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Re: Searching for a very low noise wideband loop preamp
You were right. My mistake. But with Jos¨¦ I was talking about an amplifying device for FM, it was in another YG reflector, and I mixed-up things. Sorry. HI!.
Horacio
?
I agree with Brian, I have had excellent results with the M0AYF broadband loop design.
Easy to build, uses only 2 transistors, unconditionally stable. Many people have
reported it works very well for them. Much less expensive to build your own versus
the Wellbrook or Pixel loops.
?
73, Todd WD4NGG
-----Original Message-----
From: brian nsl < brian.nsl@...>
To: loopantennas < loopantennas@...>
Sent: Wed, Jan 8, 2014 3:16 pm
Subject: Fw: [loopantennas] Searching for a very low noise wideband loop preamp
?
Jose,
???????? I would
recommend that you look at this loop antenna out of interest.
?
-
m0ayf/active-loop-receiving-antenna.html
Broad
Bandwidth?Loop Antenna.?...?The best performing receive antenna
tested was an
-
active loop design by John
(G8CQX) upon which my?....?73,s. Des (M0AYF)
-
There are many ' imitations ' around but it does really
work and is cheap to build.
Good luck with your project.
???????????????????????????????????????????
Regards for 2014,
????????????????????????????????????????????????
72, Brian, G?NSL.
----- Original Message -----
Sent: Wednesday, January 08, 2014 12:14
PM
Subject: [loopantennas] Searching for a
very low noise wideband loop preamp
?
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Re: Searching for a very low noise wideband loop preamp
I agree with Brian, I have had excellent results with the M0AYF broadband loop design.
Easy to build, uses only 2 transistors, unconditionally stable. Many people have
reported it works very well for them. Much less expensive to build your own versus
the Wellbrook or Pixel loops.
?
73, Todd WD4NGG
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Show quoted text
-----Original Message-----
From: brian nsl
To: loopantennas
Sent: Wed, Jan 8, 2014 3:16 pm
Subject: Fw: [loopantennas] Searching for a very low noise wideband loop preamp
?
?
Jose,
???????? I would
recommend that you look at this loop antenna out of interest.
?
-
m0ayf/active-loop-receiving-antenna.html?
Broad
Bandwidth?Loop Antenna.?...?The best performing receive antenna
tested was an
-
active loop design by John
(G8CQX) upon which my?....?73,s. Des (M0AYF)
-
There are many ' imitations ' around but it does really
work and is cheap to build.
Good luck with your project.
???????????????????????????????????????????
Regards for 2014,
????????????????????????????????????????????????
72, Brian, G?NSL.
----- Original Message -----
Sent: Wednesday, January 08, 2014 12:14
PM
Subject: [loopantennas] Searching for a
very low noise wideband loop preamp
?
|
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Re: Searching for a very low noise wideband loop preamp
On 1/9/2014 8:18 AM, Horacio Nigro wrote: .
73
Horacio
Uruguay
This is almost certainly uses an ephemt device. They are great ... above 50 MHz. At HF and below, they have fatal 1/f noise. Rick N6RK
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Re: Searching for a very low noise wideband loop preamp
Hola Horacio,?
This amplifier, you link here, is for VHF and he is looking for Long- , Medium- and Shortwave so he can't use this one.
Best 73?
Rob? PE9PE? Horacio Nigro , 9-1-2014 17:18:
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Re: Searching for a very low noise wideband loop preamp
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?
-----Original Message-----
>From: "Jose A. Kucher" < saguillar@...>
>Sent: Jan 8, 2014 5:14 AM
>To: loopantennas@...
>Subject: [loopantennas] Searching for a very low noise wideband loop preamp
>
>Loop Antenna News and Information Forum
>
>Low noise preamp for wideband loop
>
>Friends im searching for a very low noise wideband loop preamp,
>is for use in areas with very weak Mw signals, my loop is a 3mt
>diameter wire loop and im testing the preamp with two 2n2222.
>
>this preamp have noise in order the signals i want to receive, the
>preamp can receive it, but adding a strong noise floor
>
I just uploaded a revised version of my sketches of low-voltage active antenna amplifiers into the group files section:
Active Antenna Amplifiers for Low Voltage Operation RevA.pdf
They are oriented towards 1.5V applications, but can be used at higher voltages. The first two schematics require that the transistors be parts of a monolithic array, such as the CA3046 or HFE3046. The third schamatic includes feedback for correcting the imbalance when using unmatched transistors, such as individual 2N2222s.
Chris Trask
N7ZWY / WDX3HLB
Senior Member IEEE
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Re: Searching for a very low noise wideband loop preamp
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-----Original Message----- From: "Jose A. Kucher" <saguillar@...>
Sent: Jan 8, 2014 5:14 AM
To: loopantennas@...
Subject: [loopantennas] Searching for a very low noise wideband loop preamp
Loop Antenna News and Information Forum
Low noise preamp for wideband loop
Friends im searching for a very low noise wideband loop preamp,
is for use in areas with very weak Mw signals, my loop is a 3mt
diameter wire loop and im testing the preamp with two 2n2222.
this preamp have noise in order the signals i want to receive, the
preamp can receive it, but adding a strong noise floor
I just uploaded a revised version of my sketches of low-voltage active antenna amplifiers into the group files section: Active Antenna Amplifiers for Low Voltage Operation RevA.pdf They are oriented towards 1.5V applications, but can be used at higher voltages. The first two schematics require that the transistors be parts of a monolithic array, such as the CA3046 or HFE3046. The third schamatic includes feedback for correcting the imbalance when using unmatched transistors, such as individual 2N2222s. Chris Trask N7ZWY / WDX3HLB Senior Member IEEE
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Re: Searching for a very low noise wideband loop preamp
Why not try one of the Wellbrook preamps? ( ?)
73's Egil - LA2PJ
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Re: Searching for a very low noise wideband loop preamp
Hi Jose,
If you are really interested in receiving weak signals, tuned loop will work better than broadband loop.
73, Mike
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Fw: Searching for a very low noise wideband loop preamp
?
Jose,
???????? I would
recommend that you look at this loop antenna out of interest.
?
-
www.qsl.net/m0ayf/active-loop-receiving-antenna.html?
Broad
Bandwidth?Loop Antenna.?...?The best performing receive antenna
tested was an
-
active loop design by John
(G8CQX) upon which my?....?73,s. Des (M0AYF)
-
There are many ' imitations ' around but it does really
work and is cheap to build.
Good luck with your project.
???????????????????????????????????????????
Regards for 2014,
????????????????????????????????????????????????
72, Brian, G?NSL.
----- Original Message -----
Sent: Wednesday, January 08, 2014 12:14
PM
Subject: [loopantennas] Searching for a
very low noise wideband loop preamp
?
|
Locked
Re: Searching for a very low noise wideband loop preamp
What "Loop" no info in your post! 73
Adrian KF7DYU
On Wed, Jan 8, 2014 at 8:54 AM, brian nsl <brian.nsl@...> wrote:
?
Jose,
???????? I would
recommend that you look at this loop antenna out of interest.
There are many ' imitations ' around but it does really
work and is cheap to build.
Good luck with your project.
???????????????????????????????????????????
Regards for 2014,
????????????????????????????????????????????????
72, Brian, G?NSL.
----- Original Message -----
Sent: Wednesday, January 08, 2014 12:14
PM
Subject: [loopantennas] Searching for a
very low noise wideband loop preamp
?
|
Locked
Re: Searching for a very low noise wideband loop preamp
Jose,
???????? I would
recommend that you look at this loop antenna out of interest.
There are many ' imitations ' around but it does really
work and is cheap to build.
Good luck with your project.
???????????????????????????????????????????
Regards for 2014,
????????????????????????????????????????????????
72, Brian, G?NSL.
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Show quoted text
----- Original Message -----
Sent: Wednesday, January 08, 2014 12:14
PM
Subject: [loopantennas] Searching for a
very low noise wideband loop preamp
?
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Locked
Searching for a very low noise wideband loop preamp
?
?
Low noise preamp for wideband
loop
?
Friends im searching for a very low
noise wideband loop preamp,
is for use in areas with? very
weak Mw signals, my loop is a 3mt
diameter wire loop and im testing?
the preamp with two 2n2222.
?
this preamp have noise in order the
signals i want to receive, the
preamp can receive it, but adding a
strong? noise floor
?
Here the loop, in past year DX-camp in
a remote farm in patagonia Argentina
?
?
Jose Kucher, Neuquen
Argentina
?
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The website doesn't mention the input impedance of the amplifier, but it looks like it is fairly high. This
is not optimal for the loop, which works better when loaded with a low impedance.
You can read excellent articles by Chris N7ZWY in the files section of this group to learn more about loop
preamps.
This amplifier may be more suitable for a short whip.
Yes, it's more suitable for short whip (monopole) antennas that require a high input impedance amplifier. Loops have a very low terminal impedance, so a balanced common-base amplifier is more suitable. I have a fairly rigorous one in the files section, and a simpler one was mentioned here recently. Chris Trask N7ZWY / WDX3HLB Senior Member IEEE
|
The website doesn't mention the input impedance of the amplifier, but it looks like it is fairly high. This is not optimal for the loop, which works better when loaded with a low impedance.
You can read excellent articles by Chris N7ZWY in the files section of this group to learn more about loop preamps.
This amplifier may be more suitable for a short whip.
73, Mike
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Thanks info Dave....I was not aware of the history. Steve / 73 Hi Steve,
I used a version of this circuit many years ago as a relay-switched preamp for a homebrew communications receiver, and it worked extremely well ahead of an SBL-1 mixer.
It's essentially cribbed from the "Omega" HF transceiver design by G3WPO and G4JST, which was published in the UK in the mid-80s in the now defunct "Ham Radio Today" magazine. It might be nice if SV1AFN acknowledged this sometime...
A nice design, though, and the SMD implementation is very neat.
Regards,
Dave WEB - "The VE7SL Radio Notebook":
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Does anyone know where I can get the adapter from sma connector to a BNC? dozens on e-bay and with free-shipping to boot! Steve WEB - "The VE7SL Radio Notebook":
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Hi Steve,
I used a version of this circuit many years ago as a relay-switched preamp for a homebrew communications receiver, and it worked extremely well ahead of an SBL-1 mixer.
It's essentially cribbed from the "Omega"? HF transceiver design by G3WPO and G4JST, which was published in the UK in the mid-80s in the now defunct "Ham Radio Today" magazine. It might be nice if SV1AFN acknowledged this sometime...
A nice design, though, and the SMD implementation is very neat.
Regards,
Dave
|
Does anyone know where I can get the adapter from sma connector to a BNC?
Gary WA1TJB
On Friday, January 3, 2014 7:21 PM, Gary Smith wrote:
Looks really interesting. ?Might just order it and try it with my FSL just for fun. ?I already have an 18 db preamp that works very well, but I always like to play with stuff.
Gary WA1TJB On Friday, January 3, 2014 6:15 PM, "ve7sl@..." wrote:
?
Does anyone in the group have experience with this product:
https://www.sv1afn.com/j310preamp.html
It looks to be very well constructed and suitable for a loop preamp.
Steve / VE7SL
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Looks really interesting. ?Might just order it and try it with my FSL just for fun. ?I already have an 18 db preamp that works very well, but I always like to play with stuff.
Gary WA1TJB On Friday, January 3, 2014 6:15 PM, "ve7sl@..." wrote:
?
Does anyone in the group have experience with this product:
https://www.sv1afn.com/j310preamp.html
It looks to be very well constructed and suitable for a loop preamp.
Steve / VE7SL
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Re: RF Systems DX-One Pro MkII - Bi-Loop or not ?
Unfortunately not John.? I do have a Pixel Pro 1B now.? No comparison, the DX-One was WAY better.? In fact I think all in my DX Engineering Active Vertical is better than the Pixel as well. Maybe I am just lucky because this is a pretty low noise QTH but here at least the only thing I get out of the Pixel is directionality and that's just on BCB.? The overall signal levels on the Pixel are a few db lower than the vertical on anything above say 3 MHZ.? Not awful / unreadable but lower than on the vertical and of course there is virtually zero directionality on skywave. I guess if you lived in a noisy environment a loop would be much more beneficial but it hasn't been here,? Perhaps a Wellbrook would be better but there seems to be no consensus on that.? Guy Atkins' tests point to the Wellbrook, Jack Smith's to the Pixel and both of those guys are knowledgeable, creditable sources so maybe its a QTH specific thing.
JMHO.
73, Ian
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Horacio A. Nigro, CX3BZ
Adrian Flynn