M31 Radio Map Green Bank 20m RT 130325
My first observations with the 20m radio telescope at Green Bank.
Andy
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Hello Folks
I am looking for help in making regular meteor observations using the UK meteor radar system. See the live stream at :-
We are seeing some very interesting effects from the network of ( currently ) 4 receiving sites. I am unable to make systematic observations on a regular basis due to ongoing commitments on this project and other matters but the system is available to all to make a contribution.? I can give some guidance? on what to look for on a personal basis so if you are interested and available please get in touch.
All the best Brian for the UK meteor radar project.
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The Hidden Wonders of the Sky
Andrew Thornett, March 2025
Why, oh why, can they not see –
The wonder of a starry sky –
Seen with starlight not visible without,
The wonders of the modern world.
Beacons blink in cosmic song,
Billions whisper all night long,
Between the voids where giants spin,
Bringing secrets deep within.
Celestial signals, faint yet bright,
Calling from the edge of sight,
Caught by aerials tuned with care,
Cracking codes from distant air.
Daring pulses race through space,
Dancing waves in endless chase,
Drifting, shifting, bending light,
Drawing minds to scale their height.
Echoes trace a past unknown,
Eons speaking, softly shown,
Eager ears and patient hands
Extract what deep time still demands.
Far beyond the eye’s own reach,
Frequencies in silent speech
Find their way to those who dare
Follow trails through frozen air.
Gazing upward, lost in thought,
Galaxies with wonder fraught,
Grains of truth in static lie—
Grasp them, question, ask them why!
Would they listen? Would they care?
Why, oh why, don’t they just stare?
What is lost if minds stay blind
When the universe calls—unkind?
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Re: 20m radio telescope at Greenbank
I used to pay for access to Siding
Spring Observatory scopes via and it
was a very useful, if expensive, way to avoid my local light
pollution issues for optical astronomy. I didn't know there were
options to get time on professional radio instruments, very
interesting.?
There are some small radiotelescopes
with remote access, but they are limited size and frequency range.
and
are two I'm aware of.
I think
were working on an interferometer interface unit for their
dishes/drives/receivers/spectrometers, that could get interesting,
at least for folks with deep pockets.? I'd love to find some other
folks within 10-200 km of my location in East Yorkshire who would
like to try some VLBI linking of amateur radiotelescopes for
pulsar observations. The technical contraints are challenging to
put it mildly!
I advise choosing your life partner
VERY carefully, selecting only those who will be entirely
accepting of mad antenna projects in the garden. My late wife was
totally chilled about all of my skyhook projects, never even
raising an eyebrow in the 37 years we were together, despite
dishes, 100ft masts, yagi arrays and 200 metre long wire antenna
systems and a couple of miles of ground screen for VLF.
Anyone else know of subscription deals
for similar radio telescopes, preferably with a range of
frequencies suited to pulsar observations (2/4/8 GHz pref)
Neil
On 09/03/2025 15:00, Andrew Thornett
via groups.io wrote:
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I have just registered as user of the 20m
radio telescope at Greenbank Observatory as part of my
membership of SARA – I am very excited as my wife won’t accept
a 20m dish in our garden, for some unknown reason – she is
unreasonable like that!
Perhaps BAA RAG should see if they can get
access to a professional dish in the UK for members to get
access to?
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20m radio telescope at Greenbank
I have just registered as user of the 20m radio telescope at Greenbank Observatory as part of my membership of SARA – I am very excited as my wife won’t accept a 20m dish in our garden, for some unknown reason – she is unreasonable like
that!
Perhaps BAA RAG should see if they can get access to a professional dish in the UK for members to get access to?
Andy
|
Now that we have
receivers for the UK Meteor radar project at four different
locations
we are seeing some interesting results and would very much
appreciate
some systematic manual observations of meteor echoes using the live
stream at
. The observations could take as little as ten minutes ideally
repeated twice per day. Even observations made for just one day
would
help but 2 observation sessions per day repeated for a few days
would
be even more useful.
If you are able to
help
please contact me and I'll explain exactly what we are looking
for.
There is a description
of how to use the live display at
which you will find in the resources / documents section of the
project web pages at
.
Brian
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The planning for EuCARA25 in September is going well, interest is mounting.
We are now giving opportunity for the amateur community to contribute.?
?
Please contact me if:
- You want a time slot to share Observations or instrumentation.
- You have a poster to add to those already submitted.?
- You want to bring along kit to demonstrate.
?
Visit ???http:/eucara.org??? for registration and further details.??
--
???? Paul Hearn? ???? ? paul@...? ???? ?RA Section Director? ???
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Analysing my spare Nooelec SAWBird H1 LNAs to check whether performance varies across units
Please see following link for my analysis of my spare SAWBirds using NanoVNA.
Andy
?
?
?
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Testing Nooelec SAWBird H1 LNA
These LNAs are designed to pass 1420dB +/- 30MHz, and the product sheet states they produce 40dB amplification – this analysis with a NanoVNA supports that – S21 Logmag = 0.15dB + 40dB attenuation in the circuit (the gold device in series
with LNA is a variable RF attenuator set to 40dB) = 40.15dB, and a reasonably flat top to the curve in the area of 1420MHz as well.
…..so this Nooelec is good…..now to test the other ones I have!
Andy
?
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Hello Folks
We now have 5
operational receivers in the UK Meteor radar network which can be
viewed at
. We have also made more than 48 hours of recordings of the full
bandwidth data from all 5 receivers . During this period, meteor
events have been occurring at a rate of about 2 per minute so
there's
plenty of data to work with and we will be making more recordings
in
the future especially around the time of major meteor showers.
These data are
available to download along with some contemporaneous notes and
manual observations of the first hour of recording as a guide.
It would be of great
interest if there is anyone out there who could take this data and
work out how to input it to software such as Spectrum Lab or SDR
Console for analysis and display. To find out more go to the
project web site at:-
to find the recorded data along with guiding notes and description
of the data and timing formats.
Brian
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RAZoom March 7th. Postponed.
Alex has asked us to reschedule, so there will be no RAZoom on Friday 7th March
Project HLine3D : A Beginners Guide to Hydrogen Emission Line Microwave Radio Astronomy
Alex Pettit Winter Springs, Fla
?
Coming up……
?
Friday 4th April 19:30 (18:30 UTC)
Open forum...., so far, we have two presentations, If you have observations or Instrumentation you want to share with the community let me know. The running order will be published mid-March.
?
Friday 2nd May 19:30 (18:30 UTC)
Binary Stars and Stellar Cannibalism
Dr. Noel Castro-Segura University of Warwick
?
Friday 6th June? 19:30 (19:30 UTC)?
Observing Magnetic Fields in space generally, using Micro-wave Radio Observations
Prof. Derek Waed-Thompson
--
???? Paul Hearn? ???? ? paul@...? ???? ?RA Section Director? ???
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Today's echo of the
day
shows examples of some of the properties you can observe from the
UK
Meteor Radar project live stream at .
The first echo. At the
bottom of the screens was seen strongly by the Norman Lockyer
receiver ( No 1, top left) and by both the NW Hampshire receivers,
(
Nos 4 and 5, Bottom row) but not by the Armagh receiver (No 2).
This
shows that this echo was highly directional and either not
strongly
linearly polarised or, more likely, that it was linearly polarised
but aligned equally for both vertical and horizontal antennas
perhaps
at about 45 degrees to both. The next very small echo was only
seen
by receivers 4 and 5, much more strongly with horizontal
polarisation
than with vertical polarisation. The next echo immediately above
the
last is also much stronger at the horizontally polarised antenna (
receiver 4 ) indicating that it is strongly linearly polarised. It
is also directional as receiver 2, Armagh didn't “see” it. This
head echo has another interesting feature, the pulsing effect.
This
is caused by interference patterns resulting from the ( multi wave
)
length of the ionised region “moving across” the receiving
antenna as the meteor travels across the sky.
Other echoes are seen
on the NW Hampshire Horizontally polarised display but not others
due
mainly to linear polarisation and directionality. Receivers 3 and
6
have been edited from this image as they are not in service. The
Blairgowrie receiver No 3, is streaming data but as yet has no
antenna, poor weather having delayed it's erection.
Brian
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Re: Aerials for meteor observing 143.048MHz
Thanks to everyone for their comments on aerials for meteor scatter
Andy
Sent from
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Andrew T
?If I am understanding your query correc, then the aerial design was known as a Moxon arial
A Moxon antenna is?a type of directional antenna, often referred to as a "Moxon rectangle," which is a simple, two-element parasitic array design with a rectangular shape, where the ends of the elements are bent towards each
other, creating a compact antenna with good gain and a high front-to-back ratio, making it popular among amateur radio enthusiasts due to its ease of construction and performance in limited space situations;?it was developed by Les Moxon (G6XN). ?
Key points about Moxon antennas:
Hope this?is helpful
Norman.
On Sat, Feb 22, 2025 at 10:05?PM Andrew Thornett via
<andrew= [email protected]> wrote:
Thanks Chris.
?
Years ago, there was a different off the shelf aerial used to be commonly used – I can’t remember what it used to be called.
?
Andy
?
?
I use a homemade 3 element Yagi, based on Paul Hyde's one from 'Sky at Night' magazine in 2014 and currently available on the BAA website via:
Chris
On 22/02/2025 16:20, Andrew Thornett via wrote:
What are the different types of aerials recommended for 143Mhz meteor scatter? I would like a list to add to my talk. I use a Moxon but I know there are other types
--
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Re: Aerials for meteor observing 143.048MHz
Andrew T ?If I am understanding your query correc, then the aerial design was known as a Moxon arial
A Moxon antenna is?a type of directional antenna, often referred to as a "Moxon rectangle," which is a simple, two-element parasitic array design with a rectangular shape, where the ends of the elements are bent towards each other, creating a compact antenna with good gain and a high front-to-back ratio, making it popular among amateur radio enthusiasts due to its ease of construction and performance in limited space situations;?it was developed by Les Moxon (G6XN). ?Key points about Moxon antennas: Hope this?is helpful
Norman.
On Sat, Feb 22, 2025 at 10:05?PM Andrew Thornett via <andrew= [email protected]> wrote:
Thanks Chris.
?
Years ago, there was a different off the shelf aerial used to be commonly used – I can’t remember what it used to be called.
?
Andy
?
?
I use a homemade 3 element Yagi, based on Paul Hyde's one from 'Sky at Night' magazine in 2014 and currently available on the BAA website via:
Chris
On 22/02/2025 16:20, Andrew Thornett via wrote:
What are the different types of aerials recommended for 143Mhz meteor scatter? I would like a list to add to my talk. I use a Moxon but I know there are other types
|
Re: Aerials for meteor observing 143.048MHz
HLP-6 50MHz 6M Halo Loop Folded Dipole Antenna?
Andrew, here are 4 currently in use antennas I have for radio meteor obs on 143.05MHz
?
?
?
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Re: Aerials for meteor observing 143.048MHz
Andrew, here are 4 currently in use antennas I have for radio meteor obs on 143.05MHz
?
?
?
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Re: Aerials for meteor observing 143.048MHz
I've used a quadrifilar helix like the weather satellite versions intended for 137 MHz satellites. Also a 3 element cubical quad and a 3 element crossed yagi in X format, with separate receivers for polarisation diversity.
I tried tilting the QFH towards Dijon, but it didn't make much difference. I also use a 9 element yagi, but it is way too sharp. The extra gain does help pull out really weak echoes, or when I'm tracking the GRAVES echoes from the International Space Station.
HB9CV and Yagis with a gamma match have the disadvantage that they need a tuning capacitor, which is tough to weatherproof, even if you replace the variable capacitor with a fixed one of the correct value. The HB9CV is a variation on the ZL Special. Neil
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On 22 Feb 2025, at 22:20, Andrew Thornett via groups.io <andrew@...> wrote:
?
Found it now – we all used to use
HB9CV Aerials. They seem to have gone out of fashion for meteor scatter from Graves now – don’t know why – perhaps someone can tell me?
Andy
?
?
Thanks Chris.
?
Years ago, there was a different off the shelf aerial used to be commonly used – I can’t remember what it used to be called.
?
Andy
?
?
I use a homemade 3 element Yagi, based on Paul Hyde's one from 'Sky at Night' magazine in 2014 and currently available on the BAA website via:
Chris
On 22/02/2025 16:20, Andrew Thornett via groups.io wrote:
What are the different types of aerials recommended for 143Mhz meteor scatter? I would like a list to add to my talk. I use a Moxon but I know there are other types
|
Re: Aerials for meteor observing 143.048MHz
Found it now – we all used to use
HB9CV Aerials. They seem to have gone out of fashion for meteor scatter from Graves now – don’t know why – perhaps someone can tell me?
Andy
?
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Show quoted text
From: [email protected] <[email protected]>
On Behalf Of Andrew Thornett via groups.io
Sent: 22 February 2025 22:06
To: [email protected]
Subject: Re: [baa-rag] Aerials for meteor observing 143.048MHz
?
Thanks Chris.
?
Years ago, there was a different off the shelf aerial used to be commonly used – I can’t remember what it used to be called.
?
Andy
?
?
I use a homemade 3 element Yagi, based on Paul Hyde's one from 'Sky at Night' magazine in 2014 and currently available on the BAA website via:
Chris
On 22/02/2025 16:20, Andrew Thornett via groups.io wrote:
What are the different types of aerials recommended for 143Mhz meteor scatter? I would like a list to add to my talk. I use a Moxon but I know there are other types
|
Re: Aerials for meteor observing 143.048MHz
Thanks Chris.
?
Years ago, there was a different off the shelf aerial used to be commonly used – I can’t remember what it used to be called.
?
Andy
?
toggle quoted message
Show quoted text
From: [email protected] <[email protected]>
On Behalf Of Chris Holt via groups.io
Sent: 22 February 2025 16:37
To: [email protected]
Subject: Re: [baa-rag] Aerials for meteor observing 143.048MHz
?
I use a homemade 3 element Yagi, based on Paul Hyde's one from 'Sky at Night' magazine in 2014 and currently available on the BAA website via:
Chris
On 22/02/2025 16:20, Andrew Thornett via groups.io wrote:
What are the different types of aerials recommended for 143Mhz meteor scatter? I would like a list to add to my talk. I use a Moxon but I know there are other types
|
Re: Aerials for meteor observing 143.048MHz
I use a homemade 3 element Yagi, based on Paul Hyde's one from
'Sky at Night' magazine in 2014 and currently available on the BAA
website via:
Chris
On 22/02/2025 16:20, Andrew Thornett
via groups.io wrote:
toggle quoted message
Show quoted text
What are the different types of aerials
recommended for 143Mhz meteor scatter? I would like a list to
add to my talk. I use a Moxon but I know there are other types
Andy
|
Paul Hearn
