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Thread: 60 khz Transmitter

  1. #1
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    Default 60 khz Transmitter

    Does anybody know how I can get my hands on, or make a 60 khz FM transmitter? My watch automaticaly updates itself to the atomic clock using the WWVB station. However at my current location I can't get the signal. I have been playing around with GPS receivers and the Arduino and I'm thinking I can use them to update the time on my watch. After a couple of hours of searching the web, I cannot find an FM transmitter that broadcasts that low.
    I would appreciate any ingights or advice from the group.
    Thanks,
    Mike

  2. #2
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    Default Re: 60 khz Transmitter

    Hi:
    Mike, you should have no problem receiving the WWVB signal in Junction City. The transmitter is near Ft. Collins, CO, maybe 300 miles from you.

    Take a look at this website:

    http://www.nist.gov/physlab/div847/grp40/wwvb.cfm
    http://en.wikipedia.org/wiki/WWVB

    The modulation is not FM, it is pulse width modulated.

    Your watch should listen for the signal between 12 midnight and 6 am. If you are not resetting correctly, I suggest something may be wrong with the watch or there may be a setting on it that turns the receiver on or off. Also, you might try hanging the watch in a west facing window at night.

    I am in Yuma, AZ and have 3 clocks in the motorhome. They all receive the signal with no problem. While we were traveling the East Coast last summer/fall, the clocks all received the signal while we were in Ontario, Canada and in Maine.
    Last edited by IdunBenhad; 04-12-2010 at 09:41 AM.
    [B][I][U]Idun

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    Default Re: 60 khz Transmitter

    WWVB works up here in Minnesota though depending on the building construction, you may need to go outside. All RF clocks that I’ve seen have a way to force and immediate update, though they’ll try to update in the middle of each night and that time is configurable too.

    Making a transmitter at 60KHz is pretty easy though. I did it with a single MOS chip to simulate the DCF77 (77KHz) time transmitter of Frankfurt Germany. The antenna was just a retuned loop stick antenna from an AM radio. I used a PC connected to the NIST Internet Time Service to generate the PWM.

    At these low frequencies, the signal is somewhat of a line of sight in that if you’re in too deep of a hole, you might not get a strong enough signal. You might try just getting to a higher location and away from any buildings. Though I would think that with a 70 kilo watt transmitter so close, you pretty much shouldn’t have any dead spots.
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  4. #4
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    Default Re: 60 khz Transmitter

    Hi:
    The signal loss behind a hill is a good probability. Junction City, KS is very hilly. I have been through there many times and my grandson-in-law was stationed at Ft. Riley, which is almost surrounded by hills. Mike may live behind one of those hills.

    I can see Mike running up to the top of one of the hills every midnight just to set his watch!!

    By the way, I have found that most of these WWVB clocks/watches are very accurate even when they are not reset periodically by the radio signal.

    Ernie: The 77 khz transmitter and the way you achieved the modulation from the internet in very interesting, but that sure is a lot of work just to get the time signal!
    [B][I][U]Idun

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    Default Re: 60 khz Transmitter

    Quote Originally Posted by IdunBenhad View Post
    Ernie: The 77 khz transmitter and the way you achieved the modulation from the internet in very interesting, but that sure is a lot of work just to get the time signal!
    It was a hack job that was needed for a Dutch product. At the time, I had no real experience with designing transmitters. It was only used in my lab. I have no idea about the efficiency or what kind of other crap it was spewing in the air. It did the job and we verified the products actual operation in Amsterdam. Everybody was happy and thought I knew what I was doing.
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  6. #6
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    Default Re: 60 khz Transmitter

    Hi:
    You know the old saying:

    "If you can't impress 'em with brilliance, dazzle them with BS"
    [B][I][U]Idun

  7. #7
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    Default Re: 60 khz Transmitter

    Making a transmitter at 60KHz is pretty easy though. I did it with a single MOS chip to simulate the DCF77 (77KHz) time transmitter of Frankfurt Germany. The antenna was just a retuned loop stick antenna from an AM radio. I used a PC connected to the NIST Internet Time Service to generate the PWM.
    I too am interested in this project. I would appreciate more info if you have any.
    The signal loss behind a hill is a good probability. Junction City, KS is very hilly. I have been through there many times and my grandson-in-law was stationed at Ft. Riley, which is almost surrounded by hills. Mike may live behind one of those hills.
    I too am stationed at Ft. Riley however, I am not there now. I am current in a place that starts with "I". I'll let you all do the guessing as to where that is. I fugured something like this might be a fun project to attempt in my spare time.

  8. #8
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    Default Re: 60 khz Transmitter

    Hi:
    First, good luck and stay safe, Mike. Thanks for your service. Hopefully, you will soon be stationed in a place that starts with "K".

    And, you certainly are behind a "big hill"!

    Ernie has some good ideas. That would be a fun project. You could use his ideas and set your watch watch from the internet.

    I saw, elsewhere in the net, using a 555 timer as a transmitter. You could find an old transistor radio with the ferrite core antenna and salvage that. By padding it with capacitors, you tune it down to 60 khz. It might take quite a bit of capacitance to move it from 550 khz down, but it could be done. I think Ernie did that, too.

    Have fun, and keep us informed as to what you are doing.

    Again,THANKS
    [B][I][U]Idun

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    Default Re: 60 khz Transmitter

    Quote Originally Posted by IdunBenhad View Post
    Hi:
    You know the old saying:

    "If you can't impress 'em with brilliance, dazzle them with BS"
    Words to live by........... I have always loved that one!!!!!!!

  10. #10
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    Default Re: 60 khz Transmitter

    Ernie,
    Which 4060 chip did you use. I did a search on mouser and came up with an amplifier ic and a counter ic. I assume you used the amplifier since we are talking about RF. Also, how did you hook it up to the PC? I don't see any references to it in the schematic. You have to break it down to "Barney" level for me.
    Thanks,
    Mike

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