Sinclair LED watch module

[SASM]

Hello to all,

is there demand for a Sinclair LED watch module replacement? If yes, can somebody describe how the watch works?

Thanks, Hanno.

[bucko170]

The Blackwatch is still regarded as an iconic piece here in the UK and I imagine the watch will also attract the attention of collectors of Sir Clive Sinclair's other products (C5, calculators, computers etc) the failure rate for the watch was very high so whilst the watch did not sell in the same numbers as other watches of the era I would of thought it would be a worthy addition to the SASM range.

The blackwatch was also produced in a grey and a very rare white version and to my knowledge two different modules were produced one with and one without the date feature, I have the non-date version which I assume was the earlier version - let me know what you need, I don't wear my on a daily basis so if you want to have a closer look at it I can post it to you.

[Ade51]

I think that it would be a great idea for a SASM for the Sinclair. I for one would love to have a reliable and working example.

[Old Tom]

I think the biggest problem with producing a replacement module for a Sinclair will arise in trying to duplicate the cheap & nasty mechanical assembly methods used in the watch- the front and rear contacts for the setting/display buttons were etched onto a self adhesive wrap around flexible strip and getting this off intact is usually the biggest challenge in repairing a Black Watch. The actual electronic components were quite reliable- the circuit board was not, made from the cheapest Copper covered board imaginable and with no protective plating on the traces the glue from the wrap around strip would mix with a little water and dissolve the Copper off the board in no time especially when the watch was under power.

The modules were also in a state of continuous "development" and layout/discrete components vary a lot- the later time & date module didn't vary much (I've only seen two variations) compared to at least five generations of the first H:M, M:S module.

I suppose if you ditch the rear set button and have setting and display on the front buttons then the module would be easier to duplicate (I'm thinking H:M on left button, M:S or S:D on right button, press both together to enter setting mode).

[SASM]

Thanks for the feedback. I do have a sample watch from Jürgen Hofstaedter in my hands. I could use micro smd pushbuttons to solve the bad switch layout. However I think as OldTom just mentioned the worst part was the circuit board itself, so that the pushbuttons should work much better with a newer one. I will start with the layout during the weekend. I am sure I will have a few questions regarding the software which I will post right here.

Does anybody know how many watches were produced with DIL - Display?

Thanks for your help.

By the way, I do not own a Sinclair watch myself, but another well-known Sinclair species: The ZX Spectrum :)

[Old Tom]

Typical backside yuk;-



And about a third generation 1st type front view (missing crystal and a small ceramic capacitor upper right);-



As far as I know all the original BWs had the five digit Hewlett Packard displays in them