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Bob, is this something I could possibly be able to use in this application?
Where does one find such high-impedance coax? As an alternative, would it be possible to put an active device up near the antenna that would act as a buffer to feed a low-impedance line? Dave "Bob Lewis (AA4PB)" wrote in message ... If the antenna is the typical end-fed wire then the impedance will be very high. Most AM radios have a high impedance input designed to match a random wire like that. If you use coax, the capacitance of the coax (center conductor to shield) will essentially short most of the signal to ground and little will get to the receiver. If you've ever opened up the coax used on car radios you'll find that it is a special high impedance coax. A small wire fits loosly thru an insulated tube with the shield around the outside. This keeps a relatively large spacing between the center conductor and the shield in order to minimize capacitance. |
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