Switches, push buttons and lights prewired and installed in temporary front panel.

All assembly modules installed, wires will be cut to length, terminated and tidy up. I don’t have a crimping tool for 0.1″ connectors, so I have to solder all wires separately. Quite time consuming.

First power on in the enclosure. IT’S ALIVE!, working but no time set or any other fuctions.

Detail of mother board and alarm board wiring. Time set and reset functions connectors are tied together for easier recognition.

Clock is working, last thing to do is wire selectors switches for alarm.

This was rather time consuming. Measure length of wires. strip them, twist, solder, bend a hook, solder to selector, strip the other side, solder connector etc…. at lot of flux! 🙂

Alarm switch selectors are prewired and terminated with 0.1″ connectors. Input, minutes: 0-9 & 0-5, hours: 0-9 & 0-2. 4 Outputs outputs to the 74LS21N AND gate. Alarm clock set off if all 4 inputs are high.

Wiring input collectors from decade counter to one of the switches.

Detail of alarm selector wiring, please note BNC connectors for pulse input and output

Input connectors of alarm selectors are connected now cut and terminate outputs from selectors.

Terminating 0.1″ DuPont inputs from alarm switch selector. I don’t have a crimping tool, so I do it in old fashioned way and solder them.

All wires are connected, please note wires are no tidy as this is not a final form of wiring. Adjustment and cable management will be done once front panel in installed.

I have added 3″ speaker in diagonal position to the rear bottom right corner. It’s generating nice low rich tone.

Clock is working perfectly. NOS Bakelite chicken heads purchased from eBay. Please note writing on temporary front panel, made of hard board. This method is cheap and fool proof for prototyping when adjustments to design are needed.

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