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Ham shack satellite communications

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  Ham shack satellite communications "Don" <g@crcomp.net> - 2026-09-14 15:14 +0000
    Re: Ham shack satellite communications Cóilín Nioclásín Glostéir <thanks-to@Taf.com> - 2026-09-15 20:13 +0000
      Re: Ham shack satellite communications "Don" <g@crcomp.net> - 2026-09-15 21:40 +0000
        Re: Ham shack satellite communications Jan Panteltje <alien@comet.invalid> - 2026-09-16 07:45 +0000
          Re: Ham shack satellite communications "Don" <g@crcomp.net> - 2026-09-16 11:56 +0000
    Re: Ham shack satellite communications Don Y <blockedofcourse@foo.invalid> - 2026-09-16 05:54 -0700
    Re: Ham shack satellite communications Gerhard Hoffmann <dk4xp@arcor.de> - 2026-09-16 15:37 +0200
      Re: Ham shack satellite communications Gerhard Hoffmann <dk4xp@arcor.de> - 2026-09-16 15:42 +0200
      Re: Ham shack satellite communications Jan Panteltje <alien@comet.invalid> - 2026-09-16 14:25 +0000
        Re: Ham shack satellite communications Gerhard Hoffmann <dk4xp@arcor.de> - 2026-09-16 16:56 +0200
          Re: Ham shack satellite communications Jan Panteltje <alien@comet.invalid> - 2026-09-16 17:59 +0000
            Re: Ham shack satellite communications Gerhard Hoffmann <dk4xp@arcor.de> - 2026-09-16 20:17 +0200
        Re: Ham shack satellite communications john larkin <jl@htigct.com> - 2026-09-16 11:31 -0700
          Re: Ham shack satellite communications Gerhard Hoffmann <dk4xp@arcor.de> - 2026-09-16 21:28 +0200
            Re: Ham shack satellite communications "Don" <g@crcomp.net> - 2026-09-16 19:57 +0000
            Re: Ham shack satellite communications john larkin <jl@htigct.com> - 2026-09-16 13:18 -0700
              Re: Ham shack satellite communications Gerhard Hoffmann <dk4xp@arcor.de> - 2026-09-17 00:22 +0200
            Re: Ham shack satellite communications Jan Panteltje <alien@comet.invalid> - 2026-09-17 06:12 +0000
      Re: Ham shack satellite communications "Don" <g@crcomp.net> - 2026-09-16 14:54 +0000

#747728 — Ham shack satellite communications

It seems best to start with the receiver. Here's one simple receiver
schematic:

eggbeater antenna -> LNA -> LMR 220 -> RTL-SDR -> FreeBSD

What's your favorite eggbeater and why?

What's your favorite LNA and why?

Thank you in advance.

Danke,

--
73, Don, WD7Q                                             veritas    _|_
                                                          liberabit   |
https://www.qsl.net/wd7q                                  vos         |

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#747783

Maybe ask persons who use AmSat (an amateur-satellite initiative).

(S. HTTP://Gloucester.Insomnia247.NL/ fuer Kontaktdaten!)

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#747784

Typo in original post corrected.

Cóilín Nioclásín Glostéir <thanks-to@taf.com> wrote:
> Don wrote:
>>
>> It seems best to start with the receiver. Here's one simple receiver
>> schematic:
>> 
>> eggbeater antenna -> LNA -> LMR 200 -> RTL-SDR -> FreeBSD
>> 
>> What's your favorite eggbeater and why?
>> 
>> What's your favorite LNA and why?
>> 
>> Thank you in advance.
>
> Maybe ask persons who use AmSat (an amateur-satellite initiative).

Joseph A. DiVerdi [1] hosted a last minute, surprise forum at our 
Division's Ham Convention [2] last August. He brought along a 3U
satellite to show off at his vendor's table.
    Instead of thrusters, it spins a miniature momentum wheel. A de
rigueur RTL-SDR and Raspberry Pi sat next to the satellite on his table.
    Long story short, an EB144RK2M eggbeater will be used, along with a 
cheap LNA module from ebay [3]. It ought to be easy enough to replace 
the original LNA chip, if anyone knows of a superior LNA chip.

Note.

[1] <https://diverdi.colostate.edu/>
[2] <https://wyohamcon.org>
[3] <https://www.ebay.com/itm/198551314050?_trksid=p2332490.c101875.m1851>

Danke,

--
73, Don, WD7Q                                             veritas    _|_
                                                          liberabit   |
https://www.qsl.net/wd7q                                  vos         |

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#747789

>"Don" <g@crcomp.net>wrote:
>>Typo in original post corrected.
>
>Cóilín Nioclásín Glostéir <thanks-to@taf.com> wrote:
>> Don wrote:
>>>
>>> It seems best to start with the receiver. Here's one simple receiver
>>> schematic:
>>> 
>>> eggbeater antenna -> LNA -> LMR 200 -> RTL-SDR -> FreeBSD
>>> 
>>> What's your favorite eggbeater and why?
>>> 
>>> What's your favorite LNA and why?
>>> 
>>> Thank you in advance.
>>
>> Maybe ask persons who use AmSat (an amateur-satellite initiative).
>
>Joseph A. DiVerdi [1] hosted a last minute, surprise forum at our 
>Division's Ham Convention [2] last August. He brought along a 3U
>satellite to show off at his vendor's table.
>    Instead of thrusters, it spins a miniature momentum wheel. A de
>rigueur RTL-SDR and Raspberry Pi sat next to the satellite on his table.
>    Long story short, an EB144RK2M eggbeater will be used, along with a 
>cheap LNA module from ebay [3]. It ought to be easy enough to replace 
>the original LNA chip, if anyone knows of a superior LNA chip.
>
>Note.
>
>[1] <https://diverdi.colostate.edu/>
>[2] <https://wyohamcon.org>

>[3] <https://www.ebay.com/itm/198551314050?_trksid=p2332490.c101875.m1851>

Nice board, did you test it?

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#747799

Jan Panteltje <alien@comet.invalid> wrote:
>>"Don" <g@crcomp.net>wrote:
>>>Typo in original post corrected.
>>
>>C??il??n Niocl??s??n Glost??ir <thanks-to@taf.com> wrote:
>>> Don wrote:
>>>>
>>>> It seems best to start with the receiver. Here's one simple receiver
>>>> schematic:
>>>>
>>>> eggbeater antenna -> LNA -> LMR 200 -> RTL-SDR -> FreeBSD
>>>>
>>>> What's your favorite eggbeater and why?
>>>>
>>>> What's your favorite LNA and why?
>>>>
>>>> Thank you in advance.
>>>
>>> Maybe ask persons who use AmSat (an amateur-satellite initiative).
>>
>>Joseph A. DiVerdi [1] hosted a last minute, surprise forum at our
>>Division's Ham Convention [2] last August. He brought along a 3U
>>satellite to show off at his vendor's table.
>>    Instead of thrusters, it spins a miniature momentum wheel. A de
>>rigueur RTL-SDR and Raspberry Pi sat next to the satellite on his table.
>>    Long story short, an EB144RK2M eggbeater will be used, along with a
>>cheap LNA module from ebay [3]. It ought to be easy enough to replace
>>the original LNA chip, if anyone knows of a superior LNA chip.
>>
>>Note.
>>
>>[1] <https://diverdi.colostate.edu/>
>>[2] <https://wyohamcon.org>
>>[3] <https://www.ebay.com/itm/198551314050?_trksid=p2332490.c101875.m1851>
>
> Nice board, did you test it?

Good idea. It will be tested upon delivery.

Danke,

--
73, Don, WD7Q                                             veritas    _|_
                                                          liberabit   |
https://www.qsl.net/wd7q                                  vos         |

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#747801

On 9/14/2026 8:14 AM, Don wrote:
> It seems best to start with the receiver. Here's one simple receiver
> schematic:
> 
> eggbeater antenna -> LNA -> LMR 220 -> RTL-SDR -> FreeBSD
> 
> What's your favorite eggbeater and why?
> 
> What's your favorite LNA and why?
What led you to choosing RTL-SDR for the "muscle"?  Presumably,
you're only interested in receiving (?).

What sorts of broadcasts?

[I've been researching COTS offerings as it's simply not worth
the time to sort out the correct *design* criteria for these
devices]

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#747803

Am 14.09.26 um 17:14 schrieb Don:
> It seems best to start with the receiver. Here's one simple receiver
> schematic:
> 
> eggbeater antenna -> LNA -> LMR 220 -> RTL-SDR -> FreeBSD
> 
> What's your favorite eggbeater and why?
> 
> What's your favorite LNA and why?
For 432 it is this one
< 
https://www.flickr.com/photos/137684711@N07/48088857111/in/datetaken/lightbox/ 
  >

Why? because I made it to fit my likings.

Selectivity:
< 
https://www.flickr.com/photos/137684711@N07/48088857111/in/datetaken/lightbox/ 
 >

DL7APV (RIP) measured 0.25 dB noise figure, my own 8970B said 0.5 dB.
The difference could have to do with the bandwidth of the SAW filter
on 432 MHz vs. the bandwidth of the noise meter, and my 346C noise head
+ Rosenberger attenuator hasn't seen a cal lab for a long time.


You might be interested in these email reflectors:

https://groups.io/g/Moon-Net

https://groups.io/g/Amateur-DSN/


73,  Gerhard   DK4XP

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#747805

Am 16.09.26 um 15:37 schrieb Gerhard Hoffmann:

Oooohps, twice same pic.  Selectivity is the pic to the left.>
> 
> 73,  Gerhard   DK4XP
> 

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#747809

>Gerhard Hoffmann <dk4xp@arcor.de>wrote:
>>Am 14.09.26 um 17:14 schrieb Don:
>> It seems best to start with the receiver. Here's one simple receiver
>> schematic:
>> 
>> eggbeater antenna -> LNA -> LMR 220 -> RTL-SDR -> FreeBSD
>> 
>> What's your favorite eggbeater and why?
>> 
>> What's your favorite LNA and why?
>For 432 it is this one
>< 
>https://www.flickr.com/photos/137684711@N07/48088857111/in/datetaken/lightbox/ 
>  >
>
>Why? because I made it to fit my likings.
>
>Selectivity:
>< 
>https://www.flickr.com/photos/137684711@N07/48088857111/in/datetaken/lightbox/ 
> >
>
>DL7APV (RIP) measured 0.25 dB noise figure, my own 8970B said 0.5 dB.
>The difference could have to do with the bandwidth of the SAW filter
>on 432 MHz vs. the bandwidth of the noise meter, and my 346C noise head
>+ Rosenberger attenuator hasn't seen a cal lab for a long time.
>
>
>You might be interested in these email reflectors:
>
>https://groups.io/g/Moon-Net
>
>https://groups.io/g/Amateur-DSN/
>
>
>73,  Gerhard   DK4XP

I have this for 2.4 GHz:
 https://panteltje.nl/pub/spectrian_2.4-GHz_linear_top_view_IMG_4576.JPG

Low power driver:
 https://panteltje.nl/pub/1W_PA_400_to_2700MHz_PCB_view_IXIMG_0051.JPG

And a bunch of Yagi antennas:
 https://panteltje.nl/panteltje/raspberry_pi_satellite_tracker/yagi_2.4GHz_25dB_IMG_3984.JPG
  Controlled by some RC servos but not in use atm:
  https://panteltje.nl/panteltje/raspberry_pi_satellite_tracker/

Just experiments...

A lot more stuff, not really active on ham RF atm.

What also makes a very good receive antanna are the old TV antenna racks:
 https://www.asat.nl/outdoor-antenna-12-5-db
  TRIAX DIGI Grid UHF antenna (LTE 700)
  The antenna is designed to receive a ground -based digital TV broadcast in
  the frequency range  470 ... 694 MHz (channels 21-48).
Good screening from the back, used it for many years for many different things.

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#747814

Am 16.09.26 um 16:25 schrieb Jan Panteltje:

> 
> I have this for 2.4 GHz:
>   https://panteltje.nl/pub/spectrian_2.4-GHz_linear_top_view_IMG_4576.JPG

Do you have any info on that Spectrian stuff?

Methinks I have the same but can't find the info anymore.

https://www.flickr.com/photos/137684711@N07/53498717513/in/datetaken/lightbox/
 >>
 >>
 >> 73,  Gerhard   DK4XP

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#747820

>Gerhard Hoffmann <dk4xp@arcor.de>wrote:
>>Am 16.09.26 um 16:25 schrieb Jan Panteltje:
>
>> 
>> I have this for 2.4 GHz:
>>   https://panteltje.nl/pub/spectrian_2.4-GHz_linear_top_view_IMG_4576.JPG
>
>Do you have any info on that Spectrian stuff?
>
>Methinks I have the same but can't find the info anymore.
>
>https://www.flickr.com/photos/137684711@N07/53498717513/in/datetaken/lightbox/

I bought it on ebay, March 2019 says the time of this file.
Time flies :-)

Below is what I have saved from the seller,
the ebay link below no longer works, seller is still on ebay (google KI4NPV)?


From:
 https://www.ebay.com/itm/75W-Spectrian-Linear-RF-Amplifier-Board-2-3-2-35-GHz-18dBg-24-26V-/223448095832?oid=221556214361

ebay.com/itm/221556214361

Picture Information
75W-Spectrian-Linear-RF-Amplifier-Board-2-3-2-35-GHz-18dBg-24-26V

Details about  75W Spectrian Linear RF Amplifier Board 2.3-2.35 GHz 18dBg 24/26V

This is a 75W linear amplifier board as removed from a new Spectrian power amplifier which is optimized for 2.30-2.35GHz but is also useful up to 2.45GHz at reduced power an gain.
This amplifier board does not require any tuning for use on the ham band! Required supply voltage is 24-26Vdc at about 17A.
Input drive required for 75W output power is 1.25W.
Power gain is 18dB.
Saturated power is 80W+.
This is the final Rev.
for this board design (Rev A)which has larger plated through holes and the holes have been sealed so the silicon grease does not come through the top side when bolting the board down to the heat-sink.
The earlier rev.
were all number revs with open vias.
I sell the older "number rev boards" at a lower price on other auctions.
The sweep photo shows one of these amps putting out 80W with about one watt input at 2304GHz.
The output (CH1) reference is set for 100W (50dBm)with a scale factor of 5dBm/division.
Channel 2 is the input power with it's reference set for 10W (40dBm)with 5dBm/division.
Sweep is from 2.2-2.6GHz with 50MHz/ division.
Looking at the output plot you will see the level 1dB down from 50dBm or 80 Watts and the input 9.4dBm down 40 = 30.6dBm, slightly over one watt.
Looking at 2450 MHz you can see the output is down 4dB form 50 - 46dBm = 40W.
Note the preamp I am driving this PA with is not linear with frequency over this full range as indicated by channel 2.
Circuit board is on an integral .062" solid copper heat spreader.
Both the board upper surface and the heat spreader surface are heavy gold plated.
Board needs to be mounted on heat-sink using Silicon grease and 7ea.
4-40 screws in existing holes.
RF input and outputs are 50 ohm strip-line and will butt up to a standard SMA or N launch connector.
Good quality SMA connectors are rated to 400W at 2GHz and work very well for this amp.
The XRF286 Lateral Mosfets used on this board can handle a 10:1 VSWR at full power so isolators are not required.
Board dimensions are 2.25" x 5.9".   57.15 x 149.86 mm
Weight is 6 ounces.
DC connector pin-out.
1, Temperature output = 10MV/ degree F.
2, PTT = +12V To enable all 3 power FETs.
3, Drain current monitor for Q1.
1 volt out/amp of drain current.
4, Drain current monitor for Q2.
1 volt out/amp of drain current.
5, Ground.
6-10 are no connection.
(I also have some of the complete 180W Spectrian amplifiers available and will
start a fixed price auction for you by request.
Please call [phone removed by eBay] to request an auction if you don't see one
currently running.)

Florida buyers must add 7% (or actual amount for your county) sales tax or mail me a signed photocopy of your Florida Resale Certificate with your payment! I do combine auction winnings when ever possible to save buyers money.
I do ask that buyers help keep track of any auction shipments they want to combine and email me for a total when they are ready.
Fixed Priority S&H quoted prices are for 50 USA states.
International Bidders pay actual S&H.
Good luck bidding! KI4NPV [phone removed by eBay]

Power consumption 17 x 25 = 425 W
heat 425 - 75 =  (17 * 25) - 75  = 350 W
Junction temp is 100? C ?
Rth = 100 / 350 = .285714 C/w

That leads to this for heatsink:
https://www.conrad.nl/p/profielkoellichaam-03-kw-l-x-b-x-h-150-x-75-x-62-mm-fischer-elektronik-la-6-150-al-166111
 Profielkoellichaam 0.3 K/W (l x b x h) 150 x 75 x 62 mm Fischer Elektronik LA 6 150 AL
 Koellichaam met hoog vermogen
  Artikelnummer: 166111
  Fabrikantnummer: 10015838
  EAN: 4016138077872

Met een bijzonder effectieve warmteafvoer door de geoptimaliseerde holle ribben.
Translated from Dutch:
 Very effective heat transfer because of hollow ribs.
    Garantee: minimaal 2 jaar
    Make: Fischer Elektronik
--------------------------

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#747821

Am 16.09.26 um 19:59 schrieb Jan Panteltje:
>> Gerhard Hoffmann <dk4xp@arcor.de>wrote:
>>> Am 16.09.26 um 16:25 schrieb Jan Panteltje:
>>

Thanks!  :-)

I'm moving to a smaller qth for retirement and my
house... well, entropy never sleeps.

Cheers, Gerhard

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#747822

On Wed, 16 Sep 2026 14:25:34 GMT, Jan Panteltje <alien@comet.invalid>
wrote:

>>Gerhard Hoffmann <dk4xp@arcor.de>wrote:
>>>Am 14.09.26 um 17:14 schrieb Don:
>>> It seems best to start with the receiver. Here's one simple receiver
>>> schematic:
>>> 
>>> eggbeater antenna -> LNA -> LMR 220 -> RTL-SDR -> FreeBSD
>>> 
>>> What's your favorite eggbeater and why?
>>> 
>>> What's your favorite LNA and why?
>>For 432 it is this one
>>< 
>>https://www.flickr.com/photos/137684711@N07/48088857111/in/datetaken/lightbox/ 
>>  >
>>
>>Why? because I made it to fit my likings.
>>
>>Selectivity:
>>< 
>>https://www.flickr.com/photos/137684711@N07/48088857111/in/datetaken/lightbox/ 
>> >
>>
>>DL7APV (RIP) measured 0.25 dB noise figure, my own 8970B said 0.5 dB.
>>The difference could have to do with the bandwidth of the SAW filter
>>on 432 MHz vs. the bandwidth of the noise meter, and my 346C noise head
>>+ Rosenberger attenuator hasn't seen a cal lab for a long time.
>>
>>
>>You might be interested in these email reflectors:
>>
>>https://groups.io/g/Moon-Net
>>
>>https://groups.io/g/Amateur-DSN/
>>
>>
>>73,  Gerhard   DK4XP
>
>I have this for 2.4 GHz:
> https://panteltje.nl/pub/spectrian_2.4-GHz_linear_top_view_IMG_4576.JPG
>
>Low power driver:
> https://panteltje.nl/pub/1W_PA_400_to_2700MHz_PCB_view_IXIMG_0051.JPG
>
>And a bunch of Yagi antennas:
> https://panteltje.nl/panteltje/raspberry_pi_satellite_tracker/yagi_2.4GHz_25dB_IMG_3984.JPG
>  Controlled by some RC servos but not in use atm:
>  https://panteltje.nl/panteltje/raspberry_pi_satellite_tracker/
>
>Just experiments...
>
>A lot more stuff, not really active on ham RF atm.
>
>What also makes a very good receive antanna are the old TV antenna racks:
> https://www.asat.nl/outdoor-antenna-12-5-db
>  TRIAX DIGI Grid UHF antenna (LTE 700)
>  The antenna is designed to receive a ground -based digital TV broadcast in
>  the frequency range  470 ... 694 MHz (channels 21-48).
>Good screening from the back, used it for many years for many different things.
>

https://www.dropbox.com/scl/fi/ekj2c70spwogmwuo63u5q/MoonBounce.JPG?rlkey=taobwn5osfptklqmyil8kytma&raw=1

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#747823

Am 16.09.26 um 20:31 schrieb john larkin:

> 
> https://www.dropbox.com/scl/fi/ekj2c70spwogmwuo63u5q/MoonBounce.JPG?rlkey=taobwn5osfptklqmyil8kytma&raw=1
> 

Back when we were students at the Technical Univ Berlin we founded
there the ham radio club DK0TU and had a club station that was good
enough for earth-moon-earth on 144 MHz. It was fun to hear one's
own echoes from the moon after 2.5 seconds.

4 of the group bought a residual farm after re-unification, north-west
of Berlin in the middle of nowhere. EMC-wise completely silent.

Bernd, DL7APV was the biggest activist.
His antenna can be seen here  <  https://www.dl7apv.de/    >
He's the one who measured my pre-amp.

Unfortunately, hie died shortly after retirement. We miss him.

@Don:   You can get the Altium files if you want.

Gerhard, DK4XP

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#747824

Gerhard Hoffmann <dk4xp@arcor.de> wrote:
> Am 16.09.26 um 20:31 schrieb john larkin:
>
>>
>> https://www.dropbox.com/scl/fi/ekj2c70spwogmwuo63u5q/MoonBounce.JPG?rlkey=taobwn5osfptklqmyil8kytma&raw=1
>>
>
> Back when we were students at the Technical Univ Berlin we founded
> there the ham radio club DK0TU and had a club station that was good
> enough for earth-moon-earth on 144 MHz. It was fun to hear one's
> own echoes from the moon after 2.5 seconds.
>
> 4 of the group bought a residual farm after re-unification, north-west
> of Berlin in the middle of nowhere. EMC-wise completely silent.
>
> Bernd, DL7APV was the biggest activist.
> His antenna can be seen here  <  https://www.dl7apv.de/    >
> He's the one who measured my pre-amp.
>
> Unfortunately, hie died shortly after retirement. We miss him.
>
> @Don:   You can get the Altium files if you want.

Thank you! Please forward your files and/or links to me at wd7q@qsl.net

During its forum the Deep Space Exploration Society presented a brief
video showing someone's granddaughter speaking into a microphone and
hearing her own voice a few seconds later after an EME bounce. The
antenna at the facility is a rock sold beast built in the 1960s, IIRC:

<https://dses.science/2018/12>

Danke,

--
73, Don, WD7Q                                             veritas    _|_
                                                          liberabit   |
https://www.qsl.net/wd7q                                  vos         |

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#747825

On Wed, 16 Sep 2026 21:28:39 +0200, Gerhard Hoffmann <dk4xp@arcor.de>
wrote:

>Am 16.09.26 um 20:31 schrieb john larkin:
>
>> 
>> https://www.dropbox.com/scl/fi/ekj2c70spwogmwuo63u5q/MoonBounce.JPG?rlkey=taobwn5osfptklqmyil8kytma&raw=1
>> 
>
>Back when we were students at the Technical Univ Berlin we founded
>there the ham radio club DK0TU and had a club station that was good
>enough for earth-moon-earth on 144 MHz. It was fun to hear one's
>own echoes from the moon after 2.5 seconds.
>
>4 of the group bought a residual farm after re-unification, north-west
>of Berlin in the middle of nowhere. EMC-wise completely silent.
>
>Bernd, DL7APV was the biggest activist.
>His antenna can be seen here  <  https://www.dl7apv.de/    >
>He's the one who measured my pre-amp.
>
>Unfortunately, hie died shortly after retirement. We miss him.
>
>@Don:   You can get the Altium files if you want.
>
>Gerhard, DK4XP

That pic is from 1946, and they used tubes and point-contact diode
mixers. Mediocre noise figures. I guess the moon is actually a pretty
big reflector.

Being spherical, it must scatter the reflection over half the
universe.

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#747826

Am 16.09.26 um 22:18 schrieb john larkin:

> That pic is from 1946, and they used tubes and point-contact diode
> mixers. Mediocre noise figures. I guess the moon is actually a pretty
> big reflector.
> 
> Being spherical, it must scatter the reflection over half the
> universe.

Path loss is abt. 235 dB IIRC, give or take some minor deviations
for exact frequency and current moon position in the elliptical
orbit.

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#747832

>Gerhard Hoffmann <dk4xp@arcor.de>wrote:
>>Am 16.09.26 um 20:31 schrieb john larkin:
>
>> 
>> https://www.dropbox.com/scl/fi/ekj2c70spwogmwuo63u5q/MoonBounce.JPG?rlkey=taobwn5osfptklqmyil8kytma&raw=1
>> 
>
>Back when we were students at the Technical Univ Berlin we founded
>there the ham radio club DK0TU and had a club station that was good
>enough for earth-moon-earth on 144 MHz. It was fun to hear one's
>own echoes from the moon after 2.5 seconds.
>
>4 of the group bought a residual farm after re-unification, north-west
>of Berlin in the middle of nowhere. EMC-wise completely silent.
>
>Bernd, DL7APV was the biggest activist.
>His antenna can be seen here  <  https://www.dl7apv.de/    >

Impressive!

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#747813

Gerhard Hoffmann <dk4xp@arcor.de> wrote:
> Am 14.09.26 um 17:14 schrieb Don:
>> It seems best to start with the receiver. Here's one simple receiver
>> schematic:
>>
>> eggbeater antenna -> LNA -> LMR 200 -> RTL-SDR -> FreeBSD
>>
>> What's your favorite eggbeater and why?
>>
>> What's your favorite LNA and why?
> For 432 it is this one
> <https://www.flickr.com/photos/137684711@N07/48088857111/in/datetaken/lightbox/>
>
> Why? because I made it to fit my likings.
>
> Selectivity:
> <
> <https://www.flickr.com/photos/137684711@N07/48088857111/in/datetaken/lightbox/>
>
>
> DL7APV (RIP) measured 0.25 dB noise figure, my own 8970B said 0.5 dB.
> The difference could have to do with the bandwidth of the SAW filter
> on 432 MHz vs. the bandwidth of the noise meter, and my 346C noise head
> + Rosenberger attenuator hasn't seen a cal lab for a long time.
>
>
> You might be interested in these email reflectors:
>
> https://groups.io/g/Moon-Net
>
> https://groups.io/g/Amateur-DSN/

Your custom LNA is perfect! It inspires me to make my own LNA, after
my nascent satellite station becomes fully functional for both
transmission and reception. For the time being my strategy is to 
minimize my learning curve.
    It's supposedly possible to run DC over coax to the LNA. But
again, to minimize my learning curve, a separate outdoor DC cable
will be used instead.
    Thank you for sharing the email reflectors. A Deep Space Exploration
Society <https://dses.science/> spokesman also showed up at my 
Divisional ham convention.

Danke,

--
73, Don, WD7Q                                             veritas    _|_
                                                          liberabit   |
https://www.qsl.net/wd7q                                  vos         |

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