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I find long distance reception of longwave radio signals (LW DX) fascinating, there are still a few interesting high-power stations that can be heard internatio

I find long distance reception of longwave radio signals (LW DX) fascinating, there are still a few interesting high-power stations that can be heard internationally. The radio is also easy to build - low-noise audio frequency amplifiers and 24-bit ADCs should do. Unfortunately it's extremely impractical for us city dwellers due to the huge antenna required for DXing and the deafening noise from switched-mode or digital devices. It only takes a single bad PSU to trash the LW spectrum.

dragontamer 5y ago
I'm no antenna expert, but it was my understanding that the WWVB signal could be received on a homecrafted Ferrite Rod antenna. http://prc68.com/I/Loop.shtml http://prc68.com/I/Loop.shtml Antenna of this type are a large ferrite rod, with a number of copper loops forming an effective inductor. With some capacitors, you can filter out other signals (forming a notch at the 60,000 Hz signal to get the WWVB) Not that I've done this before nor am I any kind of expert on radio. But... its not an especially large antenna from my understanding. -------- I can appreciate the issues of noise. The 60,000 Hz signal is a 1-baud (lol) signal, one-bit every second. So you need 60-seconds to transfer the 60-bits of time information to the receiver. Any noise within that 60 seconds could destroy the signal and make it inaccurate.
- segfaultbuserr 5y ago
  A simple ferrite rod antenna is the standard if you're in a covered zone. If you want to pick up distant signals you'll need something better. I've previously heard some amateur radio operators use many meters of random wires around one's backyard, that was what I imagined to be a "large antenna," so I didn't look further. But I just found an ARRL article [0], > A long wire sometimes works if directly connected to the antenna jack on the transceiver. In reality, a 500 foot long wire is a very short wire (less than 0.1 λ) on 2200 meters. A preferable option is to use a small loop antenna and a preamp. These loops are generally about 2 meters in diameter, and a number of designs can be found on the LF Web sites. Unlike any practical wire antenna an amateur can erect, a loop will not take up much real estate and can be made directional to reduce interference. Once you have your antenna up and can receive commercial longwave stations such as CFH and DCF39, you have sufficient receiver sensitivity and you are now well on your way to receiving amateur signals on LF. Looks like a small, 2-meter magnetic loop antenna paired with a preamp should work well. Perhaps I should give it a shot one day. Of course, to transmit a signal (2200 meter is 136 kHz, which is an amateur band), it's a completely different story. [0] http://www.arrl.org/files/file/Technology/pdf/craig.pdf http://www.arrl.org/files/file/Technology/pdf/craig.pdf
- bb88 5y ago
  Universal Solder in Canada sells just a kit like that. https://www.universal-solder.ca/product/canaduino-60khz-atomic-clock-receiver-module-wwvb-msf-jjy60/ https://www.universal-solder.ca/product/canaduino-60khz-atom...

dragontamer 5y ago

I'm no antenna expert, but it was my understanding that the WWVB signal could be received on a homecrafted Ferrite Rod antenna. http://prc68.com/I/Loop.shtml http://prc68.com/I/Loop.shtml Antenna of this type are a large ferrite rod, with a number of copper loops forming an effective inductor. With some capacitors, you can filter out other signals (forming a notch at the 60,000 Hz signal to get the WWVB) Not that I've done this before nor am I any kind of expert on radio. But... its not an especially large antenna from my understanding. -------- I can appreciate the issues of noise. The 60,000 Hz signal is a 1-baud (lol) signal, one-bit every second. So you need 60-seconds to transfer the 60-bits of time information to the receiver. Any noise within that 60 seconds could destroy the signal and make it inaccurate.

segfaultbuserr 5y ago
A simple ferrite rod antenna is the standard if you're in a covered zone. If you want to pick up distant signals you'll need something better. I've previously heard some amateur radio operators use many meters of random wires around one's backyard, that was what I imagined to be a "large antenna," so I didn't look further. But I just found an ARRL article [0], > A long wire sometimes works if directly connected to the antenna jack on the transceiver. In reality, a 500 foot long wire is a very short wire (less than 0.1 λ) on 2200 meters. A preferable option is to use a small loop antenna and a preamp. These loops are generally about 2 meters in diameter, and a number of designs can be found on the LF Web sites. Unlike any practical wire antenna an amateur can erect, a loop will not take up much real estate and can be made directional to reduce interference. Once you have your antenna up and can receive commercial longwave stations such as CFH and DCF39, you have sufficient receiver sensitivity and you are now well on your way to receiving amateur signals on LF. Looks like a small, 2-meter magnetic loop antenna paired with a preamp should work well. Perhaps I should give it a shot one day. Of course, to transmit a signal (2200 meter is 136 kHz, which is an amateur band), it's a completely different story. [0] http://www.arrl.org/files/file/Technology/pdf/craig.pdf http://www.arrl.org/files/file/Technology/pdf/craig.pdf
bb88 5y ago
Universal Solder in Canada sells just a kit like that. https://www.universal-solder.ca/product/canaduino-60khz-atomic-clock-receiver-module-wwvb-msf-jjy60/ https://www.universal-solder.ca/product/canaduino-60khz-atom...