Restoring LED indicators on old Russian Elektronika 1

[Andrew Babanin]

The module came rusty with lost LED indicators.



I cleaned up the board of rust and defected indicator



Then soldered contacts, put on plastic base. It is ready to glue in new indicators



All digits are glued in with silver epoxy



The right digit is wire bonded



All digits are wire bonded



Added capacitor, quartz, lens for digits

[Andrew Babanin]

A sample of restoration the module with cracked board. I found new board with installed ICs, so it was a bit easier to make the module working. It is the earliest version of ceramic serial module.

[SASM]

Amazing. Where did you find the LED dies?

[Andrew Babanin]

I've got all components to repair in small quantities. But it is easy to remove components from broken plate with spirit. It takes maybe 1 hour to remove LEDs, ICs. Most of them you can use again.

[egomon]

wow just unbelievable work you do!

[SASM]

But it is easy to remove components from broken plate with spirit. It takes maybe 1 hour to remove LEDs, ICs. Most of them you can use again.

That´s really interesting, thank you! You mean you put the old boards in denatured alcohol, wait for an hour and then these componets will come off easily?

I´ve never tought about it, but will try to produce some Hughes 27mm modules using your method. I will then epoxy them back on a new circuit, write a program for the wire bonder and bond them again. Let´s see how that turns out. A pity that you are so far away.

[Andrew Babanin]

Yes sure. ICs and LEDs mostly easily removed. LEDS glued in with silver epoxy, ICs mostly glued in with ordinary epoxy. Mostly I use NOS ICs and LEDs, but in some sort of projects with restoration use old ones.

[Andrew Babanin]

viewtopic.php?f=82&t=8987 - here also a sample of restoration with removing old components with alcohol.

[Andrew Babanin]

The first commercial project with bonding - re bonded 90% of wires

[SASM]

you manage that without heating from below? I mean there are ICs on the back side of the module. It´s already hard to put the Bulova module flat on the table. I have a huge amount of display dies and usually 0 time to write a program for the bonder. Working like you means that it´s also possible to produce watch calculator modules again. That would be incredible! Glad to have you on-board!

Hanno.

[Andrew Babanin]

In Bulova the substrate is ceramic. It fixed in plastic carrier for batteries with plastic clips. I removed ceramic part and board with contacts and quartz from the carrier (they are connected with flexible
flex cable together). From the bottom side of ceramic plate the main IC and IC for segments with no coverage at all!. At the face side - digits, covered with plastic transparent hood. It was tricky to unclip the substrate, but I've managed.
No need to heat - I fixed only ceramic part to the table of wire bonder, cable and battery board are still intact. had to bond from 3 sides. I prefer to bond plate first and IC - by second step, here had to bond in both directions.
If you find NOS chips or not damaged chips then it is real chance to make repair. I do not have enough time for restoring electronic watches because of restoration old pocket watches of 18-19 centuries and repairing modern mechanical watches with complications, but it is really interesting.
PS I use manual wire bonder, so no need programs, not good for big quantities, but from the other side with good training it is quite quickly. There was theme on WUS they wanted replica of Elektronica 1 Led watch with real LED dies of that time but with new IC and lithium battery. I've got a few thousands of 7 and 9 segment dies made in USSR for this project. Maybe it will be lucky :)
PS2 And I've checked your module once - great job, very good quality and looks very common to old original one inspite of new components.