2010, 9:24 a.m., in response to message #41 by Thomas Okken Quote: Aren't "having a Holy Grail" and "being a collector" somewhat contradictory? I mean, either you want one item in particular, or you want them all -- those seem like very different kinds of motivation to me. I see no contradiction. I want to collect many noteworthy vintage calculators, but I rank one above the rest as being the most significant historically. I don't want all the calculators ever made, but most of those that fit a certain category. In my case that category is RPN, pocket / hand held. I value most those that represent milestones, such as the HP 35 Red Dot (first of the first), HP 65 (first programmable with storage), HP 25c (first CMOS memory), HP 41C (too many firsts to list here). I value them all, but I regard the HP 35 Red Dot as the most significant and essential to a proper collection. My collection is complete in some areas and not so in others. I have all the Classics, Woodstocks and Spices, but am missing many of the later models. I will continue to collect, however, I do not have a compulsion to acquire at any cost, whereas, if I did not have my Holy Grail, I would have an almost insane drive to find one at any cost.

Re: What is your Holy Grail, and do you own it? Message #43 Posted by Mike T. on 11 Sept 2010, 9:52 a.m., in response to message #1 by Michael de Estrada Difficult for me to decide between the HP29C or the HP67, but if I had a the option I would probably choose an HP29C - unfortunately I own neither.. It isn't all bad though I do own an HP10C which I brought in 1986 to replace my first HP33C when it broke, and I did eventually manage to get another HP33C which I still use regularly. I did find that when it came to programming the HP10C was always a bit of a disappointment, even though it had more program steps available than the HP33C. Mike T. Edited: 11 Sept 2010, 9:57 a.m.

Re: What is your Holy Grail, and do you own it? Message #44 Posted by Michael de Estrada on 11 Sept 2010, 10:33 a.m., in response to message #43 by Mike T. I own the HP 29C and HP 67, as well as the HP 33C. I use the HP 29C a fair amount, but have ported all my HP 67 programs via card reader to my HP 41CV. The HP 33C doesn't get used much, since I have an HP 34C. I've never owned an HP 10C, since I've had an HP 15C for 28 years, and have never seen the need for an HP 10C.

Re: What is your Holy Grail, and do you own it? Message #45 Posted by Michael Meyer on 11 Sept 2010, 10:57 a.m., in response to message #44 by Michael de Estrada I don't think anybody has a need or use for a 10C... that's why it's somewhat rare and needed to complete a collection of Voyagers. I use a beat-up, $40 15C, but the mint one is 'with the Voyagers.' (I guess that might differentiate a collector/user from a user... the collector/user uses the less pristine example and keeps the "good one" put away...)

Re: What is your Holy Grail, and do you own it? Message #46 Posted by Maximilian Hohmann on 12 Sept 2010, 2:50 p.m., in response to message #1 by Michael de Estrada Hello! I have thought about this answer for quite some time. To me, a holy grail is something that is highly desirable, but (probably) nonexistent in reality. Something, that I will be chasing for the next 50 years (or whatever time I have left). Therefore, _my_ holy grail is the one (vintage) pocket calculator with a green LED display. We have been discussing this topic before, but there must be one somewhere. At least a prototype! Of my other holy grails in terms of mobile computers (certainly not a pocket computer!) at least six lie uncollected and unclaimed on the surface of the moon, ready to be picked up: The Apollo Guidance Computer. I would trade my house for one of them (but don't tell my wife...)! And I would trade even more for the ride to go up there and search for it. Regards, Max

Re: What is your Holy Grail, and do you own it? Message #47 Posted by Don Shepherd on 12 Sept 2010, 5:14 p.m., in response to message #46 by Maximilian Hohmann Quote: at least six lie uncollected and unclaimed on the surface of the moon Max, was the AGC stored in the descent stage? That's the only thing that was left on the moon, right? Wouldn't the astronauts have needed the AGC to rendevous with the command module after landing on the moon? If so, then those computers (in the ascent stage of the LM) have either burned to a crisp during eventual Earth re-entry of the ascent stage or are still orbiting the Earth somewhere. You'd have better luck stealing one from a museum!

Re: What is your Holy Grail, and do you own it? Message #48 Posted by Maximilian Hohmann on 13 Sept 2010, 2:24 a.m., in response to message #47 by Don Shepherd Hello! Quote: Max, was the AGC stored in the descent stage? That's the only thing that was left on the moon, right? Wouldn't the astronauts have needed the AGC to rendevous with the command module after landing on the moon? If so, then those computers (in the ascent stage of the LM) have either burned to a crisp during eventual Earth re-entry of the ascent stage or are still orbiting the Earth somewhere. Unfortunately, they were part of the ascent stages. One of them Aquarius/Apollo 13 has burnt up in Earth atmosphere, but six others (Apollo 11, 12, 14, 15, 16 and 17) have impacted the moon in more or less well known locations. The units were quite solidly packaged (http://ed-thelen.org/comp-hist/TheCompMusRep/TCMR-V02-P05b.jpg), but of course the impacts occurred at high speed (1.5 km/s). But aren't we well trained to combine the remains of several defective calculators into a single working one ;-) ? Regards, max

Re: What is your Holy Grail, and do you own it? Message #49 Posted by Mike Morrow on 13 Sept 2010, 7:17 a.m., in response to message #48 by Maximilian Hohmann Don't forget about Snoopy (LM-4) from the May 1969 Apollo 10 mission. The LM-4 ascent stage is still in solar orbit, presumably intact, after more than 41 years. It's the only flight LM that's still in flight. Though LM-4 did not land on the moon, its descent stage was allowed to impact the surface and the upper stage was put in solar orbit. The Apollo Guidance Computer (AGC) is a fascinating device. There was one AGC in the Command Module and one in the Lunar Module. So several more AGCs should still exist, one where ever any of the returned CMs are located today.

Re: What is your Holy Grail, and do you own it? Message #50 Posted by Paul Guertin on 13 Sept 2010, 4:42 p.m., in response to message #49 by Mike Morrow Quote: The Apollo Guidance Computer (AGC) is a fascinating device. ISBN-10: 1441908765 is a new book by Frank O'Brien about the AGC. It contains 100% of your daily recommended portions of acronyms.

Re: What is your Holy Grail, and do you own it? Message #51 Posted by Don Shepherd on 13 Sept 2010, 8:25 a.m., in response to message #48 by Maximilian Hohmann Oh, OK, thanks Max. From the Apollo 13 movie I knew that jettisoning the LM was the last thing they did prior to re-entry, but of course that's because they needed the LM to get home! After 13, I wonder why in later missions they didn't keep the LM attached until approaching Earth, in case the command module had some sort of problem.

Re: What is your Holy Grail, and do you own it? Message #52 Posted by Jeff O. on 13 Sept 2010, 4:17 p.m., in response to message #51 by Don Shepherd Quote: After 13, I wonder why in later missions they didn't keep the LM attached until approaching Earth, in case the command module had some sort of problem. That's a good question. My hope is that they evaluated all possible failure scenarios and determined that the LM ascent stage would do no good in any of them and/or outweigh any risks of keeping the LM attached. Scenarios that come to my mind: Service Module main engine fails to burn to get them out of lunar orbit and on their way back to earth. LM ascent engine too weak and/or not enough fuel to do the job, crew is doomed anyway, so jettison LM. Service Module main engine gets them out of lunar orbit and on their way back to earth, but then fails so it cannot make any needed course correction burns for safe re-entry. LM ascent engine too weak and/or not enough fuel to do the job, crew is doomed anyway, so jettison LM. Service Module suffers some problem, let’s say it’s punctured by a micro-meteor, on their way back to earth. Presume this prevents it from being used for re-entry, so even if they could use the main engine to get into earth orbit (I have no idea if the main engine had the capability to do this), probably not enough oxygen left on board to keep them alive in the LM long enough to mount a rescue mission from earth, crew is doomed anyway, so jettison LM. Note that for 1 and 2, I do not know the capabilities of the LM engine, I am just postulating. ...

Re: What is your Holy Grail, and do you own it? Message #53 Posted by Don Shepherd on 13 Sept 2010, 4:51 p.m., in response to message #52 by Jeff O. Jeff, I wrote Sy Liebergot, EECOM for Gene Kranz's team, and asked him this. He said: most of the LM consumables would have been used up. As you alluded to. Don

Re: What is your Holy Grail, and do you own it? Message #54 Posted by Juergen Keller on 12 Sept 2010, 6:29 p.m., in response to message #46 by Maximilian Hohmann Your definition is good. But the Holy Grail is also something that changes its shape over time. In the beginning, it is something not so rare, and after you have found your first Holy Grail, there is suddenly another which is, of course, harder to find. And so on, and so on. After a long collector's career, you end up like Max who has to build its own rocket and fly to the moon to find another Holy Grail, just to realize that there is something even more interesting than an Apollo Guidance Computer ;-) Anyway, one thing is for sure: searching for the Holy Grail is MUCH fun! Enjoy, Juergen

something like this? Message #55 Posted by Frank Boehm (Germany) on 13 Sept 2010, 6:38 a.m., in response to message #54 by Juergen Keller Quote: just to realize that there is something even more interesting than an Apollo Guidance Computer You mean something like this? Guidance computer Edited: 13 Sept 2010, 8:53 a.m.

Re: something like this? Message #56 Posted by Juergen Keller on 13 Sept 2010, 2:02 p.m., in response to message #55 by Frank Boehm (Germany) That would probably be the ultimate challenge!

Re: something like this? Message #57 Posted by Dave Shaffer (Arizona) on 13 Sept 2010, 10:21 p.m., in response to message #56 by Juergen Keller We just wait a few hundred thousand years for some little green (wo)men to bring it back!

Re: something like this? Message #58 Posted by Maximilian Hohmann on 14 Sept 2010, 3:12 a.m., in response to message #57 by Dave Shaffer (Arizona) Quote: We just wait a few hundred thousand years for some little green (wo)men to bring it back! Much easier: One of the geniusses here who have mastered RPL programming (certainly not me) should easily be able to figure out how to build a warp drive!

Re: something like this? Message #59 Posted by Walter B on 14 Sept 2010, 4:09 a.m., in response to message #58 by Maximilian Hohmann Though I didn't master RPL either so far, if you give me a (metric!) ton of green Kryptonium, you'll get your warp drive by the end of the year. Please specify the connecting dimensions asap.

Re: What is your Holy Grail, and do you own it? Message #60 Posted by Geir Isene on 14 Sept 2010, 7:00 a.m., in response to message #1 by Michael de Estrada Still looking for a nice and working HP-27. Apart from that: An HP-41CX in aluminum casing (or a NEWT in such casing)

Re: What is your Holy Grail, and do you own it? Message #61 Posted by Michael de Estrada on 14 Sept 2010, 2:36 p.m., in response to message #60 by Geir Isene Quote: Still looking for a nice and working HP-27 Undoubtedly one of the most elusive vintage HP models. I was lucky enough to find one about a year ago that was in perfect working condition, but that had been butchered by the previous owner with engravings on the case and display. The case was easily swapped out with a clean one from another Woodstock, but I have to live with display engraving, which fortunately is small and below the line of sight to the led's. IIRC, another clean and working HP-27 sold about a month later as part of a very large collection for close to $500. Just a short time ago, an HP-70 sold for $680, making it another highly coveted vintage HP model. The only model I don't own that I'd really want is the HP-95C, but I think I'd have be part of the inner circle of HP enthusiasts that inhabit this forum to get my hands on one.

Another HP 27 auction Message #62 Posted by Michael de Estrada on 14 Sept 2010, 4:36 p.m., in response to message #61 by Michael de Estrada Just as I finished speaking of the rarity of the HP-27, another one pops up on TAS. I truly love the seller's description: "You are bidding on an Hewlett Packard, HP-27, Financial Calculator with case. It appears to be in really nice shape. However, I do not have the power supply to test it. My experience is that these were built like tanks and always work."

Re: Another HP 27 auction Message #63 Posted by Mark Edmonds on 20 Sept 2010, 5:29 p.m., in response to message #62 by Michael de Estrada Doesn't seem much interest in the early desktops - holy grail for me is a 9100B with printer but a full collection of all the 98xx desktops would make me pretty happy! Sadly funds totally preclude any collecting at the moment and I doubt anyone is throwing out 9100s! I still check the charity shops though :) (And would be decent about it if lightning did strike).

Re: Another HP 27 auction Message #64 Posted by Juergen Keller on 21 Sept 2010, 3:43 a.m., in response to message #63 by Mark Edmonds I am interested in the early desktops, and I own a 9100A and B, the A with printer, the B with extended memory and plotter. Both are in fully working condition and in pretty good shape :-)

Re: Another HP 27 auction Message #65 Posted by Mark Edmonds on 21 Sept 2010, 7:02 a.m., in response to message #64 by Juergen Keller Fantastic! :) Do you use them at all? Are they rugged enough to stand regular use or really of the age that makes them museum pieces only?

Re: Another HP 27 auction Message #66 Posted by Juergen Keller on 21 Sept 2010, 4:46 p.m., in response to message #65 by Mark Edmonds Yes, I use them but just for fun. The 9100A I got recently and the first task will be to clean it. Regarding the 9100B I still work on fixing the plotter, everything else works fine. If I manage to get the plotter running I will program some drawing programs. Also planned is a short Youtube movie but currently I just have not enough spare time for that. At least I took some pictures.

Re: Another HP 27 auction Message #67 Posted by Walter B on 21 Sept 2010, 5:51 p.m., in response to message #66 by Juergen Keller Grüezi Jürgen, great stuff! How is the orange display of register labels done? If these are fixed labels a simple light bulb would do ... Beste Grüsse, Walter

Re: Another HP 27 auction Message #68 Posted by Juergen Keller on 22 Sept 2010, 3:21 a.m., in response to message #67 by Walter B Hi Walter, it's done by the coloured plastic of the display (or a coloured foil mounted to the display, I don't remember exactly) and two simple light bulbs. When I touched the bulbs the lower part (the screw thread) just crumbled due to age. Thanks to eBay I got some new ones, and of course some spare ones. If you pass by the Bodensee, you are welcome to play with my 'babies' :-) Best Regards, Juergen

Re: Another HP 27 auction Message #69 Posted by Mark Edmonds on 26 Sept 2010, 12:53 p.m., in response to message #68 by Juergen Keller Looks like a great unit Juergen :) I've never seen that rack unit before - is that the memory expansion? Seems a bit large for it even by that vintage.

Re: Another HP 27 auction Message #70 Posted by Juergen Keller on 26 Sept 2010, 3:18 p.m., in response to message #69 by Mark Edmonds Yes, it is the HP 9101A Extended Memory unit. And it has to be that large because it provides additional 3472 program steps or 248 data registers ;-) (the 9100B has 32 storage registers built-in, which are 392 program steps).

Re: Another HP 27 auction Message #71 Posted by Mark Edmonds on 29 Sept 2010, 8:15 a.m., in response to message #70 by Juergen Keller OK, thanks :) I don't suppose you've taken any pictures inside the memory expansion unit? That could be amazing to see!

Re: Another HP 27 auction Message #72 Posted by Juergen Keller on 29 Sept 2010, 2:20 p.m., in response to message #71 by Mark Edmonds Yes, I did, but I didn't yet have time to put it onto flickr. Drop me a mail, and I will send you some pictures :-)

[ Return to Index | Top of Index ]

Go back to the main exhibit hall