MultiBand 6 – What is it?


Casio has a line of wristwatches that utilizes something called Multiband 6.  What that is is a radio receiver which allows the watch to receive a signal from WWVB in Fort Collins Colorado which keeps the watch synchronized with their atomic oscillators.  There are also transmitters in the UK, Germany, China, and Japan which provide the same service.  If you have a Multiband 6 watch and travel it should sync with the perfect time most anywhere.  The actual definition of Multiband 6 is that is the number of transmitters that the watch can receive from.  There are six such transmitters.

60 kHz Transmitters (click pics to enlarge)

The station WWVB is run by the National Institute of Standards and Technology (NIST) which maintains the time and frequency standards and makes them available to the American public.   The signal is broadcast on a frequency of 60kHz with a 70kW signal.

NIST was on the chopping block about a year ago by our esteemed government who decided to shut it down.  Then at the last minute it got a reprieve.  While losing the ability to sync a Casio G-Shock may not be catastrophic there are many time sensitive computer and clock devices that even the US government and scientific fields NEED.  Shutting down would have been problematic.  This web page gives a list of manufacturers and what services they use WWVB for.  Much of it is academia and scientific research and GPS usage. Shut down NIST and GPS’s might act weird.


In a similar vein many clocks on AC use a chip that is timed by the 60 Hz AC cycle in our electrical grids and in fact I recall seeing articles about a year ago that European clocks were losing time due to 50 and 60 Hz frequency cycles.  Depending on where the power was coming from your clocks could be running 6 or so minutes slow a day.

Back in the day a company called Telechron made clocks that kept awesome time by using a synchronous motor that used the 60 Hz cycle for timing.   Using frequency to keeps things timed has been utilized for ages.  This is not a new technology.


Anyway back to the coverage zones.  The maps above from Casio make it look like you can always get the signal.  As I type this it is about 0730 which is 1230 UTC.  Here’s what the NIST webpage says the signal is like at 1200 UTC under normal condition.

Multiband 6 coverage

Yikes.  I’m left out as a resident of Eastern North Carolina.  The default sync time on the watches though is usually the middle of the night.  Here is 0400 UTC which is about 2300 or 2400 EST depending on daylight savings time.

Multiband 6 Coverage night

MUCH BETTER COVERAGE.  So this is typically why your G shock wants to sync the time in the middle of the night.   Even with this coverage I find that my watch seldom syncs in North Carolina unless I put it in the “magic spots” in the house.  One such magic place is between the slats of my bedroom window blinds about eye height.



I wish I were joking about this but I’m not.  That is where I have to put the watch at night if I want to ensure it will sync.  Also setting it outside on the back porch will generally ensure a good solid  radio signal and sync.

I recently went to Yuma AZ for work for a week or so and the watch sync’d up every single night in the hotel room and hotel rooms are generally Faraday cages.   Anyway Multiband 6 works way better out West than it does in the Croatan National Forest in North Carolina.

Hey, can’t have everything I guess.  At the moment this is my only Multiband 6 watch so I’m curious if others have better receivers or not.

As a licensed Ham Radio operator I get a gigantic kick out of knowing that my wristwatch is synchronized from a long wave radio signal.  Just to put that in perspective, Short Wave radio is about 3-30 MHz and Medium Wave (which is what you call AM radio) is about 525 – 1705 kHz.  Long wave is anything below medium wave so 60 kHz falls within the long wave radio spectrum.

Hope that you learned something about your Multiband 6 Casio’s that you did not know.  As a Ham Radio guy I can tell you that radio signals are big fun!  Enjoy!


12 thoughts on “MultiBand 6 – What is it?

  1. Wanderer16 (GSHOCK forum) WUS

    Enjoyed you blog. I have 7 MB6 casios. I live one time zone west of you in south Alabama and mine always sync at night if they are in my watch case on my dresser face up. My 5610, which is my favorite, if left on its side outside the case on the dresser will fail to sync, but if in my window which faces south west and laying on its side will sync every time so I think watch position plays a role as well. If you don’t yet have a square or a ProTrek go ahead and do yourself a favor. I recently got a ProTrek with moon and tide functions, which fed my inner geek also!! If your a geek you will also need the NASA approved models and I highly recommend the DW-5600E for a non solar addition!!

    1. John Hagensieker Post author

      Thanks for the info! I’ll look into the DW-5600E. I have a GWG1000-1A3 and GW6900-1 inbound as well.

  2. Jack Warner JR.

    John I got to tell you this was great information I know this post is a year or two old but the maps were wonderful especially the ones in red which showed the coverage zones at different parts of the day!
    Please forgive me for my long run on sentences because I’m typing this through the voice to text feature just be aware of that
    Yes, I too have some multiband watches made by Casio G-Shock two of them AR ar G-Shock and two of them are Casio protrek this was so funny to me for the one and only reason when I saw your picture of your watch in between your blinds I have absolutely no doubt you are not kidding because I live in Georgia on the Westside which is the opposite side near North Carolina and I have to do this exact same thing every single night if I want my watch to synchronize with Fort Collins Colorado almost down to the exact same spot and I height at my eyes height and my blinds are no kidding 100% the exact same brand of blinds the color is very similar as well so it threw me for a loop when I found what may be the only other person doing this to synchronize their what March I got to tell you I bet after reading this you and I are not the only ones so if I don’t put my watch on the blinds in the window it will maybe sink once or twice a month but every night it will sink if I place it in this one spot but it has to be at night which according to your map make sense because the signal is stronger if I try it during the day it will not work I know you know the signal strength display on the watch L1 L2 L3 and during the night it is L-3 and de L1 this is such a coincidence You Are Not Alone I’ve got one question for you the window I have to put mine in faces West from me in Georgia towards Fort Collins Colorado is your window facing west or Northwest

    1. John Hagensieker Post author

      Actually my window faces NNE. It doesn’t make sense at all but it works! Thanks for the post. Great observations.

  3. Jack Warner JR.

    If you see my comment above perhaps you could send me an email to inform me you have replied…

    I am aware this is a little older thread… do you even still on this watch and are you still doing the same thing I am to sync it. Thanks Jack

  4. Jack Warner JR.

    Oh wow John that was super fast I can’t even believe you were able to read my comment and respond that quickly are you a robot haha I thought it would make you feel better knowing someone is having the same problem on the westside of Georgia which could be 6/8 hours from you or maybe less depending where in North Carolina you are I read a comment above from a gentleman in Alabama it sounded like he got a little better signal than us on his dresser but I know I must be by a window or Outdoors on a porch You Are Not Alone I just received two new G-Shocks today 9100 and 6900

    1. John Hagensieker Post author

      As a ham radio guy I get a kick out of knowing my watch syncs with long wave radio. Like you noted my watch just about only syncs if I put it on the window blinds and then won’t sync until midnight or after. I think the watches begin trying to sync at midnight and try a few times. Can’t remember how many attempts or the frequency of attempts.

  5. Brad

    Multiband 6 watches have ferrite rod antennas which are very directional in terms of reception. That is why Casio recommends in the manual of all their Multiband 6 watches to make the 12 o’clock side of the watch face through an open window in the direction of the nearest tower. That position aligns the ferrite rod antenna perpendicular to the signal, the orientation that reception is strongest.

    The easiest method though may just be wearing your watch to bed. Your body can act as a decent antenna due to water, electrolytes, and skin surface area which gives it some conductive and capacitive abilities. My bed just so happens to be next to a western facing window as well (the direction of the Fort Collins tower from me, I live in Michigan), so I wear my GWM5610 to sleep which is also pretty comfortable. If I do this it has nearly always synced first try at exactly 12:04am, suggesting that the signal reception is very strong. I wake up knowing my morning alarm on my wrist is accurate to the second!

    It may work well even if you don’t face near an open window or the correct orientation at all, but I haven’t tested this much. I’ve also had significant luck putting the watch around an iron or steel pipe in the same or similar orientation to the 12 o’clock position, such as around a pullup bar, window drape rod, or bike frame. You can also try either of these methods and force the sync yourself anytime. Try not to move too much if it’s on your wrist though. Good luck!

  6. Titus

    Hi John, I’m not a big science person. But the other day I was thinking, if I have a GW6900 with me and I’m lost in the forest, can the watch help people detect my location or can I send a rescue signal from the watch? Very curious to know. Thanks.

  7. David

    Hi John,

    I have a Casio Lineage MB6 with titanium case and band. It syncs every night from Seattle, but I’m even more impressed that when I recently traveled to Ecuador, it synced about 50% of the time from Quito, and most nights from the Galapagos. Both cases just from the bedside table. I love the watch!

  8. Henning

    I own a casio wave ceptor, don’t know if it’s MB6 or another kind of receiver.
    I live in northwestern germany and my watch always syncs up at 3 in the morning like… clockwork. 😀 Doesn’t matter where it’s placed. On my desk, nightstand, in the kitchen, always syncing.

    But – i recently travelled to the UK and it would not sync up for the life of me. No matter where i placed it and not manually or automatically. Granted, i only tried it in the hotel room. In the manual it says that there is a transmitter in the UK to recieve from.

    Thanks for the article, thinking of bying a casio rangemaster! Cheers from germany.


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