I have used three voltmeters and mounted them on a wooden plinth with a clear Perspex cover to give the clock an industrial look.

I have modified Alan's code to run on PICBasic Pro version 3. I have also added the following.

Switched display On and Off (keeping battery backup as per Alan's design) but also allows me to turn meters Off in full power mode.

Synchronization to my Master Clock every 30 seconds

Synchronized LED & Re-Synch LED

Synchronization On & Off

Transistor meter drivers

The standard clock due to limits of the 20Mhz quartz crystal (you can't get a precise 1 sec pulse) runs fast by several seconds per day. In order to keep correct time the clock is connected to my Master Clock or LCD Master Clock and is kept in sync by 30 second pulses from the Master Clock ( the Master Clock is synchronized to the DCF77 transmitter).

The Clock also has an electronic chime via an ISD1730 audio record and playback kit from Sure Electronics. This was used to record my Long case clock chime then play it back on pulses from the master clock.

The chimes are also controlled via the Master Clock. The clock has battery backup on mains fail and can also be manually switch to backup mode (display off switch) if required.

Hacking the voltmeter scales

The meters have had their original scales removed and are then rubbed down to bare metal before being re-sprayed in off white to make them look old.

The new scales were drawn up in TurboCad and then printed on inkjet transfer paper before being cut out and applied to the blank scales. I used the same paper to make the labels for the switches.

Clock Controls & indicators

Chime LED- lights while clock is chiming

Sync Pulse LED- lights when sync pulse received from master

Re-Sync LED- lights when Sync Pulse corrects clock

Seconds Led-Indicates Seconds

Hour/Meter Select- Sets hours and when Scale Adjust is On selects which meter scale to adjust

Minutes/Scale Increase- Sets Minutes and when Scale Adjust is On increases scale deflection

Seconds/Scale Decrease- Resets Seconds and when Scale Adjust is On decreases scale deflection

Scale Adjust-When On enables meter scale adjustment

Chime-Turns Hour Chime On & Off

Smooth Sec- When On Seconds meter deflect smoothly with each second, when off each seconds moves the meter in 1 second increments

Sync-Turns the Master Clock sync On & Off

Display-Turns the meter displays On or Off correct synchronised time is also maintained.

Chime Record Jack-Audio input to Sure Electronics Digital record and playback board for recording hour Chime


I purchased the main board and components of this clock from Alan Parekh web site and sourced the rest including the voltmeters off Ebay.


There are a couple of videos showing the clock working and synchronizing.