Monday, May 09, 2011

Answer to Old Gadgets Quiz #1

The gadget featured in Old Gadgets Quiz #1 is the Casio ST1 digital stopwatch cum calculator. The button on the right is the start/stop button and the vertical sliding switch is the mode selector. In calculator mode, you can open the plaster door to access the buttons.

I bought this device primarily for its digital stopwatch function. The year was around 1980 or 81 and I was working as an industrial engineer in Philips Singapore. As IEs, my colleagues and I had to do a lot of time studies in the factory shopfloor. Prior to the arrival of the ST1, we used analogue stopwatches which were really very difficult to use, especially when you were timing short cycle time operations.

In time studies, we often used a technique called Flyback Timing. You first observed an operation and divided it into a series of work elements. Then you would stand next to the production operator and time each of these elements as she worked; using a special stopwatch whereby the hand would actually ‘flyback’ to zero every time you pressed the button, and commence timing the next element immediately. You then had to record the reading and start observing the next element. It required a lot of skill, especially if the work elements are very short – say a few seconds in duration. It is made worse when you had to do what is called Rating; i.e. assessed the working speed of the operation and assign a numerical Rating to it. Strictly speaking you are supposed rate every single element, but often we took the short cut and did one common rating for the entire cycle, especially when we could see that the operator’s working pace was quite steady/consistent.

Those who have not worked in factory before will probably find my explanation difficult to follow. Anyway, let’s just say that it was extremely demanding, and you had to be very alert because if you missed a reading you cannot ask the operator to stop for you. Furthermore, our results were used in very sensitive applications like setting production targets and cost prices. Hence we IEs were not very popular with the girls on the shopfloor. Some of them called us ‘sat yan wong’ (杀人王) which is Cantonese for ‘notorious killers’; because our standards were too tight and the girls had a tough time meeting the targets.

However, with the digital stopwatch, things became much simpler. When the stopwatch is set to LAP-2 mode, every time you pressed the stop/start button, the reading is frozen and you could ‘take your own sweet time’ so to speak to record the reading. Meantime, the clock is reset to zero and starts timing the next cycle/element. Furthermore, it is much easier to remember a numerical reading when it is displayed in digital mode than in analogue mode.

One day my colleague Roger Lee came to office with this Casio ST-1 which he found at a shop in People’s Park Complex paying about $70+ for it. The rest of us in the IE dept were very excited and rushed down after work to buy one for ourselves. The shopkeeper did not know how desperately we wanted this device and was quite happy to sell it to us for about $60+. Apparently there was very low demand for such a specialized device and he was quite happy to make the sale.

A modern stopwatch with dual displays.

PS – I found someone trying to sell the ST-1 on eBay for about £11. That’s even lower than the original price that we paid. No way will I part with my ST-1 at that price.


veii said...

Any electronic device with an LCD that old and still functional is a diamond.

Tom said...

I have neverseen a Digital stopwatch cum Calculator, I wonder if anyone has ever seen this old calculatorI have,it was made in Sweden about 1935-1945, the name of this old calculator is called ,Aktiebolaget Original Odhner Coteborg Lusid, Pinwheel Calculator with 10 - digit setting register 13-digit Accumulator register 8-digit Revolutions register.The waight of the calculator is 5Kg.(11 pounds )

Lam Chun See said...

That's very interesting Tom.How about sending me some photos and description to share with readers of this blog.

Lam Chun See said...

Forgot to mention that the display is LED type. Don't think they make such displays anymore; do they?

I am going to keep it in a dry box and leave it to my grand children; assuming of course ..... Haha.

Unknown said...

It looks like a vacuum tube fluorescent display that pre-dates LED and LCD.I used to build digital alarm clocks using a similar type of display. Had to be careful with soldering the leads. Too much heat would destry the display.