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Designing an antenna for the 5000m band
On Mon, 16 Feb 2009 22:22:20 -0600, Frnak McKenney wrote:
Back in December I posted a question about ways to receive LF/VLF radio signals. Based on the suggestions made by a number of people here I decided to use my existing Heathkit Mohican receiver and add this upconverter kit from Jackson Harbor: http://jacksonharbor.home.att.net/lfconv.htm The kit arrived and was half assembled before I turned on the Mohican, its first power-up in some years; the horrible squeal that erupted from the speaker put a bit of a damper on things. It now appears that replacing the two output transistors (Germanium, no less!) with NTE102As from Mouser will fix that, so I'm thinking about an antenna that might be a little more snesitive to LF signals than the Mohican's built-in whip. Along those lines, I have a couple of (what I hope are) simple questions that I'm hoping someone can help me get started with. First, the need for impedance matching between an antenna and a receiver. My understanding is that a resonant halfwave dipole will have an impedance around 73 Ohms; unfortunately, unless I can obtain research funding from the just-passed Congressional Economic Stimulus bill I'm going to have trouble paying for 2.5km of copper wire, some towers, a crateload or two of porcelain insulators,and the land to build it on. (Hey, I promise to dump it back into the economy ASAP. Really! grin!) So any non-loop antenna I can construct will necessarily be a "short wire" or "electrically small" antenna (two useful search terms). But how does one go about calculating the impedance of a coat hanger or an extension cord ("short piece of wire")? I've done Google seaarches and read what seemed like the relevant sections of the 2004 ARRL Radio Handbook and their Antenna Book; unfortunately, most authors restrict their discussion to quarter- wave or longer antennae. Any starting points, hints, or references on impedance calculations for less-than-1/10-wavelength antennas will be appreciated. My other question has to do with how to interpret signal strength. The first "standard reference" transmitter I'll be attempting to receive will be WWVB out of Fort Collins, Colorado (60kHz/5000m). Per the NIST documentation at: NIST Special Publication 250-67: NIST Time and Frequency Radio Stations: WWV, WWVH, and WWVB http://ts.nist.gov/MeasurementServices/Calibrations/ Upload/SP250-67.pdf figure 4.5 seems to say that I could reasonably expect to see a signal of at least 100uV/m. Does this mean that I should expect to see 100uV from any one-meter hunk of wire strung out horizontally in the optimum direction? Or is there something more subtle going on I need to be aware of? Why do you want a good impedance match? Why don't you want to use a loop antenna? At 5000m, atmospheric noise is very strong -- it would certainly overwhelm any thermal noise that you'd receive if you did make a 1/2 wave dipole (don't forget that your towers need to be at least 2500m tall to get close to the ideal). Getting an appropriate impedance match is mostly about maximizing your signal compared with your receiver's internal noise; the strong atmospheric noise makes this less necessary. This atmospheric noise also makes really efficient receiving antennas rather unimportant. You want a good fraction of a wavelength for _transmitting_, but it really doesn't make much difference for _receiving_. The two common receiving antennas that I know of at that sort of frequency are tuned loops and capacitive whips. A loop can be fairly small -- my understanding (which I've never tested, YMMV) is that one square meter is plenty. Loops are nice because you can tune them, so they give you some additional selectivity on your receiver front end. You can impedance match the loop to your receiver, but most of the impedance your receiver sees will come from the wire in the loop, not the radiation resistance of the loop. Loops are also somewhat directive, which helps to reduce the total static received, and if done correctly (google "shielded loop") they can be arranged to reject sky waves (I _think_ by polarization, but I'm not sure). A capacitive whip is just a 1m long wire whip (like a coat hanger or welding rod) feeding some high impedance amplifier like a JFET (or a toob, if you want to be picturesque). Put the active element right at the base of the wire for best signal. It's inherently wide band, and hard to keep it from being so, so if you have some local interference it'll kill your signal (my first try at these didn't work in my shop because of a nearby electric fence transformer, but it worked fine at the end-user's more-urban location). -- http://www.wescottdesign.com |
#12
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Designing an antenna for the 5000m band
On Feb 16, 11:22*pm, Frnak McKenney
wrote: Back in December I posted a question about ways to receive LF/VLF radio signals. *Based on the suggestions made by a number of people here I decided to use my existing Heathkit Mohican receiver and add this upconverter kit from Jackson Harbor: *http://jacksonharbor.home.att.net/lfconv.htm The kit arrived and was half assembled before I turned on the Mohican, its first power-up in some years; the horrible squeal that erupted from the speaker put a bit of a damper on things. *It now appears that replacing the two output transistors (Germanium, no less!) *with NTE102As from Mouser will fix that, so I'm thinking about an antenna that might be a little more snesitive to LF signals than the Mohican's built-in whip. Along those lines, I have a couple of (what I hope are) simple questions that I'm hoping someone can help me get started with. First, the need for impedance matching between an antenna and a receiver. *My understanding is that a resonant halfwave dipole will have an impedance around 73 Ohms; unfortunately, unless I can obtain research funding from the just-passed Congressional Economic Stimulus bill I'm going to have trouble paying for 2.5km of copper wire, some towers, a crateload or two of porcelain insulators,and the land to build it on. *(Hey, I promise to dump it back into the economy ASAP. *Really! *grin!) So any non-loop antenna I can construct will necessarily be a "short wire" or "electrically small" antenna (two useful search terms). But how does one go about calculating the impedance of a coat hanger or an extension cord ("short piece of wire")? I've done Google seaarches and read what seemed like the relevant sections of the 2004 ARRL Radio Handbook and their Antenna Book; unfortunately, most authors restrict their discussion to quarter- wave or longer antennae. *Any starting points, hints, or references on impedance calculations for less-than-1/10-wavelength antennas will be appreciated. My other question has to do with how to interpret signal strength. The first "standard reference" transmitter I'll be attempting to receive will be WWVB out of Fort Collins, Colorado (60kHz/5000m). Per the NIST documentation at: * NIST Special Publication 250-67: NIST Time and Frequency Radio * * * * * * Stations: WWV, WWVH, and WWVB *http://ts.nist.gov/MeasurementServices/Calibrations/ * * * * * * Upload/SP250-67.pdf figure 4.5 seems to say that I could reasonably expect to see a signal of at least 100uV/m. *Does this mean that I should expect to see 100uV from any one-meter hunk of wire strung out horizontally in the optimum direction? Or is there something more subtle going on I need to be aware of? Frank McKenney A field strength measured in Volts/meter is just that, but the problem getting the energy out of the air and into a receiver. A short linear antenna has a very low radiation resistance ( 1 ohm) which is a poor match to a practical transmission line, whose characteristic impedance is typically 1000's of times larger. The radiation resistance of an antenna is the component of its complex impedance that is associated with the power captured. Poor impedance matching is equivalent to low energy efficiency, in this case very low. One solution is to use a small circular loop antenna whose low radiation resistance can be increased by adding turns. Balanis (Antenna Theory Analysis & Design (1997), p.209) gives a formula for the radiation resistance of a loop smaller than 1/25 wavelength: R = 20 * pi^2 * (C/L)^4 * N^2 ohms where C is the circumference of the loop, L is the wavelength and N is the number of turns. Better still is to use a ferrite loop antenna. You may be able to get one out of an old AM radio and adapt it to your receiver. The resulting formula is identical to the above, multiplied by the relative permeability of the core, u (SQUARED !), so you can use a very small-diameter loop and/or fewer turns, getting improved selectivity and sensitivity (i.e. high Q) in a tuned circuit: R = 20 * pi^2 * (C/L)^4 * N^2 * u^2 ohms -- Joe |
#13
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Designing an antenna for the 5000m band
"Phil Allison" wrote in message ... "Frnak McKenney" http://ts.nist.gov/MeasurementServic...d/SP250-67.pdf ** Just how big is this file - eh ?? Why did you limit replies to ONE newsgroup while posting to TWO ??? What sort to total ****ING ASSHOLE are you ???? You ****ing ASININE YANK ****- head. ..... Phil Uh-oh! Looks like somebody isn't getting enough fiber! |
#14
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Designing an antenna for the 5000m band
On Mon, 16 Feb 2009 22:22:20 -0600, Frnak McKenney wrote:
Back in December I posted a question about ways to receive LF/VLF radio signals. Based on the suggestions made by a number of people here I decided to use my existing Heathkit Mohican receiver and add this upconverter kit from Jackson Harbor: http://jacksonharbor.home.att.net/lfconv.htm The kit arrived and was half assembled before I turned on the Mohican, its first power-up in some years; the horrible squeal that erupted from the speaker put a bit of a damper on things. It now appears that replacing the two output transistors (Germanium, no less!) with NTE102As from Mouser will fix that, so I'm thinking about an antenna that might be a little more snesitive to LF signals than the Mohican's built-in whip. Along those lines, I have a couple of (what I hope are) simple questions that I'm hoping someone can help me get started with. First, the need for impedance matching between an antenna and a receiver. My understanding is that a resonant halfwave dipole will have an impedance around 73 Ohms; unfortunately, unless I can obtain research funding from the just-passed Congressional Economic Stimulus bill I'm going to have trouble paying for 2.5km of copper wire, some towers, a crateload or two of porcelain insulators,and the land to build it on. (Hey, I promise to dump it back into the economy ASAP. Really! grin!) So any non-loop antenna I can construct will necessarily be a "short wire" or "electrically small" antenna (two useful search terms). But how does one go about calculating the impedance of a coat hanger or an extension cord ("short piece of wire")? I've done Google seaarches and read what seemed like the relevant sections of the 2004 ARRL Radio Handbook and their Antenna Book; unfortunately, most authors restrict their discussion to quarter- wave or longer antennae. Any starting points, hints, or references on impedance calculations for less-than-1/10-wavelength antennas will be appreciated. My other question has to do with how to interpret signal strength. The first "standard reference" transmitter I'll be attempting to receive will be WWVB out of Fort Collins, Colorado (60kHz/5000m). Per the NIST documentation at: NIST Special Publication 250-67: NIST Time and Frequency Radio Stations: WWV, WWVH, and WWVB http://ts.nist.gov/MeasurementServices/Calibrations/ Upload/SP250-67.pdf figure 4.5 seems to say that I could reasonably expect to see a signal of at least 100uV/m. Does this mean that I should expect to see 100uV from any one-meter hunk of wire strung out horizontally in the optimum direction? Or is there something more subtle going on I need to be aware of? This may be a duplicate answer: I _know_ I wrote one, but it seems to have fallen into the bit-bucket. In short: For receiving you don't need to couple well enough to the ether to overwhelm the receiver's noise with the Faintest Possible Signal. You only need to overwhelm the receiver's noise with atmospheric noise. Given the amount of atmospheric noise at 60kHz, that ain't hard. When you get to the point where you hook up the antenna to the rig and you heard static over the noise of the receiver, you know your antenna is good enough. (Transmitting is a different story, but try transmitting at 60kHz and after the FCC gets done with you antenna size will be the least of your worries.) Whazza matta widda loop? They work fine, they provide some welcome selectivity (well, at 60kHz one may provide _too much_ selectivity), they're easy to construct, they're reputed to reject sky waves -- what more could you want? If you don't want to use a loop, the last time I did anything at MF a short (1m) whip going to a JFET source follower was considered the bee's knees to solve this sort of problem. The whip will pick up atmospheric noise just as well as it'll pick up the intended signal, the JFET will impedance match from that low-capacity whip to your receiver input (I assume, I don't know what the nominal input impedance of your rig is), and all will be well. -- http://www.wescottdesign.com |
#15
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Designing an antenna for the 5000m band
On Feb 18, 8:05*am, "Sal M. Onella"
wrote: "Phil Allison" wrote in message ... "Frnak McKenney" *http://ts.nist.gov/MeasurementServic...d/SP250-67.pdf ** Just how big is this file * * - *eh *?? Why did you limit replies to *ONE *newsgroup while posting *to TWO * ??? What sort to total *****ING *ASSHOLE *are you * ???? You ****ing *ASININE *YANK *****- head. ..... * Phil Uh-oh! *Looks like somebody isn't getting enough fiber! Someone woke up on the wrong side of NOBODY again.... |
#16
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Designing an antenna for the 5000m band
On Feb 16, 11:22*pm, Frnak McKenney
wrote: Back in December I posted a question about ways to receive LF/VLF radio signals. *Based on the suggestions made by a number of people here I decided to use my existing Heathkit Mohican receiver and add this upconverter kit from Jackson Harbor: *http://jacksonharbor.home.att.net/lfconv.htm The kit arrived and was half assembled before I turned on the Mohican, its first power-up in some years; the horrible squeal that erupted from the speaker put a bit of a damper on things. *It now appears that replacing the two output transistors (Germanium, no less!) *with NTE102As from Mouser will fix that, so I'm thinking about an antenna that might be a little more snesitive to LF signals than the Mohican's built-in whip. Along those lines, I have a couple of (what I hope are) simple questions that I'm hoping someone can help me get started with. First, the need for impedance matching between an antenna and a receiver. *My understanding is that a resonant halfwave dipole will have an impedance around 73 Ohms; unfortunately, unless I can obtain research funding from the just-passed Congressional Economic Stimulus bill I'm going to have trouble paying for 2.5km of copper wire, some towers, a crateload or two of porcelain insulators,and the land to build it on. *(Hey, I promise to dump it back into the economy ASAP. *Really! *grin!) So any non-loop antenna I can construct will necessarily be a "short wire" or "electrically small" antenna (two useful search terms). But how does one go about calculating the impedance of a coat hanger or an extension cord ("short piece of wire")? I've done Google seaarches and read what seemed like the relevant sections of the 2004 ARRL Radio Handbook and their Antenna Book; unfortunately, most authors restrict their discussion to quarter- wave or longer antennae. *Any starting points, hints, or references on impedance calculations for less-than-1/10-wavelength antennas will be appreciated. My other question has to do with how to interpret signal strength. The first "standard reference" transmitter I'll be attempting to receive will be WWVB out of Fort Collins, Colorado (60kHz/5000m). Per the NIST documentation at: * NIST Special Publication 250-67: NIST Time and Frequency Radio * * * * * * Stations: WWV, WWVH, and WWVB *http://ts.nist.gov/MeasurementServices/Calibrations/ * * * * * * Upload/SP250-67.pdf figure 4.5 seems to say that I could reasonably expect to see a signal of at least 100uV/m. *Does this mean that I should expect to see 100uV from any one-meter hunk of wire strung out horizontally in the optimum direction? Or is there something more subtle going on I need to be aware of? Frank McKenney A field strength measured in 100 uV/meter is just that, but the problem getting the energy out of the air and into a receiver. A short linear antenna has a very low radiation resistance ( 1 ohm) which is a poor match to a practical transmission line, whose characteristic impedance is typically 1000's of times larger. The radiation resistance of an antenna is the component of its complex impedance that is associated with the power captured. Balanis (Antenna Theory Analysis & Design (1997), p.137) gives a formula for the radiation resistance of a short dipole: R = 80 * pi^2 * (W/L)^2 ohms where W is the length of the antenna and L is the wavelength. The value for a monopole is roughly half as much again. Why do you request a non-loop antenna? A small circular loop antenna also has a low radiation resistance but it can be increased by adding turns. Balanis (p.209) gives a formula for the radiation resistance of a small loop: R = 20 * pi^2 * (C/L)^4 * N^2 ohms where C is the circumference of the loop, L is the wavelength and N is the number of turns. Better still is to use a ferrite loop antenna. You may be able to get one out of an old AM radio and adapt it to your receiver. The resulting formula is identical to the above, multiplied by the relative permeability of the core, u (SQUARED !), so you can use a very small-diameter loop and/or fewer turns, getting improved selectivity and sensitivity (i.e. high Q) in a tuned circuit: R = 20 * pi^2 * (C/L)^4 * N^2 * u^2 ohms -- Joe |
#17
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Designing an antenna for the 5000m band
Richard,
Thank you for posting back. On Mon, 16 Feb 2009 23:07:37 -0800, Richard Clark wrote: On Mon, 16 Feb 2009 22:22:20 -0600, Frnak McKenney wrote: First, the need for impedance matching between an antenna and a receiver. --snip complaint about the size/cost of 60kHz h-w diploes grin!-- So any non-loop antenna I can construct will necessarily be a "short wire" or "electrically small" antenna (two useful search terms). But how does one go about calculating the impedance of a coat hanger or an extension cord ("short piece of wire")? One doesn't try. So Yoda was right: "Do, or do not. There is no 'try'." grin! What has puzzled me is that I have run across designs that use (e.g.) a JFET isolation amplifier hooked to a whip or hunk-o-wire with the statement (or implication) that this is done to ",atch the antenna's impedance". So I;ve been trying to figure out how to calculate/estimate what it would be, without much success. The simple solution is the conventional one - you use a tuner. The tuner provides the matching (providing it has sufficient inductance and capacitance - you will have to investigate designs) and adjacent signal rejection (which could seriously de-sense your received signals). I imagine that the inductance of a 6' extension cord (not plugged in, just dangling from a planter hook grin!) is down in the uH-or-less range, which would mean that most of the "tuning" inductance would have to be supplied to achieve 60kHz. I have this image of a big (tens of mH) inductor in series with a moderate capacitor and my (electrically) short wire; all of the surrounding EM sets the electroncs in the wire to dancing, but the series RC blocks those which are wiggling "off-key" (e.g. not dancing at the "proper" rate of 60kHz). Your antenna doesn't need to be very big, but it might help to have it very remote, if there are noise sources nearby (like motors, aquarium heaters, bottle style TVs, ...); and the line sufficiently choked. A good ground too, tying into the service ground through a separate wire to reduce coupling of noise from shared grounds. Well, there's no question that I have EM in the area. I hooked my DVM -- set to ACV -- between the radiator and my 6' extension cord; would you believe 8-10V??!! Not much current, though: feed it through a 1k resistor and measure the voltage across it, suddenly it's down in the mV range. grin! ... This last may introduce a ground loop if your Mohican is so vintage as to have had relaxed design standards. A little research online reveals it is battery operable. You may want to fully exercise that option. The Mohican came with two 12V power "modules" which plug into the back of the unit. The AC power module has a transformer with a 12V-12V center-tapped secondary, which is good, but then they run the line voltage out of the module and down into the receiver's volume control's on/off switch. The module's 12V power and 120V switching connections are done through a 9-pin tube socket with mating connector/cable; remember those? grin! 73's Thanks for the hepl. Frank -- There is one thing even more vital to science than intelligent methods; and that is, the sincere desire to find out the truth, whatever that may be. -- Charles Sanders Pierce -- Frank McKenney, McKenney Associates Richmond, Virginia / (804) 320-4887 Munged E-mail: frank uscore mckenney ayut mined spring dawt cahm (y'all) |
#18
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Designing an antenna for the 5000m band
On Tue, 17 Feb 2009 13:56:38 GMT, GregS wrote:
In article , Frnak McKenney wrote: Back in December I posted a question about ways to receive LF/VLF radio signals. --snip-- ... I'm thinking about an antenna that might be a little more snesitive to LF signals than the Mohican's built-in whip. http://www.frontiernet.net/~jadale/Loop.htm Thanks for the link. Firefox claims I visited it recently, but I apparently forgot to save it into my "VLF Antenna" folder. It's there _now_! grin! Frank -- "Wisdom lies in taking everything with good humor and a grain of salt." -- George Santayana -- Frank McKenney, McKenney Associates Richmond, Virginia / (804) 320-4887 Munged E-mail: frank uscore mckenney ayut mined spring dawt cahm (y'all) |
#19
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Designing an antenna for the 5000m band
Jeff,
Thanks for the reply. On Tue, 17 Feb 2009 08:36:23 -0800, Jeff Liebermann wrote: On Mon, 16 Feb 2009 22:22:20 -0600, Frnak McKenney wrote: So any non-loop antenna I can construct will necessarily be a "short wire" or "electrically small" antenna (two useful search terms). But how does one go about calculating the impedance of a coat hanger or an extension cord ("short piece of wire")? Antennas can be modeled by various NEC based programs. For example: http://home.ict.nl/~arivoors/ http://www.eznec.com http://www.nittany-scientific.com Note that the common "atomic clock" gets its time from WWVB at 60KHz (about 5000 meters) using a tiny loop antenna. Huge antennas are not required for many application. http://www.mas-oy.com/data/MAS_docu_AR.htm http://www.leapsecond.com/pages/sony-wwvb/ That's what I keep reading; any caution you hear coming from me is based on years spent in close association with Murphy. grin! I'm a long-time devotee of the Divide'n'Conquer(tm) school of analysis and troubleshooting. This only works well when one is familiar with the appropriate problem-partitioning tools and has experience using them; as it is, I'm trying to acquire the knowledge that will let me know why things didn't work when they don't work as expected. grin! Also, search Google for LOWFER. Thanks. I did see the phrase, but forgot to write it down; after some hours searching the 'Web and reading it all seems to run together. grin! Frank -- "When the government fears the people, there is liberty. When the people fear the government, there is tyranny." -- Thomas Jefferson -- Frank McKenney, McKenney Associates Richmond, Virginia / (804) 320-4887 Munged E-mail: frank uscore mckenney ayut mined spring dawt cahm (y'all) |
#20
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Designing an antenna for the 5000m band
Tim,
Thanks for the response. On Tue, 17 Feb 2009 11:02:42 -0600, Tim Wescott wrote: On Mon, 16 Feb 2009 22:22:20 -0600, Frnak McKenney wrote: Back in December I posted a question about ways to receive LF/VLF radio signals. --snip-- First, the need for impedance matching between an antenna and a receiver. --snip-- So any non-loop antenna I can construct will necessarily be a "short wire" or "electrically small" antenna (two useful search terms). But how does one go about calculating the impedance of a coat hanger or an extension cord ("short piece of wire")? --snip-- Why do you want a good impedance match? Because I'm trying to snatch a signal that I have no experience with "out of the aether", a signal that has to somehow excite an antenna, feed into an upconverter, arrive at my receiver, and produce some specific identifying evidence that I'm detecting the signal I hope it will rather than (say) reporting that my neighbor is using his electric razor. grin! Each of these pieces (except perhaps the Mohican) are untested (by me), and I don't have any tools that will help me easily distinguish between (say) a bad upconverter, a poor antenna, or excessive noise. Like many such situations, I'll know if I _succeed_, but if I don't there won't be any clear indicators to help me figure out _which_ piece of the puzzle isn't fitting properly. In short, anything that sounds like it might affect my results is of interest to me. Why don't you want to use a loop antenna? It's a question of time and effort: it looks like it will take me less of each to test the "wire" first. If it succeeds, I'm done; if not, I can start experimenting with loops. Which is, of course, a variant on one of my favorite puzzles: How do you allocate your resources when you don't yet know what you're doin... er, "under conditions of less-than-perfect information"? grin! At 5000m, atmospheric noise is very strong -- it would certainly overwhelm any thermal noise that you'd receive if you did make a 1/2 wave dipole (don't forget that your towers need to be at least 2500m tall to get close to the ideal). Getting an appropriate impedance match is mostly about maximizing your signal compared with your receiver's internal noise; the strong atmospheric noise makes this less necessary. Yeah. All that, plus the funding. But mostly the funding. grin! This atmospheric noise also makes really efficient receiving antennas rather unimportant. You want a good fraction of a wavelength for _transmitting_, but it really doesn't make much difference for _receiving_. Which may well be true, but it seems puzzling. Why would it not be important to deliver as much of the induced electron movement to a receiver as possible? The two common receiving antennas that I know of at that sort of frequency are tuned loops and capacitive whips. A loop can be fairly small -- my understanding (which I've never tested, YMMV) is that one square meter is plenty. Loops are nice because you can tune them, so they give you some additional selectivity on your receiver front end. You can impedance match the loop to your receiver, but most of the impedance your receiver sees will come from the wire in the loop, not the radiation resistance of the loop. Talking about "radiation resistance" in a receiver antenna also feels a bit odd. ... Loops are also somewhat directive, which helps to reduce the total static received, and if done correctly (google "shielded loop") they can be arranged to reject sky waves (I _think_ by polarization, but I'm not sure). Yes. I'm reading up on loops so I have an alternative available in caseXXXXXXX_when_ something goes wrong. A capacitive whip is just a 1m long wire whip (like a coat hanger or welding rod) feeding some high impedance amplifier like a JFET (or a toob, if you want to be picturesque). Put the active element right at the base of the wire for best signal. It's inherently wide band, and hard to keep it from being so, so if you have some local interference it'll kill your signal This is the direction I'm starting in. ... (my first try at these didn't work in my shop because of a nearby electric fence transformer, but it worked fine at the end-user's more-urban location). Gack! I don't suppose it used an old Model-T spark coil, or a buzzer-and transformer equivalent? I remember in my youth (Dirt(tm) _had_ been invented, but it was still considered cutting-edge technology grin!) just how badly one could mess up AM BCB reception with a string of those Christmas tree bulbs with built-in bimetallic-switch flashers. Frank -- You'll never learn to do anything well until you're willing to accept that you'll do it badly at first. --Anonymous -- Frank McKenney, McKenney Associates Richmond, Virginia / (804) 320-4887 Munged E-mail: frank uscore mckenney ayut mined spring dawt cahm (y'all) |
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