The Museum of HP Calculators

HP Forum Archive 20

 Atherton HP-85Message #1 Posted by David Ramsey on 3 May 2011, 12:23 a.m. I recently purchased a refurbished HP-85 from Larry Atherton. Here's what it looks like: To say it's "spotless" is an understatement. Larry refinishes the case with epoxy paint, replaces the CRT, cleans the interior, and upgrades the cassette drive. Even the bottom looks perfect. The rubber feet might not be precisely the right size, but they're brand new. Included with the computer were 4 DC100 tapes: two with the HP Standard Pac and Math Pac, and two blanks. The interior of the computer looks brand new. There is no dirt or dust anywhere. It even smells new. Even the circuit boards appear to have been washed. The printer belts are replaced, and the tape drive rebuilt as shown here: The screen is razor sharp, especially considering it's a CRT and we're all used to flat panels now: Graphics look nice, too, within the limited resolution available: And the printer is fast, silent, and otherwise perfect: Performance-wise: well, let's just say we've come a long way. Here's a simple BASIC program to find all the 3-digit numbers equal to the sum of the cubes of their digits: 10 OPTION BASE 0 @ DIM A(10) 20 FOR X = 0 TO 9 @ A(X) = X*X*X @ NEXT X 30 X = 100 40 FOR H = 1 TO 9 @ FOR T = 0 TO 9 @ FOR 0 = 0 TO 9 50 IF X = A(H) + A(T) + A(O) THEN DISP X 60 NEXT X 70 END Bracketing this code with TIME statements reveals that it takes the 85 11.757 seconds to check the numbers 100 to 999. A similar algorithm in C executes in less than a millisecond on my desktop system. Those sine curves in the graphics images? Just drawing a straight line on the screen from one corner to the other takes almost a second. Still, there's something nostalgic and attractive about this computer. I love it.

 Re: Atherton HP-85Message #2 Posted by Marcus von Cube, Germany on 3 May 2011, 2:31 a.m.,in response to message #1 by David Ramsey Nice pics! The code looks strange. The NEXT X in line 60 doesn't match any FOR statement and the three FOR statements in line 40 lack a matching NEXT. How does DIM work in line 10? M\$ BASIC would create 11 elements ranging from 0 to 10. BASIC is not C with respect to arrays.

 Re: Atherton HP-85Message #3 Posted by David Ramsey on 3 May 2011, 7:57 p.m.,in response to message #2 by Marcus von Cube, Germany Quote: Nice pics! The code looks strange. The NEXT X in line 60 doesn't match any FOR statement and the three FOR statements in line 40 lack a matching NEXT. How does DIM work in line 10? M\$ BASIC would create 11 elements ranging from 0 to 10. BASIC is not C with respect to arrays. Serves me right trying to type the code from memory. Here's the actual listing: 10 CLEAR 20 LET S=TIME 30 DISP "This is the Threez program" 40 DIM T1(10) 50 FOR X=0 TO 9 @ T1(X) = X*X*X @ NEXT X 60 C=100 70 FOR H=1 TO 9 @ FOR T=0 TO 9 @ FOR O=0 TO 9 80 IF T1(H) + T1(T) + T1(O) = C THEN DISP C 90 C=C+1 100 NEXT O @ NEXT T @ NEXT H 110 DISP "Program completed in ";TIME-S;" seconds." 120 END You're right, the DIM does allocate 11 elements, but the extra element at the end isn't used and doesn't affect the program. Hey, it's been over 20 years since I've done any BASIC!

 Re: Atherton HP-85Message #4 Posted by Marcus von Cube, Germany on 4 May 2011, 1:58 a.m.,in response to message #3 by David Ramsey Quote: Hey, it's been over 20 years since I've done any BASIC! BASIC was my first programming language, even before I encountered programmable calculators. I started at the age of 16 (now some 35 years ago) on a Wang, located in a friend's school. It was a half hour ride to get there. :-) I could never afford any HP equipment until recently. Funnily, my first encounter with a scientific calculator was an HP 35 which the very same friend lent me for a day. This triggers fond memories.

 Re: Atherton HP-85Message #5 Posted by Johnny Bjoern Rasmussen on 3 May 2011, 3:50 a.m.,in response to message #1 by David Ramsey Hi DavidCongratulations! It is absolutly perfect looking and working. I also have a HP-85 working but not at all in the same condition as yours. But you're right: It's a wonderfull machine.Cheers!Johnny

 Re: Atherton HP-85Message #6 Posted by Geoff Quickfall on 3 May 2011, 11:37 a.m.,in response to message #1 by David Ramsey Absolutely BEAUTIFUL! Reminds me that I have to get my 9825A tape drive running! Cheers and congrats, Geoff

 Re: Atherton HP-85Message #7 Posted by BobVA on 3 May 2011, 7:18 p.m.,in response to message #1 by David Ramsey Fantastic! Thanks very much for posting the photos. (Let's see. If I stopped using the stove in my apartment I could probably put one there....)

 Re: Atherton HP-85Message #8 Posted by John Robinson on 4 May 2011, 2:28 a.m.,in response to message #1 by David Ramsey Now that is a restoration !!! very impressive. I wonder where he sources new CRTs from ??? Cheers, John

 Re: Atherton HP-85Message #9 Posted by Philippe Lasnier on 4 May 2011, 8:30 a.m.,in response to message #1 by David Ramsey Ah, so it was you, David, who bought it ;-) It had been on my watch list for about a month or so and I had been dithering about whether to buy it or not (Larry has just listed another one for sale, so the dithering continues). I've got two HP-85, one working, one with self-test error, both in need of new printer belts and tape drive overhaul, but I'd really want to have a brand "new" one. Larry's ones look fantastic (just like the rest of the stuff he refurbishes does), but in my case, being in the UK, the transport cost is large, and the custom charges are horrendous! This makes it quite a decision to take. Oh well , maybe later.

 Re: Atherton HP-85Message #10 Posted by Jose Gonzalez Divasson on 3 May 2011, 5:15 p.m.,in response to message #1 by David Ramsey Atherton provided me with the QIC tape and replacement parts for the printer. Excellent service!

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