I have been looking at the HP35s (anniversary edition) which ofcourse commerates the original HP35 released in the early 70s.

It looks a nice machine which is keystroke programmable in both RPN and AOS but interestingly offers no linking option to a PC. There is infact no way to store programs other than in volatile memory (32kb) and worse still there are reports of buggy firmware which causes the machine to hang mid program.

Does anyone have one of these calculators and would there be a hardware to include an interface to SD card ?

What were HP thinking ?

I have this calculator.
It is absolutely gorgeous outside and absolutely dumb inside. A blond of calculator world.
Total disappointment.

Absense of SD and PC link is not a problem in my opinion. But firmware cannot be replaced -- i think i read on hp forum that it is in "programmable once" rom -- and bugs and overall stupidity of it make it barely useable.

Yes - I think HP have neglected the calculator market that they essentially founded. There are some great case histories of scientists "saving the world" with a HP35. NASA took one into space as a backup. I think there may be a little snobbery involved too particularly regarding the use of RPN. I read somewhere of someone refering to TI's machines as "toys"....

Care to share links?
Would love to read about it.

Take a look at these links:
http://www.iceinspace.com.au/forum/showthread.php?t=86265
http://www.hp.com/hpinfo/newsroom/press/2007/070712b.html
http://www.ti59.com/rcl20.htm

i wish i had an HP calc, but no.

maybe HP sent an incomplete version to be mass produced, and only realised their mistake after it was in stores?

If you are still looking for a simple programmable,
I picked up an HP-30b a few days ago from ebay for less than $20 and absolutely love it so far.
Don't let the designation "business professional" put you off. Yes, it has some weird stuff like Black-Scholes stock pricing menu, but the rest is pretty impressive.
Of non-"business professional" stuff it has:
10 named registers (0..9)
100 indexed by reg0 registers (shared with cash flow and statistics)
trigs
hyperbolics
IP,FP,exp,ln,gamma,c(m,n),p(m,n)
cdf and inverse distributions (normal,chi2,F,t)
random numbers with assignable seed
linear,power,exp,log,quadratic regressions
RPN (optional, if you are RPNophobe)
KEYSTROKE PROGRAMMABLE with 10 programs, each can be assigned to a hotkey. That is, if you do not use IRR button (or do not know what it does), just assign your favorite program to it and call it with a single keystroke.
Сonditional jumps, loops, subroutine calls (4 level call stack)
Arbitrary text labels for output values.
Pause (0.2-1.8s) in a program.

The business part is not so useless too. Date arithmetic is useful in its own right. Percentage calculation is of general interest. So is True Value of Money -- everybody has to deal with loans nowadays.

In my opinion, it is "calculator done right", finally. The only thing I think is a mistake on their part is shifted STO key.

There's also the WP-34S project, which starts with a 30b, and reflashes it with open source firmware to a scientific. (Unfortunately, I think they got the UI very wrong.)

http://commerce.hpcalc.org/34s.php (note that you can get the stuff to do it yourself from there, you don't have to buy the whole calc from them, although some soldering required, or a somewhat hard-to-get cable, to flash it).

The 35S (or the very closely related 33S) is generally considered to not at all be one of the great ones. The 42S (or even the lower-end 32SII or even 32S) would be considered far better, but they go for stupid money (because nothing exactly like it is still being made).

If you want an HP calc with connectivity to a PC... the only 4-level RPN machine to actually do it both ways is the 41 series, and then only with optional hardware (a couple ways to do it - HP-IL (using the 82160A interface) is the most powerful way, with direct bidirectional communication using the 82973A ISA card, the 82164A serial interface, or the third-party PIL-Box USB interface. A barcode scanner (82153A) is also available (so you can print programs from your PC), and with either the dedicated HP-41 printer (82143A) and scanning, or using the IR printer module (82242A) with a PC running an IR printer emulator, you can get program dumps into the PC.

Everything else either has no communication that's compatible with a PC at all (65 and 67 can use magnetic cards, but there's no way to do anything with those except on a 65, 67, or 41 (and if you write them on a 41, they're no longer compatible with a 65 or 67 until you overwrite them again), or output only (the 42S, with IR output - which can also be added to the WP-34S).

Now, the situation is better if an RPL machine is what you want. Except for the 28 series, all of these have some form of PC I/O. The 48 series (which does not include the 48gII) and the 49G have RS-232-level serial, the 49g+ and early 48gII have USB, the 50g and late 48gII have USB and TTL-level serial (although a weird implementation), all of them (except maybe the 49G?) have bidirectional IR, and the 49g+ and 50g have SD.

What's wrong with wp-34s ui? (just curious)

The main problem I find is that so much is buried in a menu, and you can't XEQ internal functions like on real HP firmware.

For the money I think the 35s is a great daily driver. It is far from a perfect calculator (som missing functions, som glitches and small irritating misses), but it is the perfect daily driver to always have laying around in the bag or briefcase.

For the best RPN machine you can have get a DM42:
https://www.swissmicros.com/dm42.php