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#1
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Antenna matching
Hi there, is antenna matching important for receiving as much as for
transmitting. Sorry if this is a dumb question. P |
#2
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"Peter" wrote:
Hi there, is antenna matching important for receiving as much as for transmitting. Sorry if this is a dumb question. Well it's on topic and not about the latest conspiracy theory, so it's not a dumb question. The short answer is no. The longer answer is that antenna matching with a transmitter is about energy transfer -- a mismatched load will cause power to be reflected back to the transmitter where it will be dissipated as heat in the final amplifiers. This is not good, especially with solid-state gear. For receivers, the same thing happens, but the energy lost is so miniscule as to not be dangerous in any way. However, you will lose energy from the antenna in a bad mismatch. The best way to deal with this, from a receiving point of view, is to get a good-enough match. You don't need an antenna "tuner" or complex matching device; if you have, for example, an end-fed wire, a fixed matching transformer such as those made by I.C.E. and other companies (improperly often called "magnetic longwire baluns" which is a triple misnomer), will set things up for you, gaining an s-unit and lowering the background noise level. (The latter is a whole 'nuther discussion.) For more info on random, end-fed wires, see http://www.anarc.org/naswa/badx/ante...e_antenna.html If you're using a dipole, make it a multiband "fan" or "trapped" dipole or a broadband folded dipole. Search for T2FD, TTFD or "terminated, tilted folded dipole" for more info on the latter. T2FD and other wire antenna info can be found he http://www.hard-core-dx.com/nordicdx...ire/index.html Hope this helps! P -- Eric F. Richards, "This book reads like a headache on paper." http://www.cnn.com/2001/CAREER/readi...one/index.html |
#3
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I think it depends on how far into the noise you're digging signals out of.
A few db of missmatch loss is nothing if your target is S9. A few db of loss is everything if the target is only just above your noise floor. jw milwaukee |
#4
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''Magnetic'' is appropriate, is it not?
On Tue, 30 Dec 2003 01:30:34 -0700, Eric F. Richards wrote: "Peter" wrote: Hi there, is antenna matching important for receiving as much as for transmitting. Sorry if this is a dumb question. Well it's on topic and not about the latest conspiracy theory, so it's not a dumb question. The short answer is no. The longer answer is that antenna matching with a transmitter is about energy transfer -- a mismatched load will cause power to be reflected back to the transmitter where it will be dissipated as heat in the final amplifiers. This is not good, especially with solid-state gear. For receivers, the same thing happens, but the energy lost is so miniscule as to not be dangerous in any way. However, you will lose energy from the antenna in a bad mismatch. The best way to deal with this, from a receiving point of view, is to get a good-enough match. You don't need an antenna "tuner" or complex matching device; if you have, for example, an end-fed wire, a fixed matching transformer such as those made by I.C.E. and other companies (improperly often called "magnetic longwire baluns" which is a triple misnomer), will set things up for you, gaining an s-unit and lowering the background noise level. (The latter is a whole 'nuther discussion.) For more info on random, end-fed wires, see http://www.anarc.org/naswa/badx/ante...e_antenna.html If you're using a dipole, make it a multiband "fan" or "trapped" dipole or a broadband folded dipole. Search for T2FD, TTFD or "terminated, tilted folded dipole" for more info on the latter. T2FD and other wire antenna info can be found he http://www.hard-core-dx.com/nordicdx...ire/index.html Hope this helps! P |
#5
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David wrote:
''Magnetic'' is appropriate, is it not? Try electromagnetic. Unless, of course, you can pick up iron filings with one... -- Eric F. Richards "The weird part is that I can feel productive even when I'm doomed." - Dilbert |
#6
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PV,
Antenna to Transmitter "Impedance Matching" for the best (optimum) Power transfer for Transmitting is not an important objective of a SWL who is trying to get the MOST out of his/her Antenna and Radio for the best (optimum) Radio Reception. BUT - Antenna {PRE} Tuning is a Very Desirable Objective for a SWL. Build your own Antenna Matching Device {Coupler} for Improved 'portable' SW Radio [Sony 2010] Reception - by Robert Colegrove http://www.hard-core-dx.com/nordicdx...l/2010ant.html Coupler Diagram: http://www.hard-core-dx.com/nordicdx.../coupdiag.html NOTE: Adding a Variable "Tuning" Capacitor across [J1] and [P2] can turn this Coupler in to a good Antenna Pre-Selector. iane ~ RHF .. .. "Build your own Antenna-to-Radio "Matching" Device {Coupler}" http://groups.yahoo.com/group/SWL-AM...na/message/442 .. .. = = = "Peter" = = = wrote in message ble.rogers.com... Hi there, is antenna matching important for receiving as much as for transmitting. Sorry if this is a dumb question. P .. |
#7
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It does a lot thanks
"Eric F. Richards" wrote in message ... "Peter" wrote: Hi there, is antenna matching important for receiving as much as for transmitting. Sorry if this is a dumb question. Well it's on topic and not about the latest conspiracy theory, so it's not a dumb question. The short answer is no. The longer answer is that antenna matching with a transmitter is about energy transfer -- a mismatched load will cause power to be reflected back to the transmitter where it will be dissipated as heat in the final amplifiers. This is not good, especially with solid-state gear. For receivers, the same thing happens, but the energy lost is so miniscule as to not be dangerous in any way. However, you will lose energy from the antenna in a bad mismatch. The best way to deal with this, from a receiving point of view, is to get a good-enough match. You don't need an antenna "tuner" or complex matching device; if you have, for example, an end-fed wire, a fixed matching transformer such as those made by I.C.E. and other companies (improperly often called "magnetic longwire baluns" which is a triple misnomer), will set things up for you, gaining an s-unit and lowering the background noise level. (The latter is a whole 'nuther discussion.) For more info on random, end-fed wires, see http://www.anarc.org/naswa/badx/ante...e_antenna.html If you're using a dipole, make it a multiband "fan" or "trapped" dipole or a broadband folded dipole. Search for T2FD, TTFD or "terminated, tilted folded dipole" for more info on the latter. T2FD and other wire antenna info can be found he http://www.hard-core-dx.com/nordicdx...ire/index.html Hope this helps! P -- Eric F. Richards, "This book reads like a headache on paper." http://www.cnn.com/2001/CAREER/readi...one/index.html |
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