Tag: calculator

Sharp OZ-7000 Wizard

The Sharp OZ-7000, Amongst one of the first electronic organisers and precursor the PDA. Needs repair. Or does it?

What the listing stated:

Not working. I have replaced the two batteries and cannot get it to work. I have not touched the memory battery. See picture for actual item. Case is a bit sticky unfortunately with age.

EBay

First of all, what is it?

The Sharp OZ-7000 Electronic organiser / Calculator

The Sharp Wizard series, introduced by the Sharp Corporation in 1989, was among the first electronic organizers and a precursor to personal digital assistants (PDAs). The debut model, the OZ-7000 (known as the IQ-7000 in Europe), combined organizer functions with an IC Card expansion system, allowing users to install software and memory cards. Over time, Sharp refined the series with larger displays, increased memory, and enhanced features, such as infrared communications port for wireless data transfer, touch-sensitive displays, and clamshell designs.

The out-of-the-box functionality of the OZ-7000/IQ-7000 included a memo pad, a telephone pad, calendar and scheduling with alarms and repeating events, multi-time zone clocks, and a calculator, thus covering all the basic functions found in PDAs since. The keyboard was not QWERTY, although later models, starting with OZ/IQ-8000, changed the orientation of the screen and keyboard layout.

The OZ-7000 was about 6.3 inches (163 mm) tall, 3.7 inches (94 mm) wide closed, 7.25 inches (184 mm) open, and 0.85 inches (21.5 mm) thick closed, making it much larger than later PDAs. It featured a serial port (proprietary connector) to attach to a Windows PC or Macintosh or another OZ-7xxx/OZ-8xxx device, an optional thermal printer port and a cassette tape backup. The OZ-7000/IQ-7000 model featured 32 kilobytes of internal memory and a 96 x 64 dot (8 lines x 16 characters or 4 lines x 12 characters) black and white LCD with controllable contrast but without a back light. A major advertised feature of the model was the IC Cards expansion slot for accessory cards developed by Sharp.

Wikipedia

A bit of a break from the mountain of photographic equipment I have been dealing with lately, I thought I’d take a bit of a detour and have a look at some prehistoric PDA gear, as I have also done in the past, as you will no doubt be aware of, if you have ever read any of my posts on Psion organisers.

From what I can gather, this one is a little beaten up and battle scarred, and quite simply does not work. I’ve paid the princely sum of £8:54GBP after i managed to knock the seller down by a few pounds. I just now have to await its arrival before we can carry out a thorough assessment.

Assessment:

Its here, everything is as it should be apart from the base being a bit loose in one corner where the clip inside has broken, however that’s not an issue and can probably be repaired.

The broken clip

The exterior is a little sticky but again, this is just one of those 1989 rubber enhanced products where the vulcanised rubber coating has started to degrade. A post I previously published shows how I deal with these 80’s degrading rubber issues: Sticky, Rubber camera grips

Front case
Rear case
Both sides of the case are sticky and require cleaning

The unit has three batteries, under the rear shell. These are two CR2032 and one C1616 coin cell, with the C1616 being the units memory battery. These batteries will need to be tested as this unit does not start up, the whole unit is dead. The previous owner has stated that they have changed the two main batteries but not the memory battery, testing them will tell.

The three batteries

Beyond that, all catches, buttons and switches seem to be performing as expected, no cracks or major damage to the external shell, or screen area. Naturally there are signs of usage as you would expect on an item that is now 36 years old, light signs of age related wear and tear, nothing of concern that is detrimental to its operation.

Repair:

I’m leaving the broken clip on the rear shell as it is, it’s not visibly exposing anything of the interior and to be honest needs quite a bit of force to show the gap, it’s not a problem and not necessarily requiring a repair. In normal handling it is not even noticeable, so it will remain as it is.

The main fault, and I apologise in advance, as it was not really a fault, was a misunderstanding of the unit’s operation by the previous owner. When you take the back off and change the batteries, you have to operate a switch so as to not interrupt the backup of the system.

Battery backup switch there is a “B” and a “A” setting

There are two modes and these are explained below. This switch is located inside the battery compartment and is used when replacing the main batteries to prevent data loss.

  • B stands for Backup, a setting used during the battery replacement process. The device relies on a small, separate backup battery (often a C1616 coin cell) to maintain memory while the main batteries are removed, provided the switch is in this position.
  • A stands for Active (or simply the normal operational position), which is the standard setting for everyday use once new batteries have been installed. 

To replace the main batteries safely and avoid losing your data, you must follow a specific procedure that involves setting this switch to “B”, changing the main batteries, and then switching it back to “A” after the new batteries are inserted. 

The issue here was that the batteries had been changed and the switch was put into the correct “Backup” mode. However the previous owner had not placed the switch back into the ”Active” mode when the batteries were changed and the back of the shell was put back in place. Hence the unit would not work as in theory the batteries were locked out of use. On opening the shell up, this was the first thing I looked at, and when the switch was put into the correct position the unit sprung into life once the “On” button was pushed.

When the switch was set, power applied and the unit reset to 1989

When the unit was turned on it then reset to 1989, I was able to change the times and date, and I was pleasantly surprised to find out that the date range on this unit covered the years 1901-2099. Considering this unit was released 11 years prior to the Y2K bug of 2000, it showed some advanced thinking in the implementation of these units.

Happily updated to the current date and year

One of the issues with this particular unit is that there is no backlight on the display, the display is black and white and the only change that can be made is to the contrast. Back lights eventually arrived with later models. So use of these units was pretty much limited to daylight hours, or whilst under a light source of some kind, that said the display is very good and has a good contrast range.

The unit with an example function card installed
In use in the carpark at work

The last thing I have done is clean with some IPA to remove the years of gunk and I think this was quite successful

The IPA certainly lifted some dirt

After this I have finished off with a nice polish with some car cockpit cleaner. It’s finished this repair off just nicely.

Result:

Here we have a nicely presented, clean and fully working example of a nice little bit of personal computing history.

Has come up lovely
Front fascia
Rear fascia
Looking gorgeous

So. With these older items, it’s sometimes good to just have an awareness of how these old timers operate. Get an instruction manual, study how it works, it can make the difference between selling it as damaged, when in fact there really was nothing really wrong with it. The seller could have sold this for 3 or 4 times the value that I purchased it for, but I’m not worried about that, as far as I’m concerned I got myself a bargain and to be honest, that doesn’t happen that often.

It’s a win win situation as far as I’m concerned, I win as I now have a lovely example of pre PDA technology, and it’s a small win for the environment as another piece of “Waste” has been saved from landfill.

Thanks for passing. Thanks for being there. Always appreciated 🙏

Sinclair Cambridge Memory Calculator

What the listing stated:

This auction is for a used cased Sinclair Cambridge Memory pocket calculator and original case. The item is in very good cosmetic condition as is the case which still has its instruction sheet. The item is powered with 4 x AAA batteries (not supplied) and does work although 1 of the digits is faulty and does not display (see pictures) plus the number 5 digit is not working. Please refer to the pictures and description provided before bidding.

EBay

It’s faulty…obviously

So it does work, but it doesn’t? This calculator is a model one memory calculator, that dates from around July 1973, ( Actually May 1975 see photos below) and is one of the earliest available mass produced electronic calculators available in the UK at the time. And it was produced in collaboration with a guy called (Sir) Clive Sinclair, who in the following decade would become synonymous with tech development in the UK. It retailed at £29:95GBP, and given the rate of inflation, its cost today in 2025 would be a staggering £463GBP. Wow!

Courtesy of Vintagecalculators.com

I love collecting old calculators, I couldn’t afford one back in the day when they arrived on the scene as I was only a child and probably only on about 20 pence a week pocket money, and savings and investments were not even known to me at this period of my life. The thought of saving that precious 20p a week for the next 150 weeks wouldn’t have even remotely crossed my mind. What no sweeties?

But I can buy them now, so no big issue!

So this one has become available, and I’ve been tracking it for a week or so, there were nine other people watching but I secured it for a total including postage of £14:49GBP, and I’m happy with that, it’s a piece of retro history for a very good price. Even if it remains faulty, or should I say working but not working?

This unit obviously has its problems, the button number 5 doesn’t work and one of the led digits is also not functioning. Hopefully I can get these issues sorted and soon have the calculator back up and working as it should. That would be nice. I’m looking forward to this little project.

Assessment:

It’s arrived and it’s a lot smaller than I anticipated. It has a separate hard protective case, which is a nice touch and a small info sheet on its operation. Cosmetically it’s in a good condition with just minor signs that are age related. There are no gouges or scars so it has been treated well, though it’s not pristine.

Two buttons unresponsive and one LED

Batteries go in ok but, I believe old style AAA batteries were a little wider than those used today and would sit a bit more snuggly in the battery compartment. As you can see there is a little wriggle room here, and springs at both ends need adjusting to help prevent this. I may have to use some spacers so the batteries sit tighter in place.

Gaps between batteries – means movement

The switch is a bit temperamental and can be seen quite plainly from the battery compartment. It looks strangely out of place with no batteries in place.

Switch off
Switch on

It is such a basic design solely relying on tension of a small metal plate to short across the connection points. Should be a simple enough issue to sort.

There is a little battery contamination on one of the battery contacts, again this shouldn’t be too much of an issue and should clean up ok with some IPA.

Some battery contamination

It was originally reported that there was one unresponsive button this being the number “5”, there is also another unresponsive button, the multiplication “X” button. There is also one LED indicator, the 4th one in from the left hand side that is not operating. Add to this the issue with the On/Off switch and the contamination, and the original faults reported in the original sales pitch have now doubled. I just wish people would spend more time going over the issues and then give actual accurate feedback as to what the real faults are, it would make for a far more pleasant buying experience. Rant over.

There doesn’t seem to be a single screw holding the body together, I just hope it isn’t all heat welded.

Let’s try to get inside.

Repair:

Well it cracked open quite nicely with no issues with just a plastic flat prise tool. The main board just sat comfortably in the unit, secure, and not a screw in sight. Strange as time moves on some of the games units I come across have best part of fifty of the little blighters to remove before you get anywhere. sometimes the old way is good.

Bare board
Opposite side of board
Date is May 1975

The dismantling of the keyboard is a little complex and you have to take time and make sure you know how it’s going to go back together, it’s just a bit fiddly. The board is quite straightforward and as soon as I see some of the IC’s it dates the unit perfectly. The chips are dated May 1975, and that is about 18 months younger than what I originally thought, it’s quite informative to get inside and learn occasionally and this is just as good as having a birth certificate presented to you. All good stuff.

I’ve proved that there isn’t a problem with the missing digit on the display as using my multimeter in diode mode I am able to prove that this LED is working fine.

LED working

The picture shows just one part of the display range on this particular digit, I can assure you all other sections of the display are also working.

Regarding the case with the buttons not working. I have checked this out for continuity and both digits go through the same portion of the main IC and there doesn’t appear to be any broken traces. It’s a strange one but I have also found some really poor solder joints that are either cold joints or just poorly soldered from the start, there are a couple of resistors that need re soldering. It may be nothing at all, but it needs attention, a full reflow wouldn’t go amiss or take too much time.

Faulty resistor joint

I’ve reflowed the entire board due to there being a few cold solder joints.

Full reflow completed

On top of this I have taken off two old capacitors and tested them out of circuit, and both were out of their operable range of +/- 10%. As a result of this I have replaced the offending components with comparable new ones.

Old capacitors
New capacitors

Even with all these extra tasks being undertaken there is absolutely no change in the way it operates. Nothing has gotten worse, the faults that were originally there still remain. I have done some research on line and carried out some further tests and checked expected voltages, most are within range except one that appears to be less than its expected value. After testing everything on this board, every component I can only surmise that one of the three chips has failed, I suspect very much that this, the main chip, a CZL550 integrated circuit. Otherwise known as “Calculator on a chip” is the one that is at fault.

A CZL550 chip

To be quite honest these chips are fairly rare and command a price far in excess of what I paid for the original unit, and I don’t really want to do that. I think I’ll wait around to see if I can secure another faulty unit to complete this repair, so in the meantime, and until I can secure such a unit I will put this repair on hold.

Result:

Well, it’s not what I wanted but sometimes you just can’t win with some of these old projects. In no way am I walking away from it, it’s just that the parts are so difficult to get hold of that you really do have to just wait until a sufficiently faulty one comes up for sale. And that could be days, it could be weeks or months. So for now i admit defeat, but it will not be going to trash. It will remain in my ever expanding “To do” box, for me to pick up on at a later date. And when I am in a position to move this project on, I’ll pick it up in a continuation of this post.

Many thanks for passing by. It’s always appreciated.

Exec Helper 8200 electronic organiser

What the listing stated:

Good condition – with instructions and original box

EBay

No beating about the bush, straight to the point. No messing. Cost me the grand total including postage of £9.94Gbp

What? You’ve never heard of it? Have a google and I think you will agree there is very little information anywhere regarding this unit. There may be a few items on eBay, where you will see a couple on sale (normally faulty) for a very reasonable price, however all are missing two very important items, a box and instructions, the latter being as rare as hens teeth.

Exec Helper 8200 electronic organiser

I’m fortunate to have an excellent example now, with both with only one polystyrene insert and not two, a box and instructions. They call it an organiser, that really is an overstatement, because if you read below you will see it is a really difficult unit to get to grips with. However it can be done, it just takes patience. The unit has three functions that are: Dictionary, Address book and Calculator.

This isn’t a repair video. As there is not a thing wrong with it, it’s absolutely cosmetically perfect. It just requires you to read thoroughly through the instructions, if you are fortunate enough to have some that is, and in this instance I can be very smug. I do have those original instructions, and there are probably more copies of the Magna Carta out there than there are instructions for this unit, or so it seems.

This video was from a chap, who posted it on YouTube a couple of years back. In the video the presenter had no instructions to follow. He also knew nothing at all about this unit. Its origin, age and use was a mystery. Using the Exec Helper 8200 can be both perplexing and frustrating.

Exec Helper 8200

What it does

  • Dictionary

One of the main features of this unit is its dictionary function. Users can Type in a word and press enter to retrieve its confirmation as a valid word. However, the device does not provide definitions or additional information beyond confirming the existence of the entered word. While it does allow scrolling through words, the lack of comprehensive definitions limits its utility as a traditional dictionary. Additionally, any misspelled words will not be recognized, resulting in a “not in memory” message.

  • Address book

The address book feature of the unit offers the potential to store and search for contact information. However, the functionality of this feature is somewhat confusing and not user-friendly. Users are prompted to enter a name, but pressing enter does not submit the entry. Instead, a separate search button needs to be pressed. The device’s scrolling and next line buttons suggest the ability to store multiple addresses, but the precise method of doing so remains unclear. Overall, the address book feature of the unit lacks intuitive design and may frustrate users attempting to utilise it effectively.

  • Calculator

In addition to its dictionary and address book capabilities, the unit functions as a calculator. When numbers are entered, the device immediately switches to calculator mode, allowing for basic mathematical operations. The calculator feature includes memory recall, addition, subtraction, percentages, and other commonly used functions. Unlike the address book and dictionary functions, the calculator feature of the unit appear to be straightforward and functional.

Date of manufacture?

The exact release date and availability of this unit remains uncertain. Judging from its design and styling, it is likely that the device originated from the late 80s or early 90s. However, due to its scarcity, finding a working unit or acquiring one in boxed condition can be challenging. I struck lucky with this one.

That said it probably was once a mass produced piece of tat that failed so miserably, that everyone who owned one threw them away, before they could ever be associated with owning one. They were that bad….or were they? I don’t know, there is so little out there about them that you can’t really make a reasonable judgement or gain constructive feedback regarding them.

It was probably a unit that was killed off in its infancy by one of the bigger names that were starting out around the mid 80’s that had a better, product and presence at this particular time. (Psion for example) A simple case of being in the right place at the right time.

Or is that the right place at the wrong time?

Edit: I have done some digging around and it seems to be that these units were sold via the UK newspaper “The Daily Mail” as a reader offer. I even have the original return form for it however there is no sign of a date. The only thing that ties it to the 90s is that refunds can go either to “Access or Visa. The Access “ Your flexible friend” card ceased in 1991 when the banks involved started doing their own card transactions. So it was definitely very early 90s maybe even late 80s. I’ll update this post if I uncover anything further.