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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

I just finished building a few of my improved version of the LZ1AQ, in a box with wing nuts and a few ALA1530 LZ1AQ replacement loop amps. If anyone is interested please contact me off list at everettsharp (at) aol com. Everett N4CY

Hi been playing around with ft8 on 160m.. on psk reporter heard in vk etc.. ( when band open.) tx and rx antenna is a Marconi T. However rx in said directions from here is poor. ( see below.) Live on dartmoor national park ( just,) nice low noise floor. Nice and high (asl) I have crossed parallel loops, delay lines and Lz1aq (5551’s) preamps for rx if I wish. Thing is on 160 the Maroni T beats them.. Now I need to state, my garden is on a BIG slope ( Dartmoor) my rx array is 10m below gnd level of house basement.(20m below roof line.) My garden slopes to west.. Excellent results from south to north, due to clear take off, but though north/ east to south not so good due to antennas below gnd level of house. so i need to improve rx on 160 towards VK etc. Thinking another singular loop on roof ( have pole already erected. Or an short vertical eprobe. Have never used an eprobe, so no idea of performance.. Any thoughts?? please see my qrz page for pic of garden to get idea.bottom of garden is to west of house. Bottom of garden ( gnd) is 20m below roof line. Simon g0zen

I have a SAL-20 antenna for sale. Contact me off list for details. 73l Bill, WA2DVU Cape May. NJ 609 425 8651 bill.riches@...

The following items have been added to the Files area of the [email protected] group. /MODIFIED AMRAD PREAMP - 20 MARCH 2025.docx By: W0LEV <davearea51a@...> Description: Build and technical evaluation with measurements of the Modified AMRAD high-Z input preamp for E-Field probes. Dave - W?LEV

I made the corrections that Martin mentioned and I also add the Bias adjustment procedure to the posting and deleted the 2 original postings. Everett N4CY

The following photos have been updated in the Azi-Loop Self-Supporting Structure for Transportable / DXpedition Use photo album of the [email protected] group. LCU Interior.jpg By: Guy Atkins <dx@...>

Hi All, I found an interesting site, there a archive of the defunct "ham radio" magazine. https://www.worldradiohistory.com/Archive-DX/Ham%20Radio/ I have been reading this article intensively for the past few days. "active antenna preamplifiers by R.W.Burhans, ham radio May 1986" pp.47-54 https://www.worldradiohistory.com/Archive-DX/Ham%20Radio/80s/Ham-Radio-198605.pdf There are things I can't understand. Please someone tell me what they are? About "inductive feedback and input capacitance" that says "A circuit that can reduce the input capacitance and improve the linearity for MOSFETs involves a noiseless feedback method" and "with the FET input capacitance reduced to pratical levels comparable to ..." Does this mean that the inductance and capacitance cancel each other out? Or does the NFB current or voltage physically reduce capacitance? About "active notch" I have tried to the BC band notch between the Probe and the Amplifier or between the Small Loop and the Amplifier, but it does not work well. It seems to be difficult with High-Z or Low-Z line. Putting it in the NFB line looks like a good idea. Have you tried it? Did you get good results? Actually, the MiniWhip I made at the end of last year looks exactly like fig.2 circuit and works well for VLF. it running at http://ja7kbr.proxy.rx-888.com:8073 and I hope to improve it. I have no electrical or physics education (other than Ham radio), so please forgive my naive question. 73, Hisami 7L4IOU

The following items have been added to the Files area of the [email protected] group. /Modified AMRAD eProbe Antenna.pdf By: Everett N4CY <everettsharp@...> Description: Active eProbe antenna

The following items have been added to the Files area of the [email protected] group. /AG5RT/LZ1AQ amplifier noise reduction.pdf By: Mark Whittington AG5RT <mark-whittington@...> Description: LZ1AQ loop amplifier noise reduction I ran an LTSPICE noise analysis of the original LZ1AQ circuit connected to a 3.3 uH loop. I also performed some bench measurements to verify the SPICE results. The analysis and measurements both indicate placing 47 uH inductors in series with the 51 Ohm input emitter bias resistors cuts input referred noise by 2 to 3 dB. This is a substantial reduction. Gain is little effected. Loop diameter can be reduced while maintaining the same input-referred noise level as the original setup. The LTSPICE listings share this directory. Mark AG5RT

After talking with Dave Evans, he noticed that my load resistance slider was at minimum and thought that my radials were too long. He suggested that I raise and shorten them. I raised them from on the ground to 18 inches high and shortened them to 15 feet. That did it! Thanks to Dave! I am satisfied with the antenna and will be able to do better with it after spending more time with it. FX QTH CALL DATE TIME AZ K9AY LOAD AZ LOOP COMMENTS 363 NJ RNB 3 19 1330 330 92-73=19 450 225 87-69-18 30 miles 860 PA WWDB 3 19 1330 310 90-68=22 300 000 80-65=15 990 PHL WNTP 3 19 1330 330 95-65=30 350 000 84-63=21 same tower locatiom 1060 PHL KYW 3 19 1330 320 95-60=35 350 000 78-60=17 same tower locatiom 1150 DE WDEL 3 19 1330 101-86=28 650 240 107-79=28 1210 PHL WPHT 3 19 1330 0 106-83=23 650 010 96-78=18 PERSEUS END

I have just installed an Aziloop and I do not get good nulls - 10 -15 dB on 50 -100-mile ground wave signals, Loop is 13' on long side, 8' on short side and PVC mast is 15 feet. Radials are on the ground below the loop elements. It is fed with about 200' of RG6 cable and the supply voltage is 12.7 volts. I have a SAL-20 antenna 40 feet north of the AZI. I can get 15-30 dB nulls with it. I have a 60 foot self-supported welded steel tower with a large 10–40-meter Mosley beam at the top 42' east of the Azi. Antennas are in the middle of a 1.5 acre lot - no other buildings or metal nearby. Ground elevation is 15 feet ASL. Could these two other antennas be affecting the poor null operation on the Azi? Any suggestions would be appreciated. 73, Bill, WA2DVU Cape May, NJ 609 425 8651

Hello from Austria, I am an enthusiastic mediumwave BC-DXer and operate a small remote station outside Salzburg, which I have built up over the last 14 years. (https://remotedx.wordpress.com/ As I don't own the land, I can't set up endless antennas there. At the moment I use a 200 metre two-wire Beverage and a K9AY (circumference of 30 meter), but it only listens to Asia and South America and is much too close to a house wall. The cows want it that way. But everything can be controlled remotely from QRO.cz, I'm very happy with it. I'm thinking about setting up the ingenious AziLoop, which I could erect a good distance from the houses. The coax there is already buried, so far everything is fine. However, I have two problems at my location: the antenna has to survive storms well, and there are often storms there. And it has to be able to be dismantled quickly, but maybe I can talk my farmer out of that. So I come to the point: I should - although the opposite would be better - erect the antenna as compactly as possible, also because I have to do everything myself. Dave specified a circumference of only 10 meters in his AziLoop manual (page 104). He wanted to cover this topic in more detail in the forthcoming manual, which will be much more comprehensive, but it has not yet been published. In an exciting (and humorous) talk at the Norfolk Amateur Radio Club, he presented the antenna and his thoughts: https://www.youtube.com/watch?v=riQnZ6su_YE&t=2161s - starts at minute 20, the more technical part begins at minute 52. In the presentation Dave showed a circumference of 15 meters, a picture is attached here. This size seems to me to be easily realisable, so my question is whether anyone here already has experience with a ‘relatively’ small AziLoop. My use is only intended from 500-1800 kHz. I have seen the perfect installation from Steve, VK5SFA, in the group - I don't know the exact size, but that seems ‘a size’ too big for me - even if I would do it exactly the same way. Then I would certainly hear AM stations from Australia better in Austria! Thanks for your opinions. 73 Christoph, OE2CRM — https://remotedx.wordpress.com

Guy Atkins <dx@...> added the photo album Azi-Loop Self-Supporting Structure for Transportable / DXpedition Use : My in-progress design uses fiberglass rods to support and tension the lower legs of the triangular loops. Screw hooks along the length of each heat-shrink tubing covered rod allows quick removal of the loop wires (Teflon-covered 20AWG), along with weatherproof connectors that will be used near each pair of 90-deg. angle brackets. I will upload more photos as the design progresses.

Christoph Ratzer <ratzer@...> added the photo album AziLoop Loop Dimension 2025 : In the presentation Dave showed a circumference of 15 meters, a picture is attached here. The following photos have been uploaded to the AziLoop Loop Dimension 2025 photo album of the [email protected] group. AziLoop_YouTube2025.jpg By: Christoph Ratzer <ratzer@...>

Hi, I have made an indoor active broadband loop for HFusing the LAMB-1B amp board from Casarain. Having now got back into amateur radio I want to know if there is anything I can build on the lead to protect against accidental transmission from my rig. If someone could point me in the right direction of a simple circuit Id be much appreciated. Thks. Adam M6RDP

If anyone needs mounting nuts for ARCO and other brands of "padder" or "trimmer" capacitors, I have some that are surplus to my needs. These are almost unobtainium.... VERY hard to find. They are size 12 and have 40 threads-per-inch, solid brass. Charlie, N0TT n0tt at Juno.com

Greetings. I am a frequent "lurker" and very infrequent "poster" to this forum, my interest is primarily MW. I usually use a 1m diameter resonant loop and am puzzled as to why resonant loops seem to be out of favor with most of the group members. The resonant peak provides both "free", noiseless gain to the signal of interest while also rejecting signals at frequencies other than resonance, eliminating the need for high second- and third-order intercept performance. Granted the broadband loops that are much discussed on the forum can acquire broad swaths of the RF spectrum essentially simultaneously, is this a significant advantage given the fact that the frequency of the signal of interest is known? Would someone please discuss the advantages of the broadband loop over a resonant one, have I missed something? Thanks JohnT

If anyone is interested in a loop amp, or a phaser, please contact me off list. everettsharp (@) aol.com Everett N4CY