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I have built a large ferrite loopstick antenna based off this video. I live in Washington state and am trying to receive and decode WWVB. I can get my antenna to resonate at 60kHz with ~700 pF of capacitance. I am lost on the receiver/preamp portion, I have tried to build receivers but I seem to just get noise on the other end. I tried using this design, but I get noise on the other end. Does anyone know why this design didn't work? At the time I implemented it on a protoboard so maybe it was parasitic elements?

I also tried this design, but at the time I was using a small antenna and couldn't get it to work. At this point I have a general idea of how to design my own receiver, but was wondering if anyone had some books to recommend or some good example circuits. I think designing my own receiver from scratch might be necessary, but am a little confused where to start. I want to shy away from superheterodyne receivers/ using crystals because I don't quite understand that, and I don't have the parts. I have been told a TRF design should work, but I've had no success. I have confirmed my antenna works in lab using a signal generator, but I can't see the WWVB signal on an oscilloscope with my receiver design attempts.

I used a JFET input op amp in an open loop configuration as a amplifier. On a spectrometer I was able to see the 60kHz peak. When hooked up to an oscilloscope the signal was just garbage, this isn't surprising because of the lack of filtering. This signals to me that I can receive the signal at least, but as I mentioned before I can't get a clean signal to look at.

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    $\begingroup$ “Some good resources” is pretty broad, and in fact we generally don't allow that kind of question. Can you edit this question to narrow it down? For example, you could provide schematics and pictures for one or more of your receivers and ask if something is missing from their design such that they won't work. $\endgroup$
    – Kevin Reid AG6YO
    Commented May 3, 2023 at 0:54
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    $\begingroup$ I tried to narrow my question down. I suppose my question by nature is a little broad, but hopefully this is better. $\endgroup$
    – Max686
    Commented May 3, 2023 at 1:44
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    $\begingroup$ Thank you for the additional details. Please upload relevant images (with credit!) into the question editor — questions should not need external links to be understood (since they break not infrequently). $\endgroup$
    – Kevin Reid AG6YO
    Commented May 3, 2023 at 3:26
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    $\begingroup$ 1. How do you know it's resonant at 60 kHz? 2. An open loop op-amp is not what you want (ever). Rather make a low gain non-inverting buffer amplifier. Take care of the DC bias of everything - if you have a single supply rail, use a DC blocking cap and then a resistor divider to bias the +input to Vcc/2. 3. A scope displays DC to N MHz all at once, to show a clear sine wave the signal would have to be huge, stronger than all the noise in the scope bandwidth while for a radio-controlled clock to receive it it only needs to be stronger than the noise in 100 Hz bandwidth. $\endgroup$
    – tomnexus
    Commented May 4, 2023 at 5:57
  • $\begingroup$ See also this project, using a Raspberry Pi Pico to digitise and slightly process the very similar MSF signal at 60 kHz. Even if you don't digitise it like this, the article has some useful notes about antenna and amplifier design. $\endgroup$
    – tomnexus
    Commented May 5, 2023 at 15:58

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One problem with breadboard construction involves the high-gain TRF signal chain @ 60 kHz...you get 60kHz feedback from breadboard back to loop antenna. It may help to put a low-gain amplifier at the antenna (enough to drive a 60 kHz signal driving a shielded cable) to the remote amplifier chain.

It also helps to look for WWVB signal at night when signal levels rise, and when local noise sources tend to be quieter. Below is a plot showing WWVB signal amplitude versus time. Each amplitude point is plotted at the end of each second: WWVB amplitude passing from night to day
The signal amplifier chain here was embedded in a metal box, and fed to a microcontroller where A-to-D conversion was done, and amplitude output at the end of each second.
It appears that three plots are overlaid, but be aware that a "sync" (or "marker") symbol has lowest accumulated amplitude, a "one" symbol has intermediate amplitude, and a "zero" symbol has highest amplitude.

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