15-Day Drift Scan at Dec +40 Degrees from my 2.4 m Dish

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Ayushman Tripathi

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Apr 19, 2026, 10:02:42 AMApr 19
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Hi,

I managed to resolve the artifacts generated by the baseline correction in my script.

Here are the plots with this week’s data included.

I’ll also adjust some observation settings to evaluate the impact on the results.

Also, for my smaller dish, I’ve added a steel mesh around it and will share its data.

Thanks.
151.png152.png158.png157.png156.png155.png

f1d45a3d-2f32-44ff-bbc7-cd4ac53108f0.jpeg

Alex P

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Apr 19, 2026, 10:22:59 AMApr 19
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Excellent results :)

What techniques did you implement ?

Thanks,
Alex

Ayushman Tripathi

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Apr 19, 2026, 5:05:51 PMApr 19
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Hi Alex,

Here's the pipeline method I used:

1. Per-observation calibration. Each 5-minute scan is recorded raw with Airspy Mini (3 MHz span, 1024 FFT bins at 1420.406 MHz). VIRGO processes it against a separate cold-sky calibration scan: it divides the observation by the cold-sky spectrum, then normalizes it by the noise standard deviation in the line-free channels to put everything in signal-to-noise (SNR) units and finally applies a median filter in frequency. The output is one "filtered" spectrum per scan.

2. Wing-linear residual. I measure the remaining slope and offset using only the true line-free wings and then subtract that linear baseline from the whole spectrum.

3. VLSR correction + RA stacking. Each observation is Doppler-shifted onto a common LSR velocity grid, then observations are binned by RA (0.10 h bins) and median-combined across all sidereal loops.

I'm constantly experimenting with these techniques to improve the pipeline.

Thanks.

b alex pettit jr

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Apr 19, 2026, 6:29:51 PMApr 19
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Hello Ayushman,

Sounds very close to my sequence, except I subtract vs divide as the shifts are not gain but environment amplitude shift related.
And I use simple mX+b slope correction ..

I probably will not incorporate VLSR correction in the HL3D code.

Inline image
Thanks,
Alex
============================================

Ayushman Tripathi

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Apr 20, 2026, 6:28:23 PMApr 20
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Hi Alex,

Yes, I’m still trying to improve it. I can also try HL3D’s plotting on the same collected data later this week and will share the results.

Thanks.

Sent from my iPad

b alex pettit jr

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Apr 20, 2026, 7:02:27 PMApr 20
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Attached is an example of the IFavg format for *.txt Input  and the *.csv output

Inline image

*.CSV format as required for Rinearn Graphics 2D / 3D .

A1 Blank  
B1 ....  (RA) Time Hrs
ColA = Freq

Ampl Field dB re cold sky

Inline image

Thanks,
Alex


D40_RA1800_0001.txt
6Hrs_CSN_mxb_dBScaled.csv

Ayushman Tripathi

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Apr 24, 2026, 5:51:08 PMApr 24
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Hi Alex,

I wrote a rough converter from my pipeline output to the Rinearn CSV format you shared.

Here are some plots I generated using Rinearn Graphics.

The converter might still have a few bugs, I'll try to improve this along with my processing pipeline.

Thanks.

Screenshot From 2026-04-24 17-30-07.png
Screenshot From 2026-04-24 17-26-33.png
Screenshot From 2026-04-24 17-27-47.png

Screenshot From 2026-04-24 17-33-42.png
Screenshot From 2026-04-24 17-37-53.png

b alex pettit jr

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Apr 24, 2026, 6:47:31 PMApr 24
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On Friday, April 24, 2026 at 05:51:19 PM EDT, Ayushman Tripathi <ayushmantr...@gmail.com> wrote:

Hello Ayushman,

>>>  Well I am Impressed   !!   EmojiEmoji


Very small adjustments to the "Range" Z  min settings can make major changes in the appearance of the plots
example : auto scale set Z min @ -0.2543    changing to -0.15 or -0.35 might improve the plot ( OR More, of course )
Inline image

=====================================================

Attached are a few plot formats to try ..
Copy them to  the Rinearn3D directory tree folder :  Rinearn3DQuickSetting


(  use Wordpad, etc to view & edit the  *.ini   text files )

Inline image

This is a scan @ Dec +60 deg with the HC_Blue   w/ my 1.2m system 
Inline image

Regards,
Alex P
========================================================================
========================================================================
GradiationScaleDark2.ini
True-Zaxis.ini
Z_HighContrast01.ini
HC_Blue.ini
Message has been deleted

b alex pettit jr

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Apr 24, 2026, 8:49:41 PMApr 24
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On Friday, April 24, 2026 at 07:31:30 PM EDT, 'b alex pettit jr' via Society of Amateur Radio Astronomers <sara...@googlegroups.com> wrote:


@ Dec +40

HC_blue
Inline image


Ayushman Tripathi

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Apr 25, 2026, 10:10:42 AMApr 25
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Hi Alex,

Here are some plots using the formats you shared: HC_blue, True-Zaxis, etc.

Your scan at Dec +60 DEG looks very nice. My dish is currently pointed at Dec +40, next time I visit, I'll try Dec +60. I had to put the dish away from the city, it's near a forest with very little RFI, and it sends data back over cellular internet. I put the Raspberry Pi, cellular modem, UPS, etc. in a metal box, the only thing outside the box is the antenna for the cellular router. No Wi-Fi is used, everything runs over an Ethernet cable.

Thanks.
graph3d2501.png

graph3d2502.png

graph3d2503.png

Screenshot From 2026-04-25 09-32-26.png

b alex pettit jr

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Apr 25, 2026, 1:03:42 PMApr 25
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Hello Ayushman,

Thanks. Not sure Rinearn is any improvement over your software, but its nice we can Both Plot using the same format !

Regarding the Gradient_Color_List, the colors are in Quads RGBI :  Red_Green_Blue_Intensity ;  ......
You can change the list to just a few or extend the list of color quads and the software will blend the transitions.

standard
Inline image

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=================================================================================

A suggestion : Verify the "dB" scaling of your data .

Use a 50 ohm terminated LNA as the noise source and impose several steps of attenuation into the SDR,
process by your Software and verify there is consistency .. 

Adding a fixed Attenuator on the input to the SDR seems to improve the test results - 
probably because it creates a constant 50 ohm resistive Z on the SDR input vs what would normally be done :
 comparing attenuated signals against a directly connected LNA<>SDR for '0'dB reference.

Inline image
Your values seem a bit high ..  
I've found 3dB over cold sky  is a typical max value regardless of dish size ... even to 12 meters in diameter !

Alex
==========================================================

Ayushman Tripathi

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Apr 25, 2026, 5:27:22 PMApr 25
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Hi Alex,

Yes this is great, now we can use same plot format and compare them easily.
I’ll experiment with color gradients.

Regarding dB scaling, I’ll check and confirm/correct that soon.

Thanks
Sent from my iPad

On 25 Apr 2026, at 1:03 PM, 'b alex pettit jr' via Society of Amateur Radio Astronomers <sara...@googlegroups.com> wrote:


Hello Ayushman,

Thanks. Not sure Rinearn is any improvement over your software, but its nice we can Both Plot using the same format !

Regarding the Gradient_Color_List, the colors are in Quads RGBI :  Red_Green_Blue_Intensity ;  ......
You can change the list to just a few or extend the list of color quads and the software will blend the transitions.

standard
<1777135940493blob.jpg>

<1777136201053blob.jpg>

<1777136250717blob.jpg>


<1777136319132blob.jpg>


=================================================================================

A suggestion : Verify the "dB" scaling of your data .

Use a 50 ohm terminated LNA as the noise source and impose several steps of attenuation into the SDR,
process by your Software and verify there is consistency .. 

Adding a fixed Attenuator on the input to the SDR seems to improve the test results - 
probably because it creates a constant 50 ohm resistive Z on the SDR input vs what would normally be done :
 comparing attenuated signals against a directly connected LNA<>SDR for '0'dB reference.

<1777135438053blob.jpg>

Your values seem a bit high ..  
I've found 3dB over cold sky  is a typical max value regardless of dish size ... even to 12 meters in diameter !

Alex
==========================================================

On Saturday, April 25, 2026 at 10:10:51 AM EDT, Ayushman Tripathi <ayushmantr...@gmail.com> wrote:


Hi Alex,

Here are some plots using the formats you shared: HC_blue, True-Zaxis, etc.

Your scan at Dec +60 DEG looks very nice. My dish is currently pointed at Dec +40, next time I visit, I'll try Dec +60. I had to put the dish away from the city, it's near a forest with very little RFI, and it sends data back over cellular internet. I put the Raspberry Pi, cellular modem, UPS, etc. in a metal box, the only thing outside the box is the antenna for the cellular router. No Wi-Fi is used, everything runs over an Ethernet cable.

Thanks.

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<1777135438053blob.jpg>
<1777135940493blob.jpg>
<1777136201053blob.jpg>
<1777136250717blob.jpg>
<1777136319132blob.jpg>

b alex pettit jr

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Apr 25, 2026, 5:34:33 PMApr 25
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Hi Ayushman,

Process data from several days individually and plot this region. 
Does each show this same Light/Dark pattern ?

Inline image

Inline image

Alex
=========================================

b alex pettit jr

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Apr 26, 2026, 9:08:13 AMApr 26
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VERTICAL_SPLIT   (Hidden Option)

If this text is added to the upper left ( currently empty ) cell of the CVS file, 
 the LINES function will draw each spectrum  as an individual line on the plot.

Inline image
Inline image


Regards,
Alex
===========================


Ayushman Tripathi

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Apr 26, 2026, 2:18:39 PMApr 26
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Hi Alex,

Thanks.

Yes, I found an issue with one of the 15 days of data I was using for the stacked plot, it had incomplete data. After removing that day and regenerating the stack, the pattern is no longer that noticeable.

Attached is the new 14-day stacked plot, along with a few individual day plots that go into it. I'll experiment more with this later today.

I'll also try VERTICAL_SPLIT, right now the CSV I'm loading into Rinearn is already multi-day stacked by my own pipeline before I send it in.

Thanks.

Screenshot From 2026-04-26 13-47-47.png
Screenshot From 2026-04-26 13-47-36.png
14days-stacked.png
14days-stack8th.png
14days-stack10th.png
14days-stack14th.png
14days-stack15th.png
14days-stack16th.png
14days-stack17th.png
14days-stack18th.png

Ayushman Tripathi

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Apr 26, 2026, 8:46:07 PMApr 26
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Hi Alex, I tried VERTICAL_SPLIT, and it's really cool. I'll experiment more with it. Thanks

Screenshot From 2026-04-26 20-40-46.png

Ayushman Tripathi

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Apr 27, 2026, 6:41:38 PMApr 27
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Attached is the last 7-day stacked data with VERTICAL_SPLIT, and a VLSR-corrected 3D plot.

2704graph3d03.png

2704graph3d.png
2704graph3d02.png

2704graph3d04.png

Ayushman Tripathi

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May 12, 2026, 7:04:46 PMMay 12
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Hi,

Here's a plot I made with Starplot using the same data.

Also for my smaller 1m WiFi grid dish, I'm getting a telescope alt-az mount with tripod and adapting it for the dish, and I'm building a new cantenna for the 2.4m dish with a choke ring as per Alex's advice. I'll share photos soon.

I also ordered a NanoVNA V2 clone from eBay, the smaller one, for $64. Not sure about the quality, but the price looked good, so I'll give it a try.

Thanks.
skyplot_starchart_14day.png

NanoVNA:
Screenshot From 2026-05-12 19-01-23.png


b alex pettit jr

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May 12, 2026, 8:39:21 PMMay 12
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Hello Ayushman,
The narrow beam width of the 2.4m dish is quite apparent in the plots.
Clean RFI free data !

The " StarPlot" is interesting.

Regards,
Alex
================

On Tuesday, May 12, 2026 at 07:04:58 PM EDT, Ayushman Tripathi <ayushmantr...@gmail.com> wrote:


Hi,

Here's a plot I made with Starplot using the same data.

Also for my smaller 1m WiFi grid dish, I'm getting a telescope alt-az mount with tripod and adapting it for the dish, and I'm building a new cantenna for the 2.4m dish with a choke ring as per Alex's advice. I'll share photos soon.

I also ordered a NanoVNA V2 clone from eBay, the smaller one, for $64. Not sure about the quality, but the price looked good, so I'll give it a try.

Thanks.
skyplot_starchart_14day.png

NanoVNA:
Screenshot From 2026-05-12 19-01-23.png



On Monday, April 27, 2026 at 6:41:38 PM UTC-4 Ayushman Tripathi wrote:
Attached is the last 7-day stacked data with VERTICAL_SPLIT, and a VLSR-corrected 3D plot.

2704graph3d03.png

2704graph3d.png
2704graph3d02.png


Ayushman Tripathi

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May 19, 2026, 11:17:22 AMMay 19
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Hi Alex, thanks. I had to stop observations this week with my larger dish for a few days due to a storm, as winds are expected to reach up to 70 km/h. Next time I go there, I’ll install guy wires to better support the dish. I’m still waiting for the telescope mount with a small pole fitting for my smaller grid dish.

Also, I think Nooelec SAWbird+ is out of stock again, https://www.nooelec.com/store/sdr/sdr-addons/sawbird/sawbird-h1.html ,though I can still find it on Amazon.

Ayushman Tripathi

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May 29, 2026, 1:31:32 AMMay 29
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Hi, I finally completed my new cantenna today! Will be testing it with NanoVNA measurements and live observations this weekend, and comparing results with previous build. Also will try to add a choke ring.

IMG_1790.jpg

IMG_1789.jpg
IMG_1785.jpg

b alex pettit jr

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May 29, 2026, 5:16:36 AMMay 29
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Hello Ayushman,

Looks Great .

There are two parameters which determine tuning:
The length of the feed element and its spacing to the back of the waveguide

Inline image
Alex

Ayushman Tripathi

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Jun 1, 2026, 8:45:11 PMJun 1
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Hi Alex, thanks! Here are the results from the NanoVNA tests today:

At 1420 MHz the return loss is around −18 dB, VSWR 1.287, and impedance 48 − j12 ohm.

The deepest dip is actually a bit lower, around 1.26 GHz (−24.96 dB, VSWR 1.12), so the feed is resonating about 160 MHz below the H-line, and 1420 is sitting on the upper slope. I will try adjusting the probe to move that dip up toward 1.42.

But it already looks good enough at the H-line frequency. Will be doing live drift scans this week.

Also, the eBay NanoVNA seems consistent, I verified it against other antennas, and it looks good enough.


Screenshot From 2026-06-01 20-10-28.png
VSWR.pngRL.png
Screenshot From 2026-06-01 20-33-35.png
IMG_1857.JPEG

b alex pettit jr

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Jun 2, 2026, 5:05:09 AMJun 2
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Hi Ayushman,

That should be fine.

Did you include the Blue Coax in the calibration of the VNA ?

Alex
==========================

Miguel Ríos Martín

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Jun 2, 2026, 6:16:10 AMJun 2
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Hello.

Excuse me for jumping into the conversation, but I'm a beginner and I'm learning all this. I've seen that you use a VNA to measure the antenna's resonance and resistance.

I'm struggling with a parabolic dish and its dipole, and I'm also using a VNA for measurements.

My problem lies in the difficulty of adjusting the parabolic arm (its dipole). I can get frequencies close to 1420 MHz with a good S11 value on the arm, but when I connect it to the dish, there's some coupling, and the values change. The minimums shift by a few tens of MHz, and I lose the previous values.

Do you know if there's any trick to properly adjust the parabolic antenna?

With the ezRA program, although it seems to detect the hydrogen line, I can't see that "snake-like" hydrogen signal.

The antenna I bought from Nooelec for this purpose had a 9.3 cm dipole and gave me these minimum values with the VNA:

1720 MHz -> -23 dB
1630 MHz -> -22.4 dB
1530 MHz -> -14.7 dB

That's why I decided to open it up and modify the size of the dipole. I've improved the detection quite a bit, but I can't get the precise values. Perhaps I'm asking for too much?

With the current configuration of a 10.3 cm dipole, I obtained the minimum at 1400 MHz and -16 dB for the complete antenna.

Any advice would be appreciated.

Regards

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b alex pettit jr

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Jun 2, 2026, 6:46:24 AMJun 2
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Hello  Rios,

WELCOME Emoji  !

Which version of the nooelec Dish/Dipole did you purchase ?
The H1 version ? if so, the dipole support tube length is incorrect.

Let me know & I'll create a new thread on this topic.

ezRA is not useful for evaluating or adjusting a system.
=========================================================
    ( comments from Ted Cline )

     ezRA is not calibrated.
     Measurements are not in identifiable units.
    .. ezRA assumes those measurements units are generally consistent.
     Some measurements have higher values than others
. ....
=========================================================

I recommend SDR#  w/  IFavg plugin   
This will create spectral plots calibrated in units of dB relative to Cold_Sky. 
This calibration has been verified and thus can be used to measure the performance of a system

Alex Pettit
====================================
====================================

Miguel Ríos Martín

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Jun 2, 2026, 7:01:44 AMJun 2
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Hello.

I bought this: "https://www.amazon.com/Satellite-Applications-Parabolic-Frequency-Bandwidth/dp/B0C4CGKYBV"

I took the measurements with an AURSINC NanoVNA SAA-2N V2.2.

The antenna arm is 46.5 cm long. From what I understand, the focus of the parabolic dish shouldn't depend on the frequency, right?

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Alex P

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Jun 2, 2026, 12:34:39 PMJun 2
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See this new post, and please use it for further correspondence 

Thanks,
Alex Pettit
====================

Ayushman Tripathi

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Jun 2, 2026, 9:41:43 PMJun 2
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Hi Alex,

Thanks. Yes, the plots above were obtained after I ran the calibration at the end of the coax, right where it connects to the feed, so the cable is fully included in the calibration. I even included the SMA F-to-F connector in the cal.

Ayushman

Ayushman Tripathi

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Jun 2, 2026, 11:30:28 PMJun 2
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Hello Miguel,

Try Alex's suggestions. A couple of extra things for the future:

For the feed, you can look into the Discovery Dish feed - it seems better designed for a beginner system, that's the first feed I got for my smaller 1m WiFi Grid Dish.

For software, like Alex said, you can start with SDR# + the IF Average plugin.

Later, if you want to run 24/7 on a Raspberry Pi or any Linux system, you can try Virgo or use a simple open-source Python script I made for automatic recording and processing using Virgo.

https://virgo.readthedocs.io/en/latest/index.html
https://www.crowdsupply.com/krakenrf/discovery-dish
https://www.mouser.com/new/krakenrf/krakenrf-discovery-dish-accessories/

My smaller dish  (currently waiting for a better tripod mount to arrive)
f1d45a3d-2f32-44ff-bbc7-cd4ac53108f0.jpeg

b alex pettit jr

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Jun 3, 2026, 12:45:57 AMJun 3
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And, there is an alternate path to consider :

SDR# > IFavg > HL3D > Rinearn


This is from the same Dish you own with the Kraken H1 Discovery  Feed processed via the above software sequence.
The software works well and it does not require 'programming' statements .

Inline image

System Performance Eval


Regards,
Alex Pettit




Ayushman Tripathi

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Jun 5, 2026, 4:36:44 AMJun 5
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Hi, I modeled my new 150 mm H-line cantenna in openEMS (https://www.openems.de/) and obtained the VSWR, the radiation pattern (directivity ~8 dBi at 1420 MHz), and a receive-mode view of the sky wavefront entering the aperture.

Simulated VSWR is ≈1.4 at 1420 vs 1.29 measured on my NanoVNA, with the model's VSWR minimum sitting a bit higher in frequency.

A few plots attached:
cantenna2_pattern2D_hline.pngcantenna2_pattern3D_hline_4views.pngcantenna2_Eslice_cavity.pngcantenna2_VSWR.png
cantenna2_rx.gif

Andrew Thornett

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Jun 5, 2026, 4:42:25 AMJun 5
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Hi Ayushman,

I hope you dont mind me using your graphics (with credit given to yourself) in my introductory talks on radio astronomy I give to astronomy groups?

Andy



From: sara...@googlegroups.com <sara...@googlegroups.com> on behalf of Ayushman Tripathi <ayushmantr...@gmail.com>
Sent: Friday, 05 June 2026 09:36:43
To: Society of Amateur Radio Astronomers <sara...@googlegroups.com>
Subject: Re: [SARA] Re: 15-Day Drift Scan at Dec +40 Degrees from my 2.4 m Dish
 
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Ayushman Tripathi

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Jun 5, 2026, 5:10:12 AMJun 5
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Hi Andrew,

Yes, that's fine.

Happy for you to use them in your talks.

I'll also keep improving them over the coming days and check for anything I might have missed in the model.

Glad they’re useful! I'll share the higher resolution versions for these plots.

Thanks

Sent from my iPhone

On 5 Jun 2026, at 12:42, 'Andrew Thornett' via Society of Amateur Radio Astronomers <sara...@googlegroups.com> wrote:


Hi Ayushman,

I hope you dont mind me using your graphics (with credit given to yourself) in my introductory talks on radio astronomy I give to astronomy groups?

Andy



From: sara...@googlegroups.com <sara...@googlegroups.com> on behalf of Ayushman Tripathi <ayushmantr...@gmail.com>
Sent: Friday, 05 June 2026 09:36:43
To: Society of Amateur Radio Astronomers <sara...@googlegroups.com>
Subject: Re: [SARA] Re: 15-Day Drift Scan at Dec +40 Degrees from my 2.4 m Dish
 

Hi, I modeled my new 150 mm H-line cantenna in openEMS (https://www.openems.de/) and obtained the VSWR, the radiation pattern (directivity ~8 dBi at 1420 MHz), and a receive-mode view of the sky wavefront entering the aperture.

Simulated VSWR is ≈1.4 at 1420 vs 1.29 measured on my NanoVNA, with the model's VSWR minimum sitting a bit higher in frequency.

A few plots attached:

<cantenna2_pattern2D_hline.png>
<cantenna2_pattern3D_hline_4views.png>
<cantenna2_Eslice_cavity.png>
<cantenna2_VSWR.png>

<cantenna2_rx.gif>

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b alex pettit jr

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Jun 5, 2026, 5:22:37 AMJun 5
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Hello Ayushman,

You post interesting information !
I Really like the animation .

Thanks,
Alex P


On Friday, June 5, 2026 at 04:36:57 AM EDT, Ayushman Tripathi <ayushmantr...@gmail.com> wrote:


Hi, I modeled my new 150 mm H-line cantenna in openEMS (https://www.openems.de/) and obtained the VSWR, the radiation pattern (directivity ~8 dBi at 1420 MHz), and a receive-mode view of the sky wavefront entering the aperture.

Simulated VSWR is ≈1.4 at 1420 vs 1.29 measured on my NanoVNA, with the model's VSWR minimum sitting a bit higher in frequency.

A few plots attached:

cantenna2_rx.gif



Ayushman Tripathi

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Jun 5, 2026, 4:42:30 PMJun 5
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Hi Alex,
Thanks!

Ayushman Tripathi

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Jun 9, 2026, 8:43:59 PMJun 9
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Hi! I received my new alt-az mount for my smaller dish today and will set it up soon. This looks far better than the speaker tripod I was using, where elevation control was very difficult. Will share results with the smaller dish soon!

IMG_1961.JPEGIMG_1963.JPEGIMG_1962.JPEG

Andrew Thornett

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Jun 10, 2026, 4:07:48 AMJun 10
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Send us photos of the new mount!
Sent: Wednesday, 10 June 2026 01:43:59

To: Society of Amateur Radio Astronomers <sara...@googlegroups.com>
Subject: Re: [SARA] Re: 15-Day Drift Scan at Dec +40 Degrees from my 2.4 m Dish
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b alex pettit jr

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Jun 10, 2026, 5:47:45 AMJun 10
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Hi Ayushman,

for refernce
Pgs 35-45



Inline image
Alex

===============================================================================

On Tuesday, June 9, 2026 at 08:44:07 PM EDT, Ayushman Tripathi <ayushmantr...@gmail.com> wrote:


Hi! I received my new alt-az mount for my smaller dish today and will set it up soon. 
This looks far better than the speaker tripod I was using, where elevation control was very difficult. 
Will share results with the smaller dish soon!


Inline image



Ayushman Tripathi

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Jun 28, 2026, 11:15:25 PM (2 days ago) Jun 28
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Hi!

My 2.4m dish system is working again with my new Cantenna, after it went down from storm damage. It is back on and receiving data, right now it is pointed at DEC +20.

While fixing it I also fixed an RFI source on that system. The SATA SSD (through its USB adapter) was leaking right into the 1420 MHz band (the same issue I had with my smaller dish system). I removed the SSD and switched to an SD card instead, and I saw a big improvement. The only catch is that an SD card in a remote system may die much sooner than an SSD :)

I will share drift scans later this week. For now, here is a plot from a 5 min observation it did today and also a few images of my dish.

Thanks.

IMG_0298.png

IMG_0299.jpeg
IMG_0300.jpeg

b alex pettit jr

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Jun 29, 2026, 5:24:39 AM (2 days ago) Jun 29
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Hello Ayushman, 

You might consider making a few support blocks to take the load off the connector .
Plastic is fine

Inline image
Alex

Ayushman Tripathi

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Jun 29, 2026, 10:42:36 AM (2 days ago) Jun 29
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Hi Alex, Yes, thanks. I'll do that soon to make it more robust. The load is mostly from the LMR400 cable's stiffness. The box only has the SAWbird LNA in it.

Thanks.

b alex pettit jr

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Jun 29, 2026, 10:47:22 AM (2 days ago) Jun 29
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You probably should weather proof the connector also.

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