Charging a Seiko Kinetic Without the $$$ Seiko YT02A $$$

I have two Seiko Kinetic, one a cal. 5M85 GMT and the other a cal. 7D48 Auto Relay Perpetual. With well over 100 watches they're a PITA to keep charged, a problem common to Seiko Kinetic owners with watch collections. If you don't wear them at least several times per week with a fairly active lifestyle, they drain down completely. They're made to be worn 12-16 hours per day, at least 5 days per week, preferably 7.The 5M85 is made to hold about 6 months charge in it's Lithium Ion battery when fully charged. The Auto Relay Perpatual is made to run four years in hibernation mode when fully charged. It's been less of a PITA. Seiko quit using capacitors very early on with their kinetics. In these old ones, they're replaced with a Li-Ion made to fit it when serviced. After the first few years, all the kinetics were fitted with Li-Ion. All Seiko's kinetics can be induction charged if you get the coil in a charger with the right frequency range in close enough proximity to the movement's charging coil. Location of the movement charging coil varies by movement family. In other words, the location of it in my 5M85 is different from its location in my 7D48.

Seiko made an induction charger for service center and watchmaker use, the YT02A. A look at its top shows the orientation for each kinetic caliber family. Its induction coil is off-center and the crown orientation for the movement family positions the watch's coil over it. It can fully charge any Seiko kinetic movement with a healthy cell in 3.5 hours or less, from zero energy charge. While they were more available twenty years ago at somewhat reasonable prices, they quickly rose to over $200 ten years ago, and used ones easily sell for $300 now, if you can find one. A recent ePrey listing went almost immediately for $300 plus $18 shipping, plus sales tax. About $350 for a kinetic induction charger is outrageous.



Common and very cheap cell phone and smart watch chargers will not work. They are "Qi Compliant" with a handshake required from the device being charged to control the charging cycle. I have one for charging Wii controllers and the handshake includes the induction charger pad showing controller presence and whether it's fully charged or not. Seiko's kinetics have no means to handshake with one. The "cell phone charger" question is asked ad infinitum ad nauseam by countless who are too lazy to read the kinetic charging threads on forums such as WUS. You cannot get through any of the (going on) 28 pages of postings about kinetic induction charging without seeing at least one of them.

There are alternatives to the now obscenely overpriced, out of production Seiko induction charger. I've got two of them, but unlike the Seiko charger, they're sensitive to watch positioning on them. One of the common and relatively easy solutions was the Philips Imageo rechargeable tea light set that has three induction charging pockets for the tea lights. They're out of production and have been for a number of years. Found some on ePrey and they're selling for over $100. If you find a working one at a Goodwill store or garage sale, it will probably be much less. Current rechargeable tea lights are not by induction, they're direct connection with USB chargers. Been down that path already.

Dakota Watch made the REQ, a rechargeable watch without the Qi control, and still has an induction charger for it. This charger will work with Seiko Kinetic. The issue is finding the sweet spot on which to place the Seiko watch and it's sensitive to watch positioning. The Dakota REQ charger currently sells for $50.



I was unable to get it to reliably charge the 5M85 GMT (more on that later), but it is apparently charging the 7D48 Auto Relay Perpetual as shown in the photo. If I allow the 7D48 to go into hibernation and place it on the charger unplugged, as soon as I plug it in, the watch comes out of hibernation. I've been able to repeat this behavior several times to verify it wasn't some motion on my part that did it. There is undoubtedly a sweet spot with optimal charging rate that I will eventually find.

Another solution has been the use of Braun toothbrush induction chargers. One of the more reliable has been the now discontinued 4728 charger. These can be found on ePrey for pretty cheap and they're plentiful. Inverting it to get the watch's coil closer to the charger's coil works best as it's in the charger base, not the post on which the toothbrush sits.



I was able to get this to work with my 5M85 GMT as shown with the "9" positioned at the left edge of the circle on the charger bottom. The 5M8x movement charging coil is approximately under the 7 - 10 on the dial (if the crown is at the 3). With my inability to find a sweet spot on the Dakota, I was beginning to wonder if I needed to replace its Li-Ion cell, which gets into movement disassembly I'd much prefer to avoid. About 3 days on this Braun charger as shown got it from double-ticking to a full charge. It's been off the Braun charger two days now, and it's still showing full 6 month charge level (seconds hand sweeps 30 seconds when charge button is pushed).



I will make a homemade wood stand for the inverted Braun charger that allows putting the watch on it more elegantly than depicted.

Unfortunately, the 7D48 has no method to display its charge status. It will do the double-tick when power is nearly exhausted, but that doesn't occur if it's in hibernation. From full charge with a healthy battery, it's supposed to be able to hibernate for four years. I suppose that is why Seiko didn't see fit to provide a charge status display or method. They didn't imagine someone would let one sit dormant for four years. While resetting the date and time on the GMT isn't a big deal, doing so on the Perpetual and getting it into the Leap Year cycle is a PITA. I've tried to avoid it running down completely but haven't always been successful. Wore it so little versus the recommended 10 hours per day, 5-7 days per week eventually let the battery drain down.

Finding the sweet spot to optimize location and orientation with any of the various work-arounds can be done using a Kill-A-Watt P4400 meter in line with the charger. Dakota and toothbrush charger alone will have near zero power consumption. When charging a watch, power consumption measurably goes up. I don't have one, but it was ordered yesterday and should arrive next week. In the meantime I thought what I'd discovered over the past several weeks would be of interest.