captainkirksdog
Member
Does anyone have a "crystal-radio", (i.e. NO power supply, NO batteries, just the signal itself) that will bring in WWV? I've built a few crystal sets, but try as I might, I can't tune in WWV. Any help?? Thanks.
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In practical terms. The signal strength of the radio signal at the antenna terminals is in microvolts, that is 1 one millionth of a volt. If you consider a AA battery is 1.5 volts, you can see the difference. A pair of headphones probabley needs a few tenths of a volt to be heard. So a receiver that has amplification(requires power) and some selectivity(separates the stations)captainkirksdog said:Does anyone have a "crystal-radio", (i.e. NO power supply, NO batteries, just the signal itself) that will bring in WWV? I've built a few crystal sets, but try as I might, I can't tune in WWV. Any help?? Thanks.
I think you can improve on that by using source and load impedance matching techniques on the coil, but a crystal set still needs a pretty strong signal. WWV transmits 2.5kW at 2.5MHz and 20MHz, and 10kW at 5, 10, and 15MHz. This is pretty weak compared to clear channel AM stations, which transmit at least 50kW.k7elp60 said:In practical terms. The signal strength of the radio signal at the antenna terminals is in microvolts, that is 1 one millionth of a volt. If you consider a AA battery is 1.5 volts, you can see the difference. A pair of headphones probabley needs a few tenths of a volt to be heard. So a receiver that has amplification(requires power) and some selectivity(separates the stations)
is a minimum requirement.