What the heck, it is a calculator and I just restored it....


The pen comes of course complete and together, stating the obvious here! It brings up a good point, how is it assembled; glue, screws, clamps, clips, pressure fit.....

Not knowing the answers and not finding any info I went with the glued and screwed scenario. At first I thought the Pen control nib was pressed and glued in position so I gently started prying it out. BIG mistake, it is actually held in place by two tiny screws. I managed to destroy the threaded plastic hole on one before realizing my mistake. This however led to the revelation that the top keyboard shell must have been applied after as it covers the screws.

I heated the top shell gently and found that an exacto knife would slide in between the top shell and the main pen body. Carefully I worked the knife along the whole seam connection the two parts. I also applied a little laqueur thinner with a fine brush which help separate the glue. Use it sparingly as you don't want it on the plastic parts. Just apply the laquer along the seam only!

Once the top shell was removed I applied some paint remover using a small artist brush on the inside lip of the top shell and removed all the excess glue. Once the glue was removed I placed the top shell on an extremely flat surface on a piece of paper. I then, using a rounded spoon handle edge, rubbed the inside lid applying pressure to smooth out the occasional ding the exacto knife made while loosening the top shell from the main body.

This photo shows the top shell removed and can be used as a disassembly or assembly reference:

The offending screws which are completely invisible with the top shell in place:

Follow the directions for sliding in or out of the main pen shell as you could damage the connections between the LED section and main keyboard:

The module:

The solder joints:

Testing; "Its' alive"

Closeup of the display now fixed:

Cut some foam inserts to replace the original of which most had turned to dust:

Dry assembled to make sure all parts fit, as a prelude to gluing. Now to gluing, what to use, crazy glue for metal, epoxy, contact cement etc

I am not partial to the contact cement as it is to thick when cured and the seam would be visible. Epoxy seems the way to go at the moment but I would like a liquid glue that can seep into the seam as opposed to applying the glue with a brush like epoxy. Also have to figure away two pressure the to shells together, probably tape of some kind.

Any ideas on the glue let me know.

Cheers, Geoff


That's a lovely thing ! Do you know who made it ?



It was made by Tru-phonic Sound, Inc..


Thanks for that strip down report on one of my favorite calculators, I wondered how they put that together. I have a large collection of calculators on display and ready to play with -- including pretty much all of the HP's. When visitors look over my collection invariably it's the Calc-U-Pen that they are most interested in.


Edited: 12 Feb 2008, 12:42 p.m. after one or more responses were posted



This is a link that gives some more detail on this interesting gadget. From the link:

"The actual manufacturer is not known and is not present on any of the currently-known printed materials for the calculator (such as sales ads and operating manual). The back cover of the operating manual has a guarantee with returns to be sent to Tru-phonic Sound company of Bellwood, Illinois (USA), but that may have just been one US distributor or servicing agent. An LCD version of a Calcu-pen (with the same spelling) was made in 1981 by Satolex, an Asian company".





I stand corrected, Satolex does seem to be the manufacturer. Take a look at this ebay auction for a calculighter

They seemed to like making high-quality hybrids of calculators and other objects that people carry around with them.


Edited: 12 Feb 2008, 1:08 p.m.


Hey thats nice!

Then the smoker can calculate ETTL (estimated time to live)...

Best regards
(Non smoker)


Beautiful job! Thank you for photographing it and explaining it so well. (And congrats on your success in fixing it!) Guy

Possibly Related Threads…
Thread Author Replies Views Last Post
  Egyptian Fractions on the WP-34s. Just for the heck of it. Marcel Samek 13 3,490 04-03-2013, 05:31 PM
Last Post: Paul Dale
  HP-65 "restored?" with extras on ebay Dan Lewis 10 2,586 11-29-2012, 12:36 AM
Last Post: Dan Lewis
  Heck Yeah! Mars! Tim Wessman 45 10,029 08-08-2012, 10:00 PM
Last Post: Luiz C. Vieira (Brazil)
  Now where the heck did this calc come from?...a hint, perhaps? Dallas Osborne 5 1,657 02-04-2008, 09:13 PM
Last Post: Dallas Osborne
  What the heck is this? David Ramsey 7 1,976 03-01-2004, 08:04 AM
Last Post: Valentin Albillo

Forum Jump: