Seiko Kinetic Homemade wireless charger

[bmsm]

Hi everyone,

I’ve posted an entry at this magnificent community sharing my two Seiko 7M22-6A50. They are branded as Automatic Generating System that was later rebranded to Kinetic.

My problem started with the capacitor. The old ones didn’t last long, like 2 days max in one watch, hours in the other. So I bought the new lithium capacitor from cousinsuk that should last 180 days after full charge.

Problem, how to charge this?

Start reading about this and made a few tests. The Braun toothbrush charger worked but not very efficient. Phillips Imageo base charger didn’t work.

Start searching for alternatives to this. First the Seiko oficial chargers but they are rare and cost around 300$.

So, I stumble in one forum where someone bought a coil and assemble its own charger. The kit was a 3.3v 500mA wireless transmitter. I bought one but didn’t work. So I bought 12v 200mA max and 5v 600mA max and give it a try.

The 12v didn’t work but the 5v was a success.

My next experiment will by measuring how long it will take to make a full charge without burn the movement.



The transmitter



Female DC power adapter



And a normal AC-DC wall adapter with variable output to allow some adjustments.

This can burn the movement but I’ve 7 around here to play. I’m saying this because the watch gets real warm when charging.

Thanks

[Thrasher]

This is very cool, it's good to know people can still do things other than look at their phone.

[binbin]

Problem, how to charge this?

You could wear it.


I'm still waiting on a capacitor/battery from the U.S. to repair the one I'm working on. JulesBorel would not ship because of the lithium in the battery.


Do you think the field you are inducing in the coil in the watch will affect the magnet that is driven by the rotor?

Cheers,

[bmsm]

Still testing all this. Not really sure how all this will impact the movement parts. The technical document from the movement as some details about coil capacity but nothing about the magnet.

[Yoda]

I am not very much into electronics, but it seems that the warm watch means that the current is a bit too high, it will kill the movement in the long run.

How is it charged normally, apart from wearing it, is there a charger and what are the specs?

[bmsm]

Problem, how to charge this?

You could wear it.


I'm still waiting on a capacitor/battery from the U.S. to repair the one I'm working on. JulesBorel would not ship because of the lithium in the battery.


Do you think the field you are inducing in the coil in the watch will affect the magnet that is driven by the rotor?

Cheers,

I wear it. But with all the watches I've now it's getting +/- 1 day wrist time a week.

About the magnet, and according to Seiko Technical guide, swinging the watch 100 times I should get an extra 0.1V means the kinetic systems is working. Next I need to measure if the voltage is stable for 16 secs. If so, then we are good to go and there aren't issues with the system, otherwise I need to check more things.

[bmsm]

I am not very much into electronics, but it seems that the warm watch means that the current is a bit too high, it will kill the movement in the long run.

How is it charged normally, apart from wearing it, is there a charger and what are the specs?

I know its not good, its overcharging. Seiko had that in consideration when designed the movement, but there's a limit for everything. The coil resistance it's 400Ω and I'm for sure going behind that.

You can get an induction charger from Seiko (they are rare and expensive), can use shave or toothbrush base charger (but it's difficult to get the coil over the correct spot), buy a 60USD capacitor charger(you need to remove the battery) or you can assemble one

I'm searching for the Seiko charger specs that would be the best and safer approach, but meanwhile I'm just having fun and try have a working concept.

[Yoda]

Of course, having fun is the important thing!

[bmsm]

According to the Seiko manual, the charger output is 9v/0.5A and the alternating current magnetic field transmission(approximately 1 kHz). I'm not fare from that, I'm using 5v/0.6A.

They also expect the watch to get warm and even write this alert:

• Be careful with the temperature of the watch, when handing the watch to the customer.

319223647-Seiko-Kinetic-Energy-Supplier-YT02A-Manual.pdf

[blueradish]

Love this forum. If we have a problem, we solve it. Looking forward to following this journey.