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Some thoughts on cases for exterior loop antenna amplifiers. This equally applies to any electronics in exterior service. The top of the line cases are polycarbonate, Hammond probably manufactures the best as a mix of price, function, availability. Durable like they are designed for combat. Look up "Hammond Water-Tight ABS & Polycarbonate Enclosures" I've never been able to locate polycarbonate wire glands but black Nylon is probably as durable and UV resistant and readily available on Amazon. For controlled ventilation, the "Hylec vent" is probably the gold standard. This vent allows air flow but blocks humidity. This is what Cross Country Wireless used in my dual polarity horizontal and vertical active dipole. Sadly they come from England and have insanely long delivery times. Honeywell makes one that might be as good, I'll let you know in a year or so. https://www.digikey.com/en/products/detail/amphenol-ltw/VENT-PS1NBK-N8001/7898283 I built a PA0RDT mini-whip for a friend on a tight budget. I drilled a 1/4" hole in the bottom and used Gortex repair tape on the inside and outside. It's been in service for 2 years now and given we've had temperatures ranging from 98F to -10F, over a foot of water, 2 feet of snow (spread out over 2 winters), I suspect the crude Gortext double seal works just fine. However I still do not trust it for anything serious. Given how inexpensive the Honeywell vents are, I'll spring for one and replace the Gortex. Hammond polycarbonate cases are the ultimate and priced accordingly. PVC cases are much more affordable. I use Carlon electrical utility boxes for less serious projects. These feature a neoprene gasket that provides a reasonably good seal and stainless steel screws. I've found Carlon cases to be suitable for many exterior projects and for cases for interior projects. The walls are reasonably thick, the cases reasonably strong, and, the price several years ago was very reasonable [I ended up with oodles when an electrician friend hung up his tools.] A catalog is available at https://carlonsales.com/electrical.php Lowe's used to carry these but appear to have shifted to Cantex. Cantex is similar but uses zinc plated screws, which are guarantied to rust here in Kentucky. I have no experience with the quality of the weather seal in the Contex units. The Carlon utility box is just starting to show some wear from the weather. Our POTS (Plain Old Telephone System) landline NID/DSL filter is in a PVC box. It's sheltered from direct sunlight being on the north side of our home. The phone company supplied the box and internal frame and NID, I added a DSL filter and Cat 5 wiring in the fading dream Windscream, er sorry, Windstream will extend DSL out to where we are and I can give up a Consumer Cellular phone based WiFi hotspot. Oddly enough the local electrical inspector approved Cat 5 wiring from the Windstream NID to inside our home with no comments about "You need transient protectors." I guess the Tii belcore lightning transient in the NID qualifies. https://tiitech.com/wp-content/uploads/datasheets/surge-arresters/356.pdf They meet UL 497 and Telcordia GR-1361 Core protection requirements. They also installed a NID case more suited to an 8 dwelling apartment building, too bad I can't legally do anything with the spare space. The installation tech allowed me to install the DSL filter. Nice of her. The GTE PVC box at my parents home was at least 40 years old when we sold the home and still in good shape and it was on the south east side of the house and received hours of direct sunlight. So PVC might be OK for extended service. I'll continue to use PVC for casual projects but for my CCW dual polarity H/V antenna and my N4CY loop amps, I'll go with the Hammon polycarbonate cases even though the PVC cases I've used for the N4CY looks have held up nicely. OK a bit of theory here. I suspect we have water ingress because the changing temperature, cooler, sucks in moisture laden air, by having a vent that allows air but blocks all humidity, we don't get condensation. A life time ago when I went for

Hi everyone I wondered what schematic design software other members use. I've tried one or two free downloads but struggled to get good results and so I wondered if there was some free or very low cost design software that members could recommend that doesn't have too steep a learning curve. Thanks in advance Chris Sentance

Hi All, Long time reader. I enjoy this group. First post. My health is lacking. I walk with a cane. I will leave it at that. Antennas must must be low to the ground as I cannot climb or put up wire antennas to any sort of height. I am very interested in setting up a broadband loop antenna to listen and log. Perhaps to use it as a second receiver. Steve, AA7U has been helpful to me and I thank him. I decided to post here and learn. I have read extensively in the files area and have looked at lots of pictures and read much about the rf amplifiers. I can make most everything I will need, and am very experienced in building manhatten or SMD (yes I can still do that! :-) with my magnifiers. I have, a scope, sig gen, DSA 815-TG, power supplys, VNWA/3E, and hako soldering equipment including the FR-301 (Handy for fixing radios!) and most all the other equipment as well. Meters, most PEAK tools (LCR DCA55,ESR70) I would like to build my own things. I read this article on top of what was posted here and was impressed with it. I would like to get your feedback on this. https://swling.com/blog/2016/03/guest-post-building-a-magnetic-loop-antenna-broadband-amplifier-for-your-sdr/ I am also interested in what Joe and Steve have done with amplifiers. I would prefer not to have to order from europe and make my own. /g/loopantennas/files/APracticalApproachToBuildingABroadbandActiveLoop.pdf Thanks for this group! 73 Guy N1GMM https://www.qrz.com/edit/N1GMM -- 73/ Guy, N1GMM Web Presence: Withywindle ( https://niggles-parish.blogspot.com/ ) tom-bombadillo ( https://tom-bombadillo.blogspot.com/ )

I wonder if anyone here has had any experience of the XG189? I recently bought one and it seems to work in a lashed up table top experiment using a sig gen and a dual channel scope.. I am particularly interested in any RF antenna experiments and findings from members here. Pete Worrall G4GJL

What happens if, instead of the 4+4 2SK715 FETs used in the schematic of the ALA1530, I will use only 2 + 2 ? I have only 5 of those FETs, so cannot build the schematic in its original form... Are modifications needed to the number of turns of T1 ? There will be a substantial degradation of the performance ? Thanks for any suggestion. 73 Alberto I2PHD

Is there a place where group owners/moderators can chat? I'm new to this (so new it's embarrassing) and there are so many things I need to learn. Like what's allowed/disallowed, is there a way to politely inform a poster "you've crossed a line, please don't again," and similar topics. We can delete this thread after it has served it's purpose. Note: I will be extremely busy from now until August 29 (more likely until September 1) with preps for and then undergoing surgery. If it's like the last time, I will be undopped August 31. I don't like opiates and they don't like me. I started PT the last time 2 days after surgery, this time it will be the day after surgery and the first few PT sessions wipe one out. Oh and I completed PT for my right knee yesterday August 13, got a nice "diploma" to hang on the wall. Note 2: If (when) you have major surgery, do not forgo the PT, it sucks bilgewater to quote a friend, but the surgeon finishes in an hour, the PT techs work with you for weeks to months. A guy at the club where we use the pool and equipment was bad mouthing my surgeon before I had surgery, I asked "Did you do PT?"" "Of course not! I don't have time for that !@#$." And he wonders why his left leg is nearly frozen. He scowls at me when I every time I went up the stairs for the last two weeks to the saunas (hey it's my wife's idea) because my right leg moves so freely. It's all I can do to not giggle at his self inflicted unhappiness.. You have perhaps 3 months to rehab major joint replacement. Oh, I am not a gym rat, I !@#%ing hate exercise, but I accept I'll live longer and healthier if I start taking care of this old body. Enough said.

Greeting to everyone. I have been a lurker/reader of this forum and finally have a contribution. Check-out ===> http://www.sonic.net/~n6gn/OSHW/ to see some of the 'kits' N6GN has developed that you can order from a Chinese FAB business. Several members of the wsprdaemon and Hamsci groups are using Glenn/N6GN hardware to great success. 73 Dick/w7wkr

On Tue, Aug 13, 2024 at 09:49 AM, wn4isx wrote: I logged into Groups IO like normal and there is a blue box with owner inside. Does this mean I've been elevated to group owner by mistake? Yes, that does mean the group's original Owner (Steve Greenfield) has selected you as one of the group's Owners. An Owner is like a super-Moderator. You have the power to create and destroy. You might recall Steve wrote that he had a recent stroke. I think he wants to make sure at least a few active group members are able to carry-on in case he can't for some reason. I think he did not do it "by mistake", but I am not him. As one of the Owners, you don't need to do anything. Just don't screw it up by deleting things that should not be deleted. And hopefully you will be with the group for a while so that you could - if needed - step in if Steve can't. The problem with some groups is that they have only one Owner, and if that Owner goes missing for any reason, the group dies and can't continue like it used to. You will probably start to receive auto-generated messages whenever anyone joins or leaves the group, and several other status messages. You can ignore them. You can even disable those messages, and act as if you are a normal member. Heck, I think you can even edit your own membership status so that you go back to being a regular member again and not an Owner, if that is what you want. If you want help knowing what you can do, I may be able to help a little with that. Andy

Does anyone know what cases CCW uses? I've decided to "recase" my dual HF polarity CCW active dipole. Originally it used Ethernet cable but, given the difficulty of complying with the NEC and my need to extend beyond the length of the supply cable, I've decided to switch to coax. I've done a crude butcher kludge that works but I have zero faith on the weather tightness of my hatchet job. CCW cases are perfect for antenna becuase the plastic doesn't degrade in direct sunlight. I think I've had my unit outside and operational for 5 years. A quick cleaning with some baby wipes and the plastic looks as good as the day it was new. And no I am not going into the antenna (or anything) manufacturing business. Thank you

I thought this deserved it's own thread. A quick report on the Multi-function Tester (TC-V2.12k) https://www.circuitspecialists.com/content/430516/csi-tc1.pdf They is very functional, it quickly allows one to ID bipolar/fet NPN/PNP N-channel/P-channel. The Hfe function is pretty good, the Idss less so because the bias current is too low. It showed all of my test samples of ~1980 Ti 2N3819 as being closely matched where as the JFET-matcher-rullywow.com-Build-Doc-v1.01.pdf is much more picky and probably more relevant because of the higher bias. Having said this, the TC-V2 is a very useful test device, well worth the cost.

Hello, I recently finished my cross parallel loop (commercial LZ1AQ amp). It works well in A+B mode. But looks like local AM broadcast stations cause an overload in Dipole mode. Antenna is mounted on my townhouse balcony as you can see on a picture. It's a semi-urban quite RF noisy environment (SF Bay Area in California). Using it with SDRPlay RSPDx. From what I see all the intermodes are from the loops high Z amplifier, not from my SDR. I see none of that in Loop mode. I continue seeing that on 40m band. Now 20m and 10m are clean from IMDs but sensitivity seems to be much lower compared to loop mode low-Z amp. Which is probably a result of de-sensing caused by amp being oversaturated from MW. And I had hope for Dipole mode on higher bands but looks like it's quite useless in my conditions. Now, since RSPDx is missing a dedicated 160m bandpass filter it can easily be saturated with any antenna that I have on 160m. I tried multiple loops, my 10-80 EFHW. A dedicated preselector like MFJ 1046 placed between antenna and SDR takes care of that. Same story with this new cross looped LZ1AQ: no issues on 160m in any Loop mode if I use a preselector after it. Which tells me that local AM MW stations don't saturate loop mode amp, only saturate a preamp in SDR. And of course preselector doesn't help in Dipole mode at all. So, is that kind of behaviour to be expected in relatively noisy environment from LZ1AQ Dipole amp? Or am I missing something in my setup? Thank you, Simon P.S. Links below will show a picture of my antenna and Dipole mode reception on 80m: https://photos.app.goo.gl/qYxNVAExHqvYHuwS8 https://photos.app.goo.gl/CC993JVz7Q2gTQcQ8

I have a Wellbrook Broadband Phaser for sale. If anyone is interested please contact me at Everettsharp (at) aol com Everett N4CY

If anyone is interested I just finished building 5 LZ1AQ boards and Bias Tees. The new design eliminates the need to solder anything. I also added protective diodes on the input. The bias tee has a polyfuse to protect the system in the event there is a short in the coax. If interested please contact me off list at everettsharp@... everettsharp (at) aol com. Everett N4CY

We're trying to get our LZ1AQ going. We're trying to get our LZ1AQ going. It is working but seems to have very poor sensitivity. It is being compared to an existing MLA-30 loop and is quite a bit less sensitive. Also seems to have more noise than the MLA-30. We have configured it as a Single Loop and our antenna construction is using 1-inch PEX-AL-PEX "Fat Loop" design around 1m diameter as described in technical documentation. It is mounted 1m above ground on an antenna rotator. The support structure is made of PVC piping. Controller Card is connected to Amplifier with 75-ft of CAT-6 cable. The receiver is an SDR-Play-Duo. We are hoping someone can give us some pointers on what our problem possibly may be. Perhaps some jumper is set wrong? It seems to work better with Counterpoise wire on V2 (+A/-A), but uncertain on if this is really needed. What other issues are typical? THX

Hi everyone, After some emails with G8JNJ and several hours reading this group, I finally decided to write my first post. I live in a medium-sized city, and my large 1/2 wave inverted V antennas are picking up quite a lot of man-made noise. I only work 80, 40, and 20m bands (Lower HF). So, I would like to try an active small loop to see if I can improve my poor SNR. After some reading, two designs caught my attention: LZ1AQ: Quite popular for LF and MF, but not so much for HF. Its low input Z is suboptimal for a small loop at HF (around 1 meter diameter). Although it has an input matching network, below HF is where it really shines. M0AYF Improved: Input Z is more HF-friendly for a 1m loop without the need for a matching network, but CMR, IP2, and IP3 seem to be a bit worse than the LZ1AQ. Which design will be better suited for 3.5-14MHz? Additionally, which design is easier to filter for rejecting MF and FM broadcasts? I've also read that for urban use, most designs behave similarly. TIA !!!!

The following files and folders have been uploaded to the Files area of the [email protected] group. /Simplified Lankford Phaser.pdf By: Everett N4CY <everettsharp@...> Description: New Simplified Phaser Design

Hi Henry, Unfortunately I don't have info on these earlier versions such as your 1530L. Steve AA7U On 7/23/2024 9:41 PM, tardivat via groups.io wrote:

I am not trying to start a flame war over "proper feedline entry to a residence." I live in the USA and have to comply with the NEC, National Electric Code. For coax it's pretty simple, ground the braid and you are legal, but, how on earth do you properly apply UL (Underwritters Laboratory) lightning protection to Ethernet cable? I believe every state in the USA has adopted the NEC, different states have adopted different versions, states and "authority having jurisdiction" (cities) have modified their interpretation in different ways. I talked with the statewide "authority having jurisdiction" and was told Kentucky is using the 2017 code but is working to update to the 2023 code "As soon as possible." If an antenna/feedline installation doesn't meet code, then insurance companies can legally refuse to pay for any lightning damage, even if it comes in on the cable TV, telephone, or AC mains. I'm experimenting with Ethernet and presently just run it out the window when I'm using it, bag it and toss it outside when I'm finished. I have a piece of nylon monofilament tied to the bag to bring it back in, but, it is a PITR (rump) and I'd like to do this legally. So far I've found this: https://www.polyphaser.com/surge- protector-5-pair-100base-t-ethernet-ix-5h https://www.polyphaser.com/Images/Downloadables/Datasheets/IX-5H_datasheets_US.pdf Two problems, 1) the Ethernet cable has to be undone for screw connections, which ought to do wonders for the balance. 2) The UL rating: "UL 497B provides requirements for protectors used in communication and fire alarm circuits." Any ideas? Note 1: People in other countries can have extremely different rules, so what works here might be illegal there and what works there might be illegal here. Note 2: If I'd ever turned in an engineering paper written half as poorly as anything in the NEC, they'd have kicked me out of school. I swear they must work overtime to make it as obtuse as possible and still use English. Note 3: I installed the 'home end' of my CCW dual polarity LF~HF antenna outside and ran coax from the bias-t inside with the shield properly grounded and DC power outside, being paranoid careful to comply with the NEC. [Cursed be their name.]

When Wellbrook was in business I used to buy a new FLG100LN every year due to nearby lightning discharge zapping it. Now I make my own, using one of Everett's boards. My current one died last week--there was a nearby discharge that came over before I could go out and disconnect everything. I repaired it today, second time I've repaired one. This had 3 bad jfets on one side and one bad jfet on the other side. Both bipolars were good. You have to remove all the jfets before you can find the bad ones. I use an inexpensive tester, "TC1", that does a good job testing jfets (and lots of other things too, of course). 73, Steve AA7U

John Hudak showed me a nice schematic he'd made of mine which I've put in my Wellbrook file in Photos, replacing my hand-drawn one. Thanks, John. /g/loopantennas/album?id=296460 73, Steve AA7U