[Series] Swapping the Saturn Clock to a silent movement ยท Replacing the Saturn Clock with a silent movement - Part 1

Popped the cover and this is what it looks like. The PCB is attached to the side, and its role is...


That blue gear down there has a stepped slope when seen from the side. When the white time gear matches the set time, it drops down with the leaf spring, completes the circuit, and the alarm sounds through the speaker.
ใด You can hear the leaf spring dropping.

Anyway, I concluded I can reuse the other parts, and as long as the housing and shape match, I can just swap the PCB that sends signals and power to keep all functions.

I searched AliExpress based on this, but couldn't find a matching part.

So I started a retail gacha.

Swept everything at Daiso. My cat is looking at me like 'Wtf are you doing;;'

Integrated types have the PCB and speaker attached, so they're useless for me since I want to keep the other functions. I need to use the original Saturn clock's speaker, switch, LED, and power.

Looks similar but can't be transplanted. Disqualified.

Next, I ripped open this one that looked somewhat similar.

Looks just like the Zut-clock. The LED and switch wires are out, only difference is the speaker is replaced by a bell-striking motor.



Opened the movement and even the housing and screw positions are identical. The PCB looks similar too. If you look closely, the coil sizes are different. Basically, the ticking 'step movement' on the left sends a signal every second, while the silent 'sweep motor' on the right sends signals multiple times a second. So you have to use the PCB and coil that handles those signals. Just swapping gears won't make it silent.
The silent movement is connected to the alarm switch and battery positive/negative from the left.
The original Zut-clock step motor is connected in the same order. No scientific proof, but I figured 'can't I just snip the wires and move them?' and cut them immediately.

Strip the insulation, connect in the same order, and test?

It works lol

Alarm sounds great too.

Old movement is useless now, so I can toss it.

A gruesome scene of organ transplantation.

Twist the wires well.

Finish roughly with electrical tape. There's one more thing to do next.

Pop off the time/alarm adjustment knobs from the old movement...

...and transplant them to the new one.

Like this.

Once done, screw it back into its original spot. (Again, I moved the whole silent movement housing and even the screw holes lined up perfectly.)

Attach top and bottom plates, tighten screws.
Sync the alarm and zero-point, then put the hands on. Spin the alarm dial gently, stop where you hear the leaf spring drop, and slam them all in facing 12 o'clock.

Then put it back together, but watch out: the white ring on the right is slightly sloped. The narrower diameter side goes up towards the clock. The clock's LED needs to be installed outside the white ring.

Attach the top bar, bell, and feet... Assembly done! Now for the final test to see if it keeps time.

Dammit, the second hand is catching on the minute hand.
Popping the top again...
There's interference there. Let's straighten the 'waist' of the second hand a bit.

While I'm at it, the alarm and hour hands were interfering too, so I straightened them. Reassembling.
Tested and it's smooth as butter.
Verified the alarm sounds good too. Done. There's about a 5-minute error, but that's just the nature of analog alarms, nothing I can do.
"Zut-Gal users are impressed by the successful DIY 'organ transplant' but are low-key disappointed the OP didn't end up with a broken clock for the memes."
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