开云体育

Hello from your friendly neighborhood moderator. If you see spam here, or something you think feel is spam or so far off topic that it does not belong here, please email me at [email protected] and include a link to the message on the website. Please do NOT mark as spam, especially don't mark it as spam in your email program. Due to the measures taken by many/most ISPs, groups,io will boot you from any group that you mark as spam. Even if your email program puts it in your spam folder without any action by you, if you allow it to delete it without marking it "not spam", 开云体育 will boot you from the group. No actions by me. It is not my choice that such a nuclear option be used. However, so many people sign up for a list then either forget the did, or decide they want off but somehow find it "easier" to start marking the messages as spam... or lazily allow their email program or provider to mark as spam and don't bother correcting it. Also, while we're talking about this sort of thing, I'm not your momma. If you want one of your own messages deleted, if you want to stop following a topic, if you want to change your email preferences in some way, please do so yourself. 99.9% of you seem to be self-sufficient, but I moderate a couple dozen groups with tens of thousands of members. Thank you, and stay healthy. -- Steve Greenfield AE7HD

When something is posted in Files, the only way to view it is to download it. If you have not put a description, if I have to download a file to look at it to tell what it is, I'm deleting it. There are too many JPGs in there with only a date code as a name with no or only a cryptic description. I'm deleting them. Think about someone going into Files or Photos a few years from now, not having your emails discussing it in mind. Will they know what it is based on the file name and description? Is it useful for them? Files and photos not in folders are a bit like going to a common meeting space, throwing pictures and little bits of stuff everywhere, then just leaving it for someone else to figure out and clean up. It is rude and inconsiderate. If you only need to share a file temporarily, consider posting it on a file sharing site and putting the link in your message. Thank you, -- Steve Greenfield AE7HD

Wow! Woke up a few minutes ago and just discovered the loop antennas group had vanished! Fortunately, it is still here and it looks like we have a clean slate. 73, 'Bear' NH7SR

Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the loopantennas group. File : /loopcalc.exe Uploaded by : qrpbear <qrpbear@...> Description : Excellent Windows-based loop calculator. Gives many important parameters. You can access this file at the URL http://groups.yahoo.com/group/loopantennas/files/loopcalc.exe To learn more about file sharing for your group, please visit http://help.yahoo.com/help/us/groups/files Regards, qrpbear <qrpbear@...>

http://www.groups.yahoo.com/group/radiodxworld/ http://www.groups.yahoo.com/group/gccloopantennadesign/ < ITS HERE! and will be listed since its a popular GCC group. Oh, Dude? You know thats my group? electronicdx.

Just uploaded the KI6GD Loop Calculator to the Files Section. Something that I have been meaning to do for a long time. For those unfamiliar with the program, it allows you to enter a given loop circumference and operating frequency (as well as other parameters). It will then calculate the Q, efficiency, bandwidth, voltage across the resonating capacitor, ohmic loss, radiation resistance, etc, etc. Really great for doing "what if" calculations. It does square, octagonal and circular form loops... but it doesn't do multi-turn loops. I'm still looking for a simple Windows-based calculator for multi-turn loop calculation. Enjoy! 73, 'Bear' NH7SR

RadioDXWorld says no such group. So you renamed it? I'd thought you killed it after that email you sent today, and then Yahoogroups said no such group. I thought we'd lost all those excellent links and the wonderful archives. I'm still confused about what the fuss was, this time and the time before. I don't see any reason to take this one down. Please place a link (if you wish) to your loop list in the Links section. I have this list set public, anyone can join but all new members are moderated. I'm pretty quick about unmoderating once someone shows they are a real person. Steve

Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the loopantennas group. File : /ModeratorFiles/AboutLoopAntennas.txt Uploaded by : alienrelics <alienrelics@...> Description : About LoopAntennas list - not the same as the old LoopAntennas list. You can access this file at the URL http://groups.yahoo.com/group/loopantennas/files/ModeratorFiles/AboutLoopAntennas.txt To learn more about file sharing for your group, please visit http://help.yahoo.com/help/us/groups/files Regards, alienrelics <alienrelics@...>

hello everyone Scott

Some of you were set to No Email. I changed you to Special Notices so everyone would get this. Please, feel free to change your settings back to No Email. I'm the only one who can send out as a Special Notice, and I don't typically use it much. Here's the skinny- I'm not the moderator of the old LoopAntennas. I'm the moderator of the new LoopAntennas. What happened: I got ElectronicDX's special notice earlier today, threatening to shut down the list. I sent a reply, it bounced, I tried to go to the list, Yahoogroups said no such list! So after thinking about it for a few hours, I started up a Group as LoopAntennas. I figured I'll start collecting links and files and information where I don't have to worry about it getting deleted. I'm list-owner or moderator of 15 lists, with 5,664 members between them. Like those, I've set this one so new members are moderated. Post once (maybe twice, I do have a life ;')) and I'll change you to non-moderated. If you spot a spam link or file or photo, email me off list and I'll remove it. Turns out ElectronicDX just changed the names of all his groups, adding "gcc" to the title. So it's gccloopantennas, etc. If you were a member of his lists before, you are still a member. All the files and links and archives are still intact over there. However, that doesn't change anything I said above. I hope no one leaves gccloopantennas for this one, but I do hope people join this list in addition to that one. Post good links and files, please be specific in your description. I reserve the right to delete a link or file if there is no description, and I will probably make some folders and move them around a bit as soon as there is enough to make that worth doing. Check my other lists to see what I do with files and links areas: http://groups.yahoo.com/group/Homebrew_PCBs http://groups.yahoo.com/group/mad_scientist http://groups.yahoo.com/group/nwpropmasters http://groups.yahoo.com/group/Electronics_101 Thanks from the list-owner of the new loopantennas list. Steve Greenfield aka Alien Steve aka Polymorph

Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the loopantennas group. File : /ModeratorFiles/June072004IMfromElectronicDX.txt Uploaded by : alienrelics <alienrelics@...> Description : Afternoon of June 7th, I was in an IM conversation with ElectronicDX. I'm AlienRelics and my name is Steve Greenfield, and I'm list-owner of the new LoopAntennas list. You can access this file at the URL http://groups.yahoo.com/group/loopantennas/files/ModeratorFiles/June072004IMfromElectronicDX.txt To learn more about file sharing for your group, please visit http://help.yahoo.com/help/us/groups/files Regards, alienrelics <alienrelics@...> .

Hello, This email message is a notification to let you know that a file has been uploaded to the Files area of the loopantennas group. File : /Links.txt Uploaded by : alienrelics <alienrelics@...> Description : Until I get a chance to sort them out and put them in the Links folder, here are all the links I had saved. You can access this file at the URL http://groups.yahoo.com/group/loopantennas/files/Links.txt To learn more about file sharing for your group, please visit http://help.yahoo.com/help/us/groups/files Regards, alienrelics <alienrelics@...>

Hi, Thanks to whoever initiated the move to start over. I value the discussions regarding loop antenna design, fabrication and use that take place daily on this list and resent the actions of the previous list moderator / owner to transfer my subscription without discussion or consent to another group not at all to my liking. Please do not hesitate to contact me off list for any additional help or support that may be required to get this group going again. Thanks and regards, David Kent / k4uja

It's too bad things busted up into two groups, but I choose to stay with this one and leave the other. Hopefully this will grow to becoming the excellent group that it was in the past. Please don't mess with the colors. Green on blue on red on yellow on black is a bit hard to take. Leave it like it is, please. Thanks. Al KA5JGV

A little something to start off some discussion here... Back in 1993 Rod Newkirk, W9BRD, published an article entitled "Honey I Shrunk the Loop" in QST magazine (July, 1993). For those without access to the article, it described a multi-turn loop antenna with a resonating capacitor inserted at the center of each turn. The benefits of doing so were supposedly to reduce the voltage across each of the capacitors and to make it easier to match to 50 ohm coax. It seems to me that the same principle could be used to construct a "bandpass" loop that would not require retuning within a certain band of frequencies much wider than a single-tuned loop. Have any of you folks built one of these? If so, how well did it perform for you? 73, 'Bear' NH7SR

Another thing that keeps floating up from the depths of my subconscious... How would a multi-turn loop having space between turns a significant percentage of the loop diameter work relative to one that has closer spacing? For instance, a 2-turn 36" diameter loop with 12" between turns. My instincts tell me that there would be an increase in the physical capture area of the loop due to its taking on a more 3-D profile. This would lead to higher performance than a close-spaced loop winding. How much increase in performance? Would there be an optimal spacing? What about spacing equal to loop diameter? Hmmm... obviously I need more copper... a LOT more! Uhh... got any spare capacitors? 73, 'Bear' NH7SR

While walking home from the bus stop yesterday I encountered an HP printer that someone had thrown away. Naturally I snagged that puppy! I've been thinking about using the stepper motors out of it for remote tuning drive for loop capacitors. Have any of you folks tried steppers from old printers? Anything special I should look out for? 73, 'Bear' NH7SR

Hello All: Over the last couple of years I have done extensive searching for both theory and practice with regard to loop antennas, and here is what I have found: 1. Most of the theory is way over my head, since the last calculus class I took was over 30 years ago. 2. Most practice sites explain very well how to *make* things, but not much time is spent on *how it works*. 3. There is not much in between, some exceptions are Ian Purdie's Austrailian site and Rod Elliot's Elliot Sound Products (ESP) site. Both have excellent tutorials on them. A few ham sites have good explanations of the connection between theory and practice. So, what I see is a big blank area in between, and I find myself going back and forth between the two without a lot of insight being gained in the process. For example, there are many sites with formulas for inductance of solonoid, spiderweb, rook, conical, helical, etc coils, but very little on distributed capacitance and how it varies with spacing and wire sizes (unless you want to flagellate yourself with a treatise on Maxwell's equations). I would love to use a spreadsheet that included the inductive, capacitive and pure resistive components of everything from a long straight wire to coils (as well as loops) as well as most of the common shapes (circular, square, polygonal). If I had all the formulas (in an algebraic form, not in differential calculus form) I would even be willing to put the spreadsheet together and post it to the group. I am using OpenOffice as my office suite, so I can write it out in Excel format. A good starting place is the Dr. Coyle spreadsheet, which I use all the time. It has formulas for both solonoid and spiderweb designs, as well as input for capacitance and it will calculate the resonant frequency for a given inductance, wire size and number of turns, and gives the physical size of the coil form and length of wire needed. But I want more. The Qu would be nice, and so would the impedance (since it does calculate the reactance). I added a table of wire resistance to the spreadsheet, but at this point I am not clear on which way to calculate the Q. (I mean, wouldn't the Q tend to infinity as the resistance went to zero?) And then there is the distributed capacitance. I mean, how many Coulombs (sp) does a wire of a given diameter (at least of copper) have per unit length, given a specific voltage? And how much of a charge is induced into an adjacent wire a given length away? And (while I'm on a roll) how fast does the electrostatic charge collapse at a specific frequency and voltage? It seems to me that this information could be used to calculate the capacitive reactance, and therefore the self-resonant frequency of the coil (or loop). And couldn't one simply multiply the turns by some constant instead of integrating a complex function from one end of the coil to the other? And (Oh, my god!), none of this has taken into account permeability, reluctance, admittance, etc. for non-air-core devices. Woe is me and Oy Vey! Where do I go from here? Any help would be most appreciated. Barry

Got a strange IM from electronicdx: alienrelics: Why did you kick me off your lists? What do you mean, "put down by your members"? I don't control anyone, and I can't see anything for you to be mad about. alienrelics: What have I ever said to make you angry? electronicdx: What I mean is that they are against me in a way, but this talk is over. I will get you back in enough said. ok. :-< This is a little disturbing. "get you back"? Does anyone here personally know Adam? Steve

Just received the invitation to join this list. Pleasure to be here; thankyouverymuch. One of the loop antennas I have built was about 4 feet on a side, about 4 turns; built for listening to atmospherics, or 'spherics as I understand they are called. Worked great; had to take it well out of town, which at that time turned out to be to Coal Oil Point, CA. Did it near sunset, and heard lots of chirping and whistling. It was the third most amazing science project I have done. The instructions for construction of the antenna were from an excellent book called, "Listen to Radio Energy, Light and Sound", by Calvin R. Graf (now out of print). The other loop I built, I didn't really have to build. It was one of those VHF loops from a portable TV. All I did was add a Germanium diode and plug it into an audio amp. This one was great for picking up all sorts of transmissions at the local airport. Mostly radar and flight path beacons (what are those called)? -Brian Wesley Rich http://www.west.net/~science/