WWVB Receiver Antenna Project

Discussion in 'Wireless & RF Design' started by wr8y, Mar 1, 2009.

  1. wr8y

    Thread Starter Active Member

    Sep 16, 2008
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    I was given this working WWVB time receiver. But the antenna was not available and documentation is poor.

    I live in central Georgia, USA - what kind of antenna should I build for it? Can I get away without a preamp if I am happy to just have night time reception?

    Help! I'v worked in radio for 28 years, but know nothing about propagation at 60 kHz!
     
  2. SgtWookie

    Expert

    Jul 17, 2007
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  3. wr8y

    Thread Starter Active Member

    Sep 16, 2008
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    Yea, but what is the board? Doesn't sound like it's a preamp with a CRYSTAL on it!

    I did find that rod at Amidon's website. $20 each!
     
  4. SgtWookie

    Expert

    Jul 17, 2007
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    That's the C-Max. You have to scroll down the page about halfway. And lookie, there's an xtal on the board! One of those cylindrically packaged thingies. ;)

    You want good AND cheap? :confused: :D

    I suppose you could always scrounge around for something else, but looks like Brooke spent a fair amount of time on it, and came up with something he feels works pretty optimally - and unless you happen to have a network analyzer kicking around to help tweak on things, you might just want to go with his suggestion.

    Look at it this way, a $20 ferrite rod is a heck of a lot cheaper than a $15,000 network analyzer. ;)
     
  5. wr8y

    Thread Starter Active Member

    Sep 16, 2008
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    That is my point - why? Preamps need no crystals.

    I guess I should go back and read some more.

    EDIT: Oh, I see. The C-Max is a RECEIVER. Don't need that, just need an antenna and preamp - the pic I posted IS my receiver and clock.
     
  6. SgtWookie

    Expert

    Jul 17, 2007
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    It's an 11.0592 MHz crystal for an 8051-type uC.
    :)

    Yes, there are several items kind of "lumped together" on the page; takes a bit of reading (or a couple read-throughs) to sort through it.
     
  7. wr8y

    Thread Starter Active Member

    Sep 16, 2008
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    This may not be as hard as I thought. I connected to a 66 foot dipole antenna with no preamp. The receiver is locked to the carrier - but the signal to noise ratio (as indicated by the receiver's decoder) is on the edge. The receiver achieved lock right after sundown, but it cannot decode enough bits in a row to set the clock.

    The dipole is in the attic, coupling to too many noise sources, I suspect. I think I just need a modest preamp and an outside antenna.
     
  8. DickCappels

    Moderator

    Aug 21, 2008
    2,648
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    Easy things you can do to improve the signal:

    Change the antenna's direction.

    Change your dipole (I am guessing center fed) to an end-fed longwire and sure your receiver is connected to a good ground.

    Connect a loading coil or "match box" between the antenna and the receiver. (Search the web for examples).
     
  9. wr8y

    Thread Starter Active Member

    Sep 16, 2008
    232
    1
    I thought of that Dick, but I want to build something small, like the original ($200!) antenna. I am thinking of finding an old AM receiver, taking the ferrite rod out of it, and making something like what's in post 2.

    I also found a preamp I think I like (how hard can it be to build a preamp for 60 kHz!?!) http://www.alan.melia.btinternet.co.uk/receive.htm

    Anyway....

    I got up this morning, and WOW! the thing, just before sunrise, with the 5,000 watt 1320 AM station 1,000 feet away on the air - had locked and was showing no bit errors at all!!! I suspect the signal has, by now, (I'm at work typing this) faded away - but the point is, this won't be as hard as I thought.
     
    Last edited: Mar 2, 2009
  10. wr8y

    Thread Starter Active Member

    Sep 16, 2008
    232
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  11. wr8y

    Thread Starter Active Member

    Sep 16, 2008
    232
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    Well, it turns out this is easier than ever. I tried a 40 foot wire run out of the receiver and up to the attic. I didn't want a lot of wire running around the house, but this runs right up to the attic and is not notice able or in the way at all.

    Good signal and lock soon after sundown!
     
  12. RAH1379

    Well-Known Member

    Dec 13, 2005
    69
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    i would go with a small loop antenna ( called small because it is less than 1/10th wavelength) it responds to the magnetic portion of the wave instead of the electric portion as most common antennas do. you can find plans by doing a search for joseph carr, he has them on his website. They are small enough to be portable , bi-directional so you can null out distortion,interference,and stronger stations off the side of the antenna. It is basically a wooden cross brace supporting a loop of many turns of insulated wire, with a variable capacitor at the feedpoint to turn it. They work really good at medium wave, longwave, and vlf, elf when you don't have room for a large antenna.If i remember right joe's website is dx.com but i could be wrong.
     
    Last edited: Apr 16, 2009
  13. RAH1379

    Well-Known Member

    Dec 13, 2005
    69
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    Help! I'v worked in radio for 28 years, but know nothing about propagation at 60 kHz![/QUOTE]

    hope you like staying up late, expect no reception until grayline passes(grayline is sunset) and the best reception about 2 or 3 am. If your receiver is tunable you can find lots of beacons in the longwave band, to test your antenna.
     
  14. RAH1379

    Well-Known Member

    Dec 13, 2005
    69
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    I just looked at that sight and that is the antenna i was talking about, although made by someone different. They work very good, i have made a couple of them over the years for bc band reception and shortwave, but not for 60khz, i use wwv in the hf bands when i need a time signal.
     
  15. RAH1379

    Well-Known Member

    Dec 13, 2005
    69
    1
    Anyone here into shortwave listening? i would like to hear about your radios if so. I have been listening to shortwave since i was a kid (im 54 now) and have had and built many different radios and antennas.I use a Yaesu frg 7700 with a few modifications,i have lots of others but its my favorite.
     
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