Recent changes to this Calculator Museum

2024-04-14 Sad news. The CCD of my HP ScanJet 4C, the scanner graciously donated my Mikki, decided to join the choir invisible. It started with a green band at the right of all scans and now everything turned yellow (plus said green bank, now tinted yellow). Back to the HP ScanJet IIcx for now.


2024-04-12 Fixed a long standing bug (introduced on 2023-01-09, see below) where a calculator when shown full-window or full-screen isn't dismissed when pushing the back of forward buttons of a browser or when swiping back and forth when using it on mobile.


2024-01-13 Checked and updated links to other websites.


2024-01-08 Implemented a method to make the browser's back- and forward buttons functional even though part of this site runs in an IFRAME. This is done by means of the History API (link valid 2024-01-13). Seems to work quite good actually.


2024-01-07 No cookies required fortunately, I invented a different technique. Now, when a specific calculator page is loaded, e.g. by refreshing the page or by linking to it using the "?" search tag trick the left column automatically scrolls to that calculator by internally using Text Fragments (link valid 2024-01-13).

A (quite annoying) side-effect of the way my site is implemented (using an IFRAME) is that the browsers' back and forward buttons do not work as expected. Not sure yet on how to work around that issue. Maybe this can be solved using the HTML5 features history.replaceState and history.pushState. Work in progress.


2024-01-06 More changes. Since my site uses only HTML and JAVASCRIPT, no database and no PHP I had to think of a way to make direct URL's possible. They were already possible by linking directly to a calculator’ -body page or -index page, now it’s also possible to directly link to a calculator with all of the rest of the site visible. I now misuse the "?" search tag to accomplish that. So, for instance, https://calculator-museum.nl/?casio-fx602p will now directly link to the CASIO FX-602P page on the museum. It is still possible to directly link to only the stand-alone page of the calculator as it was previously, as in this case, use https://calculator-museum.nl/calculators/casio-fx602p-index.html. All calculators should have their own stand-alone page imho. A nice side-effect is that refreshing a page won't also jump to the list of recently added stuff. Now I will have to find a solution to keeping the scroll position of the left column on refresh, that might involve cookies which I would like to avoid.


2024-01-01 Started to play around a bit with making the site easier to navigate. Quick links to different sets of calculators by type in the NAVIGATION section that also jump right to the OVERVIEW page of that type. Plus clicking at the top of the left and right columns will scroll to the top of that column, as expected, especially on mobile devices. Thanks, Jan Horlings, for pointing this out. Makes the site much more usable. Also increased the font size on mobile devices and made some of the longer words in the left column hyphenable (if that's a word).


2023-11-07 Finally gave some much needed and long overdue love to the page of my beloved CASIO FX-602P. More about the calculator itself and some nice tips and tricks, including a way to retrieve passwords.


20230520 Setup 2023-08-06 A bit of a pause. Mainly because it is summertime and I’d rather be outdoor than behind my computer, but also because of yet another issue. The videocard of the modern computer I use to process the scans had shorted out. It was a AMD Radeon RX 6800 card, probably from a batch that was incorrectly stored in a too moist warehouse in Germany. Replaced now by an AMD Radeon RX 6900 XT. Today I welcome the sinclair Scientific Programmable to my museum. Thanks, Richard Pilkington! Also this is my new setup using the HP ScanJet 4C.


2023-05-05 As of now I have a working setup again. I combined hardware parts of two of my PowerMac G4’s to produce one PowerMac G4 with working Ethernet, SCSI and a working fan. A couple of weeks ago, a dear friend of mine (hello Mikki!) cleared out his stuff and he had a HP ScanJet 4C lying about, wondering if he should bring it to recycling. I happily adopted it, to have another backup scanner. Mikki had been taking very good care of his scanner, it looks almost brand new. Today I decided to try it out using my new setup, not hoping for good results remembering the coloured shadow-issues with the HP ScanJet 4P (see explanation below). To my surprise the HP ScanJet 4C seems to deliver excellent scanning results! Now I’m actually wondering if I should redo all my previous scans (please tell me not to!)... Googling I found a page on the differences between the 4P and the 4C. Read it here (link valid 2024-01-13). The differences seems to explain the different scan results (was the 4P cheaper than the 4C?). There is a nice technical article on the HP ScanJet 4C by HP itself, from 1997. You can read it here (link valid 2024-01-13). There is also an hour long video on YouTube about getting a working setup using the HP ScanJet 4C. You can watch this video, by Shelby at Tech Tangents, here (link valid 2024-01-13) if you’ve got an hour to spare.

It seems I’ve now found my ideal scanning setup. A picture of the new setup will follow. Hopefully this setup will last a while. I will try to use the working PSU from the HP ScanJet 3P to fix my broken HP ScanJet 3C as an extra backup scanner in case the HP ScanJet 4C fails.


20230502 Setup 2023-05-02 As an alternative to using my ancient (and now broken) PowerMac G3 to make scans using the HP ScanJet IIcx, I tried to use VueScan on modern hardware. According to its documentation the ScanJet should be supported. I still have a couple of Orange Micro SCSI to Firewire converters and the ScanJet is actually visible under FireWire on a modern Mac using that adapter. But no joy with VueScan, it crashes when the scanner is seen. I tried various macOS versions and versions of VueScan. According to their Technical Support the conclusion was that, apparently, it does not work then.

Next step, getting an old PowerMac G4 operational. I still have three of them, none of them having SCSI and all having some issues. To add SCSI to the PowerMac G4 a SCSI card is required, and I remembered Adaptec had various Mac OS (and Mac OS X) compatible SCSI cards back then. To my surprise the Adaptec 2906 SCSI card was for sale on eBay and I bought one for a low price. It arrived today from overseas. When I put it into my PowerMac G4 I noticed that booting was problematic. Yet another problem: I/O errors on the 120 GB hard drive... Luckily I also still have spare PATA hard drives, and I was able to rescue the necessary system files and HP DeskScan II. I also needed ancient Mac OS 9 drivers for the Adaptec SCSI card but that was no problem because firstly I still had them in my own software archive and secondly they are, to my surprise, still available on Adaptec’s site (link no longer valid)!

So I can scan again. The setup is not as esthetically pleasing as it was with the PowerMac G3 but it gets the job done. Hopefully this setup will last longer.


2023-04-14 Another day, another challenge. The PowerMac G3 I used to be able to work with the HP ScanJet IIcx suddenly broke down. No more boot-chime. When I took it apart I noticed its PRAM battery had died and leaked its contents all over the motherboard. I obviously should have noticed that before but i didn’t. The next step is to try to fix it and if that does not work I will have to find an Adaptec 2906 SCSI card somewhere to use one of the newer PowerMac G4’s I kept all these years.


20230322 Setup 2023-03-21 Being in some ways a perfectionist is not always helpful. Working with my "new" ancient HP ScanJet 4P scanner, see the previous item, I noticed that all shadows on the newly scanned calculators had an ugly green colour shade. Probably because the HP ScanJet 4P is not meant to scan depth and its optical receptor has separate receptors for R, G, and B positioned in such a way as to cause coloured shadows. I stopped doing new scans when I noticed it. Then I came across an even older HP ScanJet IIcx that I could buy for € 50 from Chipmunk International (link valid 2024-04-14), a scanner from the 1990’s, and it seems to do exactly what I need it to do. It scans with quite some depth-of-field and the colours are allright as well after a mayor cleanup. The ScanJet IIcx needed thorough cleaning as it was full of dead spiders and the three mirrors of the optical part and the camera lens itself were extremely dirty. I started re-scanning the couple of calculators previously scanned with the HP ScanJet 4P.


2023-02-21 The last 18 calculators added to the musem were already scanned all the way back in 2006. They were scanned using an old HP ScanJet 3C SCSI scanner. I tried various modern scanners but none of them had the required depth-of-field to be able to properly scan calculators. The HP ScanJet 3C had depth-of-field, modern scanners focus only directly on the scan bed resulting in perfectly sharp key tops and a vaguely visible calculator. When I made a new (old, actually) set-up using an antique PowerMac G3 and my HP ScanJet 3C to make new scans, my ScanJet wouldn’t turn on. Its power supply (PSU) had died. I did some measurements on it’s PCB but couldn’t find an obvious cause. Luckily there was a HP ScanJet 4P for sale on a Dutch auction site and I bought it for € 25 (plus a 250 km roundtrip) and it works! So, finally I as able to do a brand new calculator scan, the honour to the first new scan goes to the beautiful Aristo M 76!


2023-02-05 Found a way to properly reset the zoom when the site is used as a Web App on an iPhone, and the device’s orientation is changed after zooming. Now the Web App is a really nice interface to my little museum.


2023-02-04 Changed the capitalisation of brand names throughout the museum to make it more conform the brand names’ own capitalisation.


2023-01-24 Changed the layout of quoted reader’s e-mails so that they also scale in a "responsive" way.


2023-01-22 Fixed the viewport issue on iOS. Now works well in portrait and landscape mode. You can also turn the website in a Web App on iOS, simply press the Share button and add it to your home screen. The Web App version works quite well. That is until you zoom and change your iPhone’s orientation. iOS zooms in and I still have not found a way to cancel that.


2023-01-20 Changed the way full screen calculator images are shown. Now the whole window is used. Improved mobile experience (at least on an iPhone, no other phones to test it with). Better readability. The only problem is the viewport on iOS, it is impossible to scroll to the bottom of a page.


2023-01-18 Made pictures more "responsive". They now scale down on smaller windows. The maximum size is still in relation to all other calculators. Also made the calculator descriptions more responsive, the page will switch to a one-column layout on smaller windows. Same for the calculator overview pages. Better usable on a mobile device.


2023-01-17 Moved to new URL https://calculator-museum.nl. Will provide the necessary rewrites to keep external references in the air.


2023-01-16 Decided to move away from http://ernst.mulder.com. Why? Because it is a legacy subdomain of mulder.com, not owned by me. Had a chat with Hover.com and they tell me the legacy subdomain is still online but might cease to function any moment. I put a permanent redirection on the old site and am low looking for a cool domain name for a new site. For now I have stalled it under my private domain name https://mulder-thuis.nl. I know there are external links to http://ernst.mulder.com, I will try to contact site owners linking to my pages after I have decided on a new domain name. I have also removed the (ancient) non-calculator parts of the site and will from now on solely focus on calculators. External links to http://mulder-thuis.nl still work.


2023-01-15 Created a button to copy the URL of a specific page of my Calculator Museum. The icon is normally hidden and only shows up when you hover over it on the top right of a page. Only works on https://mulder-thuis.nl because http://ernst.mulder.com has no SSL. Not sure how to solve that yet. For now the button is hidden on http://ernst.mulder.com.


2023-01-14 Added a "TO THE MUSEUM" button at the top right of externally linked pages. So a link to a specific calculator on another collector’s site now has a button to see my complete calculator collection as well.


2023-01-13 External links to "body" pages to my Calculator Museum will now automatically redirect to their "index" page. Next step will be to then include a link to this Calculator Museum itself. Work in progress. I love it.


2023-01-12 The Calculator Museum part of the site has now finally moved away from using ancient FRAMESETs and FONT styles to DIV’s, CSS, Javascript and IFRAMEs. Less work than I expected. Better scalable. Handles resizing and page zoom better. No mobile version variant yet (no idea yet how to approach that). I did keep the old 1990’s look because, well, I actually quite like it, it’s clean and neat. All external links to pages of my Calculator Museum should still work. I will handle the rest of my site later on.


2023-01-09 You can now click on a calculator to see it zoomed in. Click or press escape to return to normal view.


2023-01-07 More calculators added. Also slowly transforming away from ancient HTML code and finally started using style sheets. Still have to get rid of the ancient frameset construction though (without breaking external links to my pages).


2023-01-03 After a hiatus of, what is it, 12 years (!) I finally added a new calculator to the on-line collection!


2023-01-01 Replaced calculator pictures with double resolution versions for better viewing on Retina displays.


2023-01-01 Finally removed those terrible hyperlink underlines...


2023-01-01 Added repair info on the TI-68.


2022-12-30 Finally added information on the TRS-80 PC-2.


2022-12-30 Checked and updated links to other websites.