5-Level RPN Calc from the early days

[Matt Agajanian]

Hello all.

I am trying to recall the 5-level RPN calc that was the topic of a thread not too far back in the original Forum days.

If anyone recallls which calc this was, please refresh my memory.

Thanks.

[Manolo Sobrino]

Try here.

[Matt Agajanian]

Thanks. I'll see what pops up (pun intended).

YUP, it worked. Pretty neat webpage too.

I found the mystery calc when I hit on the old MoHPC thread, "Is RPN a pattern of HP?"

The Heathkit OC-1401 was mentioned in that thread and that's the calc I was thinking of.

Thanks.

[Garth Wilson]

(04-05-2014 03:48 AM)Manolo Sobrino Wrote:  Try here.

or ixquick.com which works the same but without the polical and privacy issues of Google. I will not use Google.
ixquick.com, search term site:www.hpmuseum.org "5-level stack"

[Mark Hardman]

(04-05-2014 03:55 AM)Matt Agajanian Wrote:  The Heathkit OC-1401 was mentioned in that thread and that's the calc I was thinking of.

As usual, Katie even has a copy of the calculator's manual:

Heathkit Manual for the Aircraft Navigation Computer Model OC-1401

I want one!

Mark Hardman

[Maximilian Hohmann]

(04-05-2014 02:07 PM)Mark Hardman Wrote:  I want one!

Oh yes! It took me several years to find a good one at an affordable price, but now it's mine :-) Great calculator, but unfortunately not required any longer for it's original purpose. Look at the classifieds of this forum, there was one on offer some time ago, maybe it is still available.

[walter b]

Does it feature a reasonable keyboard? Tactile feedback?

d:-?

[Katie Wasserman]

(04-05-2014 05:14 PM)walter b Wrote:  Does it feature a reasonable keyboard? Tactile feedback?

Yes! It got a nice solid feel, takes a good amount of force and make a pretty loud sound -- a bit hollow sounding because of the fairly large plastic case it's in.
I don't like the keyboard layout at all though, but then again being an RPN calculator was not it's primary mission.

This was such an innovative calculator: 5-level RPN, 3 microcontrollers, many power supply options, choice of semi-permanent keyboard overlays, not to mention all the navigation, fuel and timer functions. And, of course if was available per-assembled or as a kit.

[Maximilian Hohmann]

(04-05-2014 05:14 PM)walter b Wrote:  Does it feature a reasonable keyboard? Tactile feedback?

It's OK. Not as good as HP, not as bad as Ti. But for such a niche product, the quality is really good. Most later aviation calculators have rubber keys