Re: What Loop to Use With LZ1AQ Amp by N4CY
Hello Martin. I
found Mikek's question and your answer very interesting and made
me ponder.
What differences could or would be noticed between these two
different loop designs (one of much lower inductance than the
other) given that both will be active and broadband and using the
same balanced circuitry?? My interests are only at VLF and lower
and I wonder what differences I would see on my receiver. ?
Gedas, W8BYA EN70JT
Light travels faster than sound.....
This is why some people appear bright until you hear them speak.
On 11/1/2024 12:38 PM, Martin -
Southwest UK via groups.io wrote:
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Hardly any difference in inductance, approx 2.28uH vs. 2.39uH
for the thinner stuff.
?
If you really want to decrease the inductance, connect two
loops in parallel, spaced by approx 1 radius.
?
Using the thinner tube and two loops spaced by 18 inches
gives approximately 0.63uH.
?
All from the on-line VK3CPU Magloop Antenna Calculator
?
?
Regards,
?
Martin
?
On Fri, Nov 1, 2024 at 04:22 PM, Mikek wrote:
It might be a bit harder to shape, but would it have a
slight advantage?
Can someone calculate how much lower the inductance would
be?
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Re: What Loop to Use With LZ1AQ Amp by N4CY
On Fri, Nov 1, 2024 at 09:38 AM, Martin - Southwest UK wrote:
Hardly any difference in inductance, approx 2.28uH vs. 2.39uH for the thinner stuff.
?
If you really want to decrease the inductance, connect two loops in parallel, spaced by approx 1 radius.
?
Using the thinner tube and two loops spaced by 18 inches gives approximately 0.63uH.
?
All from the on-line VK3CPU Magloop Antenna Calculator
?
?
Regards,
?
Martin
?
?? Thanks, for that!
??????????? Mikek
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Re: What Loop to Use With LZ1AQ Amp by N4CY
Hardly any difference in inductance, approx 2.28uH vs. 2.39uH for the thinner stuff.
?
If you really want to decrease the inductance, connect two loops in parallel, spaced by approx 1 radius.
?
Using the thinner tube and two loops spaced by 18 inches gives approximately 0.63uH.
?
All from the on-line VK3CPU Magloop Antenna Calculator
?
?
Regards,
?
Martin
?
On Fri, Nov 1, 2024 at 04:22 PM, Mikek wrote:
It might be a bit harder to shape, but would it have a slight advantage?
Can someone calculate how much lower the inductance would be?
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Re: What Loop to Use With LZ1AQ Amp by N4CY
On Fri, Nov 1, 2024 at 07:32 AM, Everett N4CY wrote:
Go to amazon, or elsewhere and buy 5/8" aluminum gas tubing. It is easy to bend by hand, just make a 3' circle on your driveway and form it to the circle. It is very lightweight and is much better that copper.
? I see Amazon also has 3/4" aluminum with a 0.05" wall thickness.
It might be a bit harder to shape, but would it have a slight advantage?
Can someone calculate how much lower the inductance would be?
?Just being curious.
??????????????????????????????????? Mikek
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Re: What Loop to Use With LZ1AQ Amp by N4CY
On Fri, Nov 1, 2024 at 02:28 PM, Larry Naumann wrote:
I am thinking of just a simple 1/2¡± copper pipe 36¡± diameter loop or maybe a ¡°shielded¡± design
Everetts LZ1AQ type amplifier is fully balanced, therefore a shielded loop offers no advantage. A Diameter of 36" ist perfect, but if you are mainly interested in LW and MW a slightly larger loop diameter of for example 4 feet (1,20m)? may be favorable.
?
regards
Fred
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Re: What Loop to Use With LZ1AQ Amp by N4CY
Thanks Everett, you refreshed my memory on that. I recall researching that in the past.
Larry n0sa
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Re: What Loop to Use With LZ1AQ Amp by N4CY
Larry,
?
Go to amazon, or elsewhere and buy 5/8" aluminum gas tubing. It is easy to bend by hand, just make a 3' circle on your driveway and form it to the circle. It is very lightweight and is much better that copper.
?
Everett N4CY
In a message dated 11/1/2024 9:29:01 AM Central Daylight Time, n0sa@... writes:
?
Awhile back I obtained a LZ1AQ amp board from N4CY.
I am now ready to build the loop for it.
I have read a lot of posts and files but can¡¯t decide on what loop to build for it.
I am mainly interested in LW and MW.?
I live in a noisy suburban area.
I am thinking of just a simple 1/2¡± copper pipe 36¡± diameter loop or maybe a ¡°shielded¡± design inside the copper tubing.
Possibly multi turns inside the copper tubing.
I am looking for suggestions.
Thanks
Larry
n0sa
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What Loop to Use With LZ1AQ Amp by N4CY
Awhile back I obtained a LZ1AQ amp board from N4CY.
I am now ready to build the loop for it.
I have read a lot of posts and files but can¡¯t decide on what loop to build for it.
I am mainly interested in LW and MW.?
I live in a noisy suburban area.
I am thinking of just a simple 1/2¡± copper pipe 36¡± diameter loop or maybe a ¡°shielded¡± design inside the copper tubing.
Possibly multi turns inside the copper tubing.
I am looking for suggestions.
Thanks
Larry
n0sa
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Re: Interesting upgrade for a Youloop
Hi Paul,
?
I also I believe Youssef is very talented, and he has undoubtedly made some significant contributions to the general SDR technology, and I genuinely wish I was as skilled as him.
?
I can also think of several other developers who are a brilliant, but somewhat temperamental, and I've been kicked off several groups and mailing lists devoted to specific products, for flagging up problems, with both hardware and software, only to be later proven correct. I've always tried to be factual and non-confrontational, but the bans often remain in place.
?
However, IMHO, I still don't rate the YouLoop. It's unnecessarily complicated, and a simple comparison with a similar sized unscreened single turn loop would generally perform as well as, or better than, except perhaps on frequencies below approx 1MHz. From this, I conclude that a lot of users may judge the antenna based on MW broadcast reception, but I may be wrong.
?
But, like a lot of antennas, and generally speaking, no one can be bothered to perform any tests, and they just believe whatever they want to believe, without letting anything sway their opinion.
?
Have a look at the Antenna reviews on sites like QRZ.com, many of the excellent reviews have nothing to do with the actual product, it's more about self-justifying the purchase, the sales experience, quality of after sales support, and what DX has been worked, without specifying the frequency, mode and power being used. Basically, it's nearly all subjective and emotionally based, rather than being factual.
?
To quote Public Enemy - "Don¡¯t Believe the Hype" :-)
?
Regards,
?
Martin
?
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On Fri, Nov 1, 2024 at 06:29 AM, Paul White wrote:
At the risk of sounding like a fanboy, I'd add that Youssef is one of those with a special kind of vision.
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Re: Interesting upgrade for a Youloop
Thanks for clarifying Fred :D.
At the risk of sounding like a fanboy, I'd add that Youssef is one of those with a special kind of vision.
Who doesn't suffer fools (like me) gladly and so (predictably) in turn pisses me off from time to time ;)
But the wins keep coming.
All the best
Paul
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Re: Interesting upgrade for a Youloop
When I was working, a sales director once said to me, don't let the customer anywhere near the engineers / developers, as they tend to focus on the negative aspects of our products.
?
A purchasing director said to me, if you can, get to speak directly with the engineers / developers, they will tell you what's wrong with their product, how it can be improved, and why their competition's product is better, they just can't seem to help themselves.
?
It's all true, I have seen, and heard, of many excellent sale pitches, ruined by careless talk by engineers. They are generally not skilled when presentation and interpersonal skills are required, rather than engineering expertise.
?
It is rare to find an engineer or developer that has both sets of skills, and to be really successful you also need to be a psychopath, but that's a conversation for another day...
?
Regards,
?
Martin
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On Thu, Oct 31, 2024 at 06:54 AM, Fred M wrote:
Software engineers are often a bit NERD like a and not particularly interested in sales and marketing.
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Re: Interesting upgrade for a Youloop
On Wed, Oct 30, 2024 at 05:06 PM, Paul White wrote:
On Wed, Oct 30, 2024 at 03:42 PM, Fred M wrote:
He is also very talented in marketing.
Not sure how to take that.
?
Software engineers are often a bit NERD like a and not particularly interested in sales and marketing. However Youssef as developer and president of Airspy seems to be very skilled to put his products and their advantages into the spotlight and made Airspy a worldwide commercial success.
?
regards, fred
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Re: Interesting upgrade for a Youloop
On Wed, Oct 30, 2024 at 03:42 PM, Fred M wrote:
He is also very talented in marketing.
Not sure how to take that.
?
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Re: Interesting upgrade for a Youloop
On Wed, Oct 30, 2024 at 02:36 PM, Martin - Southwest UK wrote:
Youssef is a very bright software engineer, with many talents
He is also very talented in marketing.
?
regards
Fred
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Re: Interesting upgrade for a Youloop
In conversation with Youssef on the Airspy IO group, during the early days of the Youloop, we argued about the design, and the high impedance "hump" in the middle of the operational frequency range, he then progressively stated several interesting "snippets" of information.
?
It requires a receiver with a very good noise figure
The HF discovery input impedance had been optimised for use with the Youloop, and that 50 ohms was not ideal
He featured what he considered to be a suitable pre-amp design, that was based on a guitar pre-amplifier, which had a high value of input impedance
?
Youssef is a very bright software engineer, with many talents, but I still don't rate his antenna.
?
Just my personal opinion, your mileage may vary.
?
Regards,
?
Martin
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Re: Interesting upgrade for a Youloop
"YouLoop"? to my knowledge is an acronyme for "Youssef Loop" Youssef Touil is the developer of the airspy SDRs and the programmer of the famous SDR# Software. Because of the exceptionally good sensitivity of the airspy HF+ and Airspy HF discovery SDRs, a passive loop is sufficient to achieve a surprisingly good reception. Youssef Toul proposed a passive moebius-strip type loop and called it "Youloop". Following the demand from customers, he decided to offer the semi-rigid two-turn "YouLoop" as a ready built product that is sold as? "Noise-Cancelling Passive Loop (NCPL)" for portable DX-ing via the airspy distributors network.?
?
?
Meanwhile the majority of YouLoops sold on eBay and Aliexpress? are chinese "copyshop" clones and no genuine Airspy products.
?
regards
Fred
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Re: LZ1AQ using BFU590QX transistors
Hi Bernard,
I changed nothing, both boards had the same components.
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On Oct 30, 2024, at 3:47?AM, Bernard Malet via groups.io <malet-bernard@...> wrote:
?
Hello Everett
Between these two versions of transistors, have you changed any component values on your PCB
Best regards
Bernard
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Re: Interesting upgrade for a Youloop
Hi Zack,
?
The SMA switch looks to be good enough for your purpose.
?
They are using miniature PCB mount relays, which are usually good performers, and can be used for transmit purposes up to a moderate power level.
?
My only concerns are the 0-150MHz frequency range, which I would have thought should have been OK up to at least 500MHz (I have used them up to 1GHz), and the amount of isolation between ports, which is as equally important as the value of through loss.? They do publish some performance graphs, but they have not annotated them, so they are not easy to interpret.
?
Regards,
?
Martin
?
?
On Tue, Oct 29, 2024 at 10:52 PM, Zack N8FNR wrote:
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Re: Interesting upgrade for a Youloop
Hi Zack,
?
Let me start out by saying IMHO, I'm not a believer in Youloops. I think it is a marketing strategy to make the design stand out from the crowd, without it having any firm technical basis for the claims made about it.
?
I also have doubts about the company you provided a link to. Although looking like a Western shopfront, they are in fact based in China. Nothing wrong with that, but they don't give their trading address on their website (or at least I couldn't find it), which to me is always a red flag. I do however notice it is on their Facebook page, so why don't they put it on their website ?
?
The amplifier itself seems OK, and some thought seems to have been put into the design. They also publish some specifications, and if genuine, they should give some sort of indication regarding the level of performance it is likely to provide, which I would rate as Meh...
?
However, the main point of my post is, why do this ?
?
The combined cost of an "official Youloop, plus the Balun / amplifier box and Bias Tee, works out as around $100 USD, before shipping and taxes etc.
?
An official LZ1AQ switched loop / dipole amplifier, with a very high level of specification works out at around $115 USD, before shipping and taxes etc. Which is only just a little bit more than the previous items.
?
https://active-antenna.eu/amplifier-kit/
?
"Putting lipstick on a pig" (or something ruder, involving glitter) springs to mind...
?
Regards,
?
Martin
?
?
On Tue, Oct 29, 2024 at 10:52 PM, Zack N8FNR wrote:
and also found this Youloop upgrade. Anyone tried this?
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Re: LZ1AQ using BFU590QX transistors
Hello Everett
Between these two versions of transistors, have you changed any component values on your PCB
Best regards
Bernard
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Larry Naumann
Everett N4CY