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CX2SA > SATDIG 12.08.20 23:40l 663 Lines 24869 Bytes #999 (0) @ WW
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From: CX2SA@CX2SA.SAL.URY.SOAM
To : SATDIG@WW
Today's Topics:
1. Re: 70cm LNA (Zach Metzinger)
2. Re: 70cm LNA (Kevin Elliott)
3. Re: 70cm LNA (Zach Metzinger)
4. Re: 70cm LNA (W3AB/GEO)
5. Re: 70cm LNA (Kevin Elliott)
6. Re: 70cm LNA (Pedro Converso)
7. Re: 70cm LNA (Zach Metzinger)
8. Re: 70cm LNA (Paul Stoetzer)
9. Re: 70cm LNA (Kevin Elliott)
10. Re: Cubesat Design Specification update call for review
(Joseph B. Fitzgerald)
11. Re: 70cm LNA (Leffke, Zachary)
----------------------------------------------------------------------
Message: 1
Date: Wed, 12 Aug 2020 13:43:03 -0500
From: Zach Metzinger <zmetzing@?????.???>
To: amsat-bb@?????.???
Subject: Re: [amsat-bb] 70cm LNA
Message-ID: <eec23928-5fd4-260f-6427-982e243ad9cd@?????.???>
Content-Type: text/plain; charset=utf-8; format=flowed
On 08/11/20 21:47, Zach Metzinger via AMSAT-BB wrote:
> Success! The SAW filter eliminated the offending cell-tower sources.
> The noise floor barely moves when the preamp is switched in, while
> the desired beacon signal increases significantly.
The 3-D printed passive Lindenblad + homebrew LNA, driving 75' of
look-alike-LMR400 is working well for receiving RS-44 now. The LMR400 is
optional, as there is plenty of gain from the MAX2640 LNA, but was used
to keep losses down when transmitting on this antenna.
I can reliably copy the RS-44 beacon about 8 degrees above the horizon,
and SSB is quite readable at about 20 degrees.
A horizon-to-horizon pass recording is located here:
http://www.n0zgo.net/oscar/rs44_12082020_1802.mp3
(The good stuff starts at about 7 minutes into the recording. I chase
the beacon at the end in CW mode, and it disappears at 5 degrees elevation.)
A FT-847 was used for reception, but a cheap SDR dongle would probably
work just as well for a lost-cost entry into 70cm downlink capability
(as required for the GOLF satellites).
Now to wire it up for automatic Doppler correction and we're in business.
73,
--- Zach
N0ZGO
------------------------------
Message: 2
Date: Wed, 12 Aug 2020 11:54:00 -0700
From: Kevin Elliott <kevin@?????.???>
To: Zach Metzinger <zmetzing@?????.???>
Cc: amsat-bb@?????.???
Subject: Re: [amsat-bb] 70cm LNA
Message-ID: <C8A0FAAC-6BD7-480D-B397-A555455C5721@?????.???>
Content-Type: text/plain; charset=utf-8
Zach,
Are there any complete built filters to inline by chance from any retailer?
Sent from my iPhone
> On Aug 12, 2020, at 11:45 AM, Zach Metzinger via AMSAT-BB
<amsat-bb@?????.???> wrote:
>
> ?On 08/11/20 21:47, Zach Metzinger via AMSAT-BB wrote:
>> Success! The SAW filter eliminated the offending cell-tower sources.
>> The noise floor barely moves when the preamp is switched in, while
>> the desired beacon signal increases significantly.
> The 3-D printed passive Lindenblad + homebrew LNA, driving 75' of
look-alike-LMR400 is working well for receiving RS-44 now. The LMR400 is
optional, as there is plenty of gain from the MAX2640 LNA, but was used to
keep losses down when transmitting on this antenna.
>
> I can reliably copy the RS-44 beacon about 8 degrees above the horizon,
and SSB is quite readable at about 20 degrees.
>
> A horizon-to-horizon pass recording is located here:
>
> http://www.n0zgo.net/oscar/rs44_12082020_1802.mp3
>
> (The good stuff starts at about 7 minutes into the recording. I chase the
beacon at the end in CW mode, and it disappears at 5 degrees elevation.)
>
> A FT-847 was used for reception, but a cheap SDR dongle would probably
work just as well for a lost-cost entry into 70cm downlink capability (as
required for the GOLF satellites).
>
> Now to wire it up for automatic Doppler correction and we're in business.
>
> 73,
>
> --- Zach
> N0ZGO
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
expressed
> are solely those of the author, and do not reflect the official views of
AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 3
Date: Wed, 12 Aug 2020 14:01:59 -0500
From: Zach Metzinger <zmetzing@?????.???>
To: amsat-bb@?????.???
Subject: Re: [amsat-bb] 70cm LNA
Message-ID: <58ad7d75-1175-bf9d-d8d1-75a4bb985aad@?????.???>
Content-Type: text/plain; charset=utf-8; format=flowed
On 08/12/20 13:54, Kevin Elliott wrote:
> Are there any complete built filters to inline by chance from any retailer?
Hello Kevin,
I do not know of anyone offering this filter, and it isn't something
you'd want to transmit through. I don't even know how much power it
would survive before releasing the magic smoke (probably < 1W).
The SAW filter is on the output of the LNA chip, so it is switched out
during TX. You could take your LNA apart and tack this in to achieve the
same effect. You'd laugh at the component-on-it's-side soldering job
with 30ga wire-wrap wire, but it works!
I plan to lay out a board and release it to the community with build
instructions. However, I have another project or two in front of that
before I have free time.
--- Zach
N0ZGO
------------------------------
Message: 4
Date: Wed, 12 Aug 2020 12:07:23 -0700
From: W3AB/GEO <w3ab@?????.???>
To: Zach Metzinger <zmetzing@?????.???>
Cc: amsat-bb@?????.???
Subject: Re: [amsat-bb] 70cm LNA
Message-ID: <d9f7481f-e79b-4658-a702-49d21efab3d2@?????.???>
Content-Type: text/plain; charset=UTF-8
Very nice Zach.
?___
Sent from my two way wrist watch
73 de W3AB/GEO?
On Aug 12, 2020, 11:45, at 11:45, Zach Metzinger via AMSAT-BB
<amsat-bb@?????.???> wrote:
>On 08/11/20 21:47, Zach Metzinger via AMSAT-BB wrote:
>> Success! The SAW filter eliminated the offending cell-tower sources.
>> The noise floor barely moves when the preamp is switched in, while
>> the desired beacon signal increases significantly.
>The 3-D printed passive Lindenblad + homebrew LNA, driving 75' of
>look-alike-LMR400 is working well for receiving RS-44 now. The LMR400
>is
>optional, as there is plenty of gain from the MAX2640 LNA, but was used
>
>to keep losses down when transmitting on this antenna.
>
>I can reliably copy the RS-44 beacon about 8 degrees above the horizon,
>
>and SSB is quite readable at about 20 degrees.
>
>A horizon-to-horizon pass recording is located here:
>
>http://www.n0zgo.net/oscar/rs44_12082020_1802.mp3
>
>(The good stuff starts at about 7 minutes into the recording. I chase
>the beacon at the end in CW mode, and it disappears at 5 degrees
>elevation.)
>
>A FT-847 was used for reception, but a cheap SDR dongle would probably
>work just as well for a lost-cost entry into 70cm downlink capability
>(as required for the GOLF satellites).
>
>Now to wire it up for automatic Doppler correction and we're in
>business.
>
>73,
>
>--- Zach
>N0ZGO
>_______________________________________________
>Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
>to all interested persons worldwide without requiring membership.
>Opinions expressed
>are solely those of the author, and do not reflect the official views
>of AMSAT-NA.
>Not an AMSAT-NA member? Join now to support the amateur satellite
>program!
>Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 5
Date: Wed, 12 Aug 2020 12:26:45 -0700
From: Kevin Elliott <kevin@?????.???>
To: W3AB/GEO <w3ab@?????.???>
Cc: amsat-bb@?????.???
Subject: Re: [amsat-bb] 70cm LNA
Message-ID: <F502FBFA-E3F3-4549-8363-1B7F0E907FB5@?????.???>
Content-Type: text/plain; charset=utf-8
Not wanting to use this with a transceiver, mostly just for my 70cm QFH with
SDR for satnogs. Aware of any other 70cm and 2m LNAs that perform well for
receive-only?
> On Aug 12, 2020, at 12:11 PM, W3AB/GEO via AMSAT-BB <amsat-bb@?????.???>
wrote:
>
> ?Very nice Zach.
>
> ?___
> Sent from my two way wrist watch
> 73 de W3AB/GEO?
>
>> On Aug 12, 2020, 11:45, at 11:45, Zach Metzinger via AMSAT-BB
<amsat-bb@?????.???> wrote:
>>> On 08/11/20 21:47, Zach Metzinger via AMSAT-BB wrote:
>>> Success! The SAW filter eliminated the offending cell-tower sources.
>>> The noise floor barely moves when the preamp is switched in, while
>>> the desired beacon signal increases significantly.
>> The 3-D printed passive Lindenblad + homebrew LNA, driving 75' of
>> look-alike-LMR400 is working well for receiving RS-44 now. The LMR400
>> is
>> optional, as there is plenty of gain from the MAX2640 LNA, but was used
>>
>> to keep losses down when transmitting on this antenna.
>>
>> I can reliably copy the RS-44 beacon about 8 degrees above the horizon,
>>
>> and SSB is quite readable at about 20 degrees.
>>
>> A horizon-to-horizon pass recording is located here:
>>
>> http://www.n0zgo.net/oscar/rs44_12082020_1802.mp3
>>
>> (The good stuff starts at about 7 minutes into the recording. I chase
>> the beacon at the end in CW mode, and it disappears at 5 degrees
>> elevation.)
>>
>> A FT-847 was used for reception, but a cheap SDR dongle would probably
>> work just as well for a lost-cost entry into 70cm downlink capability
>> (as required for the GOLF satellites).
>>
>> Now to wire it up for automatic Doppler correction and we're in
>> business.
>>
>> 73,
>>
>> --- Zach
>> N0ZGO
>> _______________________________________________
>> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
>> to all interested persons worldwide without requiring membership.
>> Opinions expressed
>> are solely those of the author, and do not reflect the official views
>> of AMSAT-NA.
>> Not an AMSAT-NA member? Join now to support the amateur satellite
>> program!
>> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
expressed
> are solely those of the author, and do not reflect the official views of
AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 6
Date: Wed, 12 Aug 2020 16:30:05 -0300
From: Pedro Converso <pconver@?????.???>
To: Zach Metzinger <zmetzing@?????.???>
Cc: amsat-bb@?????.???
Subject: Re: [amsat-bb] 70cm LNA
Message-ID:
<CANTZqKnN4fk+pPNgbVw93zSCvN25z+F8UW9CBeKzXf8dO0NmmQ@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
Nice recording and information, TKS ! for sharing.
As an alternative, http://amsat.org.ar/pass.exe concurrent with HDSDR
could automatic handle & control Doppler on any generic SDR for RS-44
or any other sat.
73, lu7abf, Pedro
,On 8/12/20, Zach Metzinger via AMSAT-BB <amsat-bb@?????.???> wrote:
> On 08/11/20 21:47, Zach Metzinger via AMSAT-BB wrote:
>> Success! The SAW filter eliminated the offending cell-tower sources.
>> The noise floor barely moves when the preamp is switched in, while
>> the desired beacon signal increases significantly.
> The 3-D printed passive Lindenblad + homebrew LNA, driving 75' of
> look-alike-LMR400 is working well for receiving RS-44 now. The LMR400 is
> optional, as there is plenty of gain from the MAX2640 LNA, but was used
> to keep losses down when transmitting on this antenna.
>
> I can reliably copy the RS-44 beacon about 8 degrees above the horizon,
> and SSB is quite readable at about 20 degrees.
>
> A horizon-to-horizon pass recording is located here:
>
> http://www.n0zgo.net/oscar/rs44_12082020_1802.mp3
>
> (The good stuff starts at about 7 minutes into the recording. I chase
> the beacon at the end in CW mode, and it disappears at 5 degrees
> elevation.)
>
> A FT-847 was used for reception, but a cheap SDR dongle would probably
> work just as well for a lost-cost entry into 70cm downlink capability
> (as required for the GOLF satellites).
>
> Now to wire it up for automatic Doppler correction and we're in business.
>
> 73,
>
> --- Zach
> N0ZGO
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
> expressed
> are solely those of the author, and do not reflect the official views of
> AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
>
------------------------------
Message: 7
Date: Wed, 12 Aug 2020 14:36:35 -0500
From: Zach Metzinger <zmetzing@?????.???>
To: amsat-bb@?????.???
Subject: Re: [amsat-bb] 70cm LNA
Message-ID: <d3958c63-ca1b-aa86-c5d5-83ef00c620c4@?????.???>
Content-Type: text/plain; charset=utf-8; format=flowed
On 08/12/20 14:26, Kevin Elliott wrote:
> Not wanting to use this with a transceiver, mostly just for my 70cm QFH
with SDR for satnogs. Aware of any other 70cm and 2m LNAs that perform well
for receive-only?
Hello Kevin,
I've heard good things about LNA4ALL (https://lna4all.blogspot.com/),
which has a high IIP3 and low NF.
The +33dBm IIP3 would help with overload issues on the LNA itself, but
the high gain (+23dB) would then overload your SDR/rig with those, now
amplified, high-power out-of-band signals.
If you added an appropriate filter, such as the one I used, to the
output, then you'd have a good solution.
--- Zach
N0ZGO
------------------------------
Message: 8
Date: Wed, 12 Aug 2020 15:39:08 -0400
From: Paul Stoetzer <n8hm@????.???>
To: Zach Metzinger <zmetzing@?????.???>
Cc: AMSAT BB <amsat-bb@?????.???>
Subject: Re: [amsat-bb] 70cm LNA
Message-ID:
<CABzOSOr+7wurPqyHF8-JFvTDGmurOW-Zx9OXqWOCNfbxM41wKA@????.?????.???>
Content-Type: text/plain; charset="UTF-8"
It looks like they may have re-designed it since I got mine about 7 years
ago, but my 70cm receive only preamp is a High Sierra Microwave LNAA432,
which has a 2 pole SAW filter on the output. It works very well here in my
urban environment (Washington, DC).
http://www.hsmicrowave.com/Amateur%20LNA.html
73,
Paul, N8HM
On Wed, Aug 12, 2020 at 3:37 PM Zach Metzinger via AMSAT-BB <
amsat-bb@?????.???> wrote:
> On 08/12/20 14:26, Kevin Elliott wrote:
> > Not wanting to use this with a transceiver, mostly just for my 70cm QFH
> with SDR for satnogs. Aware of any other 70cm and 2m LNAs that perform well
> for receive-only?
>
> Hello Kevin,
>
> I've heard good things about LNA4ALL (https://lna4all.blogspot.com/),
> which has a high IIP3 and low NF.
>
> The +33dBm IIP3 would help with overload issues on the LNA itself, but
> the high gain (+23dB) would then overload your SDR/rig with those, now
> amplified, high-power out-of-band signals.
>
> If you added an appropriate filter, such as the one I used, to the
> output, then you'd have a good solution.
>
> --- Zach
> N0ZGO
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
> expressed
> are solely those of the author, and do not reflect the official views of
> AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
>
------------------------------
Message: 9
Date: Wed, 12 Aug 2020 12:39:46 -0700
From: Kevin Elliott <kevin@?????.???>
To: Zach Metzinger <zmetzing@?????.???>
Cc: amsat-bb@?????.???
Subject: Re: [amsat-bb] 70cm LNA
Message-ID: <490877E5-9C9F-42DC-9AEB-4D2090460C85@?????.???>
Content-Type: text/plain; charset=utf-8
Yes now just to find filters for 2m/70cm out of the box ready :) Thanks!
> On Aug 12, 2020, at 12:38 PM, Zach Metzinger via AMSAT-BB
<amsat-bb@?????.???> wrote:
>
> ?On 08/12/20 14:26, Kevin Elliott wrote:
>> Not wanting to use this with a transceiver, mostly just for my 70cm QFH
with SDR for satnogs. Aware of any other 70cm and 2m LNAs that perform well
for receive-only?
>
> Hello Kevin,
>
> I've heard good things about LNA4ALL (https://lna4all.blogspot.com/),
which has a high IIP3 and low NF.
>
> The +33dBm IIP3 would help with overload issues on the LNA itself, but the
high gain (+23dB) would then overload your SDR/rig with those, now
amplified, high-power out-of-band signals.
>
> If you added an appropriate filter, such as the one I used, to the output,
then you'd have a good solution.
>
> --- Zach
> N0ZGO
> _______________________________________________
> Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
> to all interested persons worldwide without requiring membership. Opinions
expressed
> are solely those of the author, and do not reflect the official views of
AMSAT-NA.
> Not an AMSAT-NA member? Join now to support the amateur satellite program!
> Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
Message: 10
Date: Wed, 12 Aug 2020 21:07:20 +0000
From: "Joseph B. Fitzgerald" <jfitzgerald@????.???.???>
To: AMSAT BB <amsat-bb@?????.???>
Subject: Re: [amsat-bb] Cubesat Design Specification update call for
review
Message-ID:
<DM5PR22MB08252AA4104D1D4E55A5DDFB87420@?????????????.????????.????.???????.??
?>
Content-Type: text/plain; charset="iso-8859-1"
Looks like real time clocks are allowed to be running while you are in the
deployer. I think this is brand new (they used to be disallowed, and there
is apparently a typo in the conditional requirements specification numbers).
Seems to me like the allowable current limit is about 3 or 4 orders of
magnitude more than necessary. I have seen data sheets for RTC's that need
only a few hundred nA to keep time. Am I missing something?
de KM1P Joe
------------------------------
Message: 11
Date: Wed, 12 Aug 2020 21:27:06 +0000
From: "Leffke, Zachary" <zleffke@??.???>
To: AMSAT <AMSAT-BB@?????.???>
Subject: Re: [amsat-bb] 70cm LNA
Message-ID:
<MN2PR05MB7037EC90318385A9610A3849DF420@?????????????.????????.????.???????.??
?>
Content-Type: text/plain; charset="us-ascii"
In the same spirit of 'releasing to the community' that Zach mentioned,
here's a variation on the design for folks that might be interested:
https://github.com/zleffke/eagle_pga103
This is an EagleCAD design for a PGA-103 based LNA, including the SAW filter
on the *input* (not the output like in Zach's design). I don't have a good
write-up so you'll have to download the repo and open the schematic/board in
Eagle to find the specific parts and values I used. I think I used a
different part then the one Zach mentioned for the SAW filter (more for 433
MHz), but I believe the footprint matches the one he linked to earlier
(Thank you! I've been looking for something better suited for the Ham
bands....if you can find a similar part for VHF I'd be very interested in it
as well!). This does include a 'PTT feature' but that is not a bypass
feature, it is to disable the 5V regulator on the board (As part of a larger
system of external bypass relays and such). It's worth mentioning that if
you install a little jumper on the footprint for the SAW filter instead of
the filter itself, the part works well as a broadband preamp for VHF/UHF as
well...but you obviously lose
the filtering features. I didn't take any meticulous bench measurements
on my final units that I built, so am going strictly off the PGA-103
'datasheet values' for my assumptions on performance (< 0.5dB NF, Gain >20
dB)......basically it works 'well enough' for the on air stuff I used it
for. I'll also note that the datasheet values for the PGA-103 obviously
don't account for having the filter on the input....which will lower the
Gain numbers and increase the noise figure if the filter is used.
I should also mention that the circuit I used was heavily influenced by the
writings of a number of hams about the PGA-103, the ones I can remember off
the top of my head are Kent Britain, WA5VJB and Sam Jewell, G4DDK
(http://www.g4ddk.com/PGA103+2.pdf), Paul Wade, W1GHZ
(http://www.w1ghz.org/small_proj/Simple_Cheap_MMIC_Preamps.pdf) , as well as
Jim Klitzing, W6PQL
(https://www.w6pql.com/LNAs%20(preamps)%20and%20MMICs.htm). I basically
read all their documents and the bias in my design is similar, just tweaked
the layout and used a different 5V vreg (which had some noise suppression
features I liked for the ripple suppression on the 5V output). Kent also
has little general use MMIC boards available on his site wa5vjb.com that are
handy for playing around with the PGA-103s and other MMICs (though they
don't have the SAW filter footprints, just input/output/and bias)
One warning about the above project.....I did make the PCB to match a weird
enclosure that I had on hand at the time, which used funky SMA connectors,
so it has a bit of a 'non-standard' edge launch SMA configuration. That
said the ground planes are all there and some of the bottom solder mask
already removed.....so a little sand paper or razor on the top solder mask
and an edge launch connector should work. Alternatively a coax pigtail
should work with the board 'as is'. I attempted to share this Osh Park
project if someone just wants to order the boards as is directly from Osh
Park ($5.15 gets you three boards):
https://oshpark.com/shared_projects/vIgjua33, but again you'll need to
download the project and read the schematic for the parts and values I used
(all available on digikey/mouser....including the PGA-103 in small
quantities now that Mouser is a vendor for them). If someone is really
itching for it I could probably be convinced to make a PDF of the schematic
and push i
t to the repo.
Finally, I'll mention that I've started a new version of this project in
KiCAD: https://github.com/zleffke/kicad_pga103. That is currently an empty
repo, but I'm close to pushing the Rev- design. The first design I'll be
droppingin that repo will include onboard coax relays for TX/RX sequencing
and the bypass features (I think it will be good up to about 50W through
power). Like Zach mentioned, I have a few other projects 'in the queue' at
the moment but I hope to circle back to this one in the near-ish future to
get it done and out there for folks. I also plan to drop a receive only
version of the design that includes the high pass and low pass filters that
are part of the duplexer design in the Arrow antenna (think arrow
antenna....to PGA-103 based preamp...to duplexer with the filtering for
VHF/UHF work...again receive only...). I also plan to add a generic and
'easier to use' version of the original design linked to in the first
sentence above......but all of that is in the
(hopefully near?) future.
Good stuff! Let's keep building preamps!
-Zach, KJ4QLP
--
Research Associate
Aerospace & Ocean Systems Lab
Ted & Karyn Hume Center for National Security & Technology
Virginia Polytechnic Institute & State University
Work Phone: 540-231-4174
Cell Phone: 540-808-6305
-----Original Message-----
From: AMSAT-BB <amsat-bb-bounces@?????.???> On Behalf Of Zach Metzinger via
AMSAT-BB
Sent: Wednesday, August 12, 2020 3:37 PM
To: amsat-bb@?????.???
Subject: Re: [amsat-bb] 70cm LNA
On 08/12/20 14:26, Kevin Elliott wrote:
> Not wanting to use this with a transceiver, mostly just for my 70cm QFH
with SDR for satnogs. Aware of any other 70cm and 2m LNAs that perform well
for receive-only?
Hello Kevin,
I've heard good things about LNA4ALL (https://lna4all.blogspot.com/),
which has a high IIP3 and low NF.
The +33dBm IIP3 would help with overload issues on the LNA itself, but
the high gain (+23dB) would then overload your SDR/rig with those, now
amplified, high-power out-of-band signals.
If you added an appropriate filter, such as the one I used, to the
output, then you'd have a good solution.
--- Zach
N0ZGO
_______________________________________________
Sent via AMSAT-BB@?????.???. AMSAT-NA makes this open forum available
to all interested persons worldwide without requiring membership. Opinions
expressed
are solely those of the author, and do not reflect the official views of
AMSAT-NA.
Not an AMSAT-NA member? Join now to support the amateur satellite program!
Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
Subject: Digest Footer
_______________________________________________
Sent via amsat-bb@?????.???.
AMSAT-NA makes this open forum available to all interested persons worldwide
without requiring membership. Opinions expressed
are solely those of the author, and do not reflect the official views of
AMSAT-NA.
Not an AMSAT member? Join now to support the amateur satellite program!
https://www.amsat.org/mailman/listinfo/amsat-bb
------------------------------
End of AMSAT-BB Digest, Vol 15, Issue 333
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