Advice on Purchasing an HP

[burgarwulf]

(09-20-2018 09:36 PM)burkhard Wrote:  I think your experience on the 28S was somewhat unusual, although keep in mind it 30 years old or close to it, so anything is possible. More likely those 28C/S (like all the clamshells excepting a late production 19BII) might have broken / cracked battery door issues. Many of those sold on eBay already have that problem and even if you get a good one, you need to be careful with that, as it is a fragile point on that calculator. Still the 28S is a nice machine and not super crazy expensive. I have a nearly perfect one which is a joy to use.

Almost every series has *some* weak point, but treated reasonably well, you can buy one that has lasted for decades and will keep doing so. Some of the problems can be repaired easily, some less so.

Still, I'd
1) Figure out what model does what you want and then
2) Learn its weak points (ask here) and things to look for buying one used.

Was the 28S otherwise your "dream machine"? If so, I'd get another (ask for pictures of the battery door and surrounding area on the calculator itself).

I wouldn't necessarily say dream machine, but I do find the dual keyboard appealing for whatever reason. I'm a big fan of HP test gear as well and I was wanting a real calculator (phones work...but it just has an unnatural feel to me, plus the screen cutting out) for general work purposes.

I'm glad to hear that was likely a more rare situation, I have been doing some repair work on other gear and so was hoping the 28S would be approachable. Think it was the first google result that killed that dream off.

It had already been partially opened so I finished the deed as it were as carefully as I could. She still works, but that row will not respond regardless of my attempts. I haven't had the time to get any further in to it than some simple tests of the key pad itself. I will say it has one of the nicer looking PCBs I've ever had the luck of seeing.

(09-20-2018 10:01 PM)smp Wrote:  Depending on how much you are willing to spend, this may be of interest:

https://www.ebay.com/itm/Vintage-HP-28S-...SwW55bb6Hs

Good looking calculator with manuals.

Good luck!

smp

Had actually been eyeing that one since I discovered the last one had been refunded.

(09-20-2018 10:43 PM)John Cadick Wrote:  As another option you might consider posting your "want" on the "Classifieds" forum here on the Museum. The Auction Site (TAS - that's what we call ebay here) is always a bit of a gamble. Primarily I think because many (if not most)of the sellers on TAS are not especially knowledgeable about calculators.

Pretty much everyone on this forum knows calculators, especially HP, and if they have one to sell they will tell you accurately about its condition.

John

I stumbled into that section after posting this, and I'll definitely have to keep that in mind.

(09-21-2018 12:00 AM)RMollov Wrote:  IMO your best bet is the DM-42S, not exactly HP from the golden era, but with the exception of the keyboard, everything else is excellent and far superior to HP's.
All good HP calcs are nowdays old enough and not being "serviceable" isn't make them good buy.

(09-21-2018 12:23 AM)John Keith Wrote:  Though it is a different form factor, you may want to consider an HP48GX. They are not too expensive and much more capable than the 28S, especially since the 48 has 2-way serial communication which the 28 lacks.

There are literally thousands of programs available for the 48 series from hpcalc.org and other sites.

(09-21-2018 02:42 AM)Craig Bladow Wrote:  The HP-35S can be currently purchased new, online (albeit not from hp.com - out of stock) for ~~$50.

(09-21-2018 03:01 AM)KF6GPE Wrote:  I'd echo the suggestion of an HP48 if you can get one. I have both a 28 and a 48. The hinge on the 28 is an amazing bit of engineering, but is also another failure point. My 48 has worked flawlessly since I picked it up halfway through my university days.

And yeah, if you want new- and RPN, the Swiss Micros DM42 can't be beat. The DM41 is a lot of fun, too, and slightly smaller (also RPN). One nice thing about the various Swiss Micros machines is you can easily get stuff on and off of them via USB. If you get a '48, you have to mess with USB to serial and get a special cable if you want to copy anything on or off of it.

Regardless, have fun! Amazing machines.

The 48 does look like a very nice version as well. Looks considerably more solid build wise.

I'm actually really surprised HP's website has that 35S listed, I didn't even bother looking there when I started my search.

I shouldn't have looked at those Swiss Micros though. Way too tempted by those even in addition. At first I had mistaken another retailer I'm familiar with, Micro Swiss, which didn't make much sense as they're a manufacturer of 3D printer parts!

Thank you for all the information, was a bit surprised by all the responses. Taken a lot into consideration and I will post after some more thought!