Need verification of first hydrogen Line observeation at 1420.4058 MHz?

[Anthony]

Screenshots attached of activities 

Thank you!

[mike....@gmail.com]

Anthony,

I hate to be the bearer of bad news but that looks like sdr oscillator spike?  It looks too strong.

The milky way passes over your antenna twice a day and that give a stronger signal. and the signal has some width(100khz +). I live in NW Illinois and the strongest signals from milky way are about 9pm  (esp south toward Sagittarius) and about 1130 AM. Of course there are the other popular hot spots like Cas A, Cygnus, Taurus.  But I like the Milky way because it hits you twice a day no matter what you elevation.

I attached a picture of my sdr display.  I run sdr#  with the IFAverage app .  This addes up the signals over a period of time(this case 4minutes) , displays it and writes a text file with the Freq/strength..  My LNA is the Nooelec sawbird HI+, Antenna is 9ft solid dish with 6" stovepipe feed and nooelec smart sdr.

Good Luck,

Read the forum, a lot of info here.

Mike W9YS

[Anthony]

Oh man, hahaha! Thought I had something! Thank you so much for the validation. Any specific hints on what I should attempt to try?

I appreciate the feedback very much!!!

Thank you!

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[Anthony]

Where do you get the  IFAverage app from? Did a search on Google. 

On Tue, Aug 17, 2021 at 12:13 AM mike....@gmail.com <mike....@gmail.com> wrote:

--

[Leif Johansson]

Sorry this is a bit OT for this thread...

On 2021-08-17 06:13, mike....@gmail.com wrote:
> Anthony,
> I hate to be the bearer of bad news but that looks like sdr oscillator spike?  It looks too strong.
>

I had the same experience and found that different SDRs have very different characteristics in this
respect. Specifically I found that the RASDR4 has a pretty bad spike.

I spent some time with the limesdr GUI looking at ways to minimize noise from the RASDR4 and wonder
if anyone has a good FAQ for configuring the RASDR for radio astronomy.

Cheers Leif

[mike....@gmail.com]

Anthony,

There is an article in the June 2021 SARA Journal.

HI Observation with RTL-SDR & IF Average

by Dan Kowell, AL7RS

Certainly sdr#/ IF Average is not the only program being used.  Read back in the forum and you will find many.

rtl-power-fftw 

virgo

gnu radio

rtl/sdr runner

parac

Also in the last SARA Journal  Aug 2021,  There is a good article on HI observations.

HI Line Observations at Haswell, Colorado: August 6-7, 2021  by Richard A. Russel

It shows some of the many shapes of the HI  which will allow conformation of those sources.

Thank you Rich!   I have just started my all sky survey and was trying to figure out what the different bumps were during the 24 hr scans.

Another  article  I just came across that gives us a check off list of the 60 strongest HI sources for 1420.

Important Celestial Radio Sources   by Whitham D. Reeve

Anthony,  keep reading and trying things.  You'll find the HI.  You antennas look good.

GL

Mike W9YS  

[Anthony]

Hello Mike,

Thank you for the time in responding to my email, the information you provided and the  encouragement!

Many thanks to all SARA members, and I recently just joined SARA! 

Have a winning day!

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[Marcus D. Leech]

On 2021-08-17 8:35 a.m., mike....@gmail.com wrote:

Anthony,

There is an article in the June 2021 SARA Journal.

HI Observation with RTL-SDR & IF Average

by Dan Kowell, AL7RS

Certainly sdr#/ IF Average is not the only program being used.  Read back in the forum and you will find many.

rtl-power-fftw 

virgo

gnu radio

rtl/sdr runner

parac

There's also:

https://github.com/ccera-astro/spectro_radiometer

It doesn't (yet) run with post-3.7 Gnu Radio, but will soon. 

In fact, the CCERA GITHUB repo is full of radio astronomy software that uses Gnu Radio underneath.

Also in the last SARA Journal  Aug 2021,  There is a good article on HI observations.

HI Line Observations at Haswell, Colorado: August 6-7, 2021  by Richard A. Russel

It shows some of the many shapes of the HI  which will allow conformation of those sources.

Thank you Rich!   I have just started my all sky survey and was trying to figure out what the different bumps were during the 24 hr scans.

Another  article  I just came across that gives us a check off list of the 60 strongest HI sources for 1420.

Important Celestial Radio Sources   by Whitham D. Reeve

Anthony,  keep reading and trying things.  You'll find the HI.  You antennas look good.

GL

Mike W9YS  

On Tuesday, August 17, 2021 at 2:03:20 AM UTC-5 le...@mnt.se wrote:

Sorry this is a bit OT for this thread...


On 2021-08-17 06:13, mike....@gmail.com wrote:
> Anthony,
> I hate to be the bearer of bad news but that looks like sdr oscillator spike?  It looks too strong.
>
I had the same experience and found that different SDRs have very different characteristics in this
respect. Specifically I found that the RASDR4 has a pretty bad spike.

I spent some time with the limesdr GUI looking at ways to minimize noise from the RASDR4 and wonder
if anyone has a good FAQ for configuring the RASDR for radio astronomy.

Cheers Leif

--

[Pablo Lewin]

Hi Anthony

Here's a copy of the SDR# with the plugin already installed:

https://www.dropbox.com/sh/ry99xak24iqefeq/AAAVrVssTNLU7cmJ5cpaSHm1a?dl=0

Also if you want to get the latest version of SDR# while installing the plugin, go to this article which explains the whole process step by step

https://www.rtl-sdr.com/cheap-and-easy-hydrogen-line-radio-astronomy-with-a-rtl-sdr-wifi-parabolic-grid-dish-lna-and-sdrsharp/

Finally this is what it should look like once you have the plugin installed:

Also your feedhorn doesn't seem to be well centered (not the cause of your apparent lack of SNR problem) I have a very similar feedhorn and what I did to center it perfectly was to drill a pinhole in the back of the feedhorn and I shine a green laser through it , when the laser is perfectly perpendicular with the back of the feedhorn adjust  to reposition the feedhorn till the laser beam is perfectly centered with the dish....et voila!.

Finally I'd like to see what settings you've selected in the radio settings (RTL-SDR controller menu when pressing the gear looking thingy next to the speaker picture on the SDR# software..upper left).  Is the LNA being powered? also try to check the RTL AGC and Tuner AGC  boxes  and on the SDR# main menu under signal diagnostics check enable to see your power settings in db...

Feel free to contact me offline at 

pabl...@gmail.com for any further questions you may have.

Regards

Pablo Lewin WA6RSV

[Anthony]

Thank you Marcus! 

I was reading an article published by you and Ken Tapping on interferometers. I went through an older article written by Jim Abshier. The goal one day is to hopefully construct a RAS interferometer, but from what I've read and watching multiple SARA forum posts, it's very difficult to achieve. Especially when I'm still figuring out how to configure my RAS telescopes to just observe Hydrogen-L on 1420 MHz frequency.

There is quite a bit of math involved for interferometers, and knowledge around phased-array, phased difference, phase locking, image fringe, plane wave, main & side lobes, aperture synthesis, electronics & software involved among other things.

My current plan is to use one or two Raspberry PI4 (PoE hats installed), and one Mini-PC, with a water proof containment, fans with electrical power or solar panels (batteries for charging) for the two, 3-meter RAS telescopes. So far the test I did with one of the 3-meters ran 4.5 hours before the lithium battery & laptop battery were drained. I used Windows Remote Desktop to access the temporary Windows laptop over WIFI to use Airspy SDR Studios & Stellarium. From all the SARA posts I've been reading, I have concerns about WIFI causing interference and the Raspberry PI 4 using PoE. 

I love the SARA post, some are way over my head but I do lots of research on the subjects, especially what seems to be easy to some members is a bit tough for my comprehension, especially coming from being an amateur optical astronomer. I've a few books, guess which one I'm struggling with, hahaha!

• Radio and Astronomy Projects for Beginners, by Steven Arnold (second edition)
• Fundamentals of Radio Astronomy Observational methods, by Jonathan M. Marr, Ronald L. Snell and Stanley E. Kurtz (way over my head & requires lots of research)

I'm in this for the long haul and really love this new science endeavour and looking forward to learning from all of SARA members.

http://www.ccera.ca/papers/rtlsdr-based-software-defined-radio-alternative-to-switched-radiometers-for-continuum-radio-astronomy/

http://www.keoscientific.com/Documents/DTP_RX.pdf

http://websites.umich.edu/~lowbrows/reflections/2007/jabshier.1.html

Thanks again Marcus and everyone, keep up the fantastic support for those in need of assistance!

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[Anthony]

Awesome, thank you for the feedback!! 

Attached is a snapshot of what the settings look like for the Airspy SDR software. When the rain stops, I'll go out and make the corrections to the Feedhorn, it was difficult getting that thing close enough. The focal length for the 3-meter dish is 48", I'm within one inch. 

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[Pablo Lewin]

I'm not clear what SDR you're using BUT if you're using the RTL-SDR then you have to check the offset tuning and set the RF gain slider all the way to the right (maximum gain) THIS is the trick this dongle uses to POWER the LNA. This trick ACTIVATES the Bias Tee (fancy name for powering of the LNA by using the dongle).

Do that first and then we'll take it further

Regards 

Pablo WA6RSV

[Anthony]

Thanks Pablo, 

I'll contact you directly this week, once the weather here in Atlanta clears. Lots of rain and few tornado warnings. I'm quite anxious to get the feedhorn centered and try again.

I'm using Airspy SDR Studio and the Nooelec NESDR Smart v4 software defined radio (RTL-SDR) and Nooelec SAWbird+ H1 LNA, specific for Hydrogen Line (21cm). I just purchased the NESDR SMArTee XTR SDR - Premium RTL-SDR w/Extended Tuning Range, Aluminum Enclosure, Bias Tee, 0.5PPM TCXO, SMA Input. RTL2832U. You'll also notice a Eagle Aspen SHN Power Inverter 18,7VDC, 150mA (upside down) in the attachments. 

Your thoughts Pablo, on the SDR equipment? I'm reading a lot of SDR blogs & SARA posts. 

Thank you!

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[Anthony]

Oops, forgot to add the screenshot attachment of the SDR equipment... 

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[Marcus D. Leech]

On 2021-08-17 4:29 p.m., Anthony wrote:

Thanks Pablo, 

I'll contact you directly this week, once the weather here in Atlanta clears. Lots of rain and few tornado warnings. I'm quite anxious to get the feedhorn centered and try again.

I'm using Airspy SDR Studio and the Nooelec NESDR Smart v4 software defined radio (RTL-SDR) and Nooelec SAWbird+ H1 LNA, specific for Hydrogen Line (21cm). I just purchased the NESDR SMArTee XTR SDR - Premium RTL-SDR w/Extended Tuning Range, Aluminum Enclosure, Bias Tee, 0.5PPM TCXO, SMA Input. RTL2832U. You'll also notice a Eagle Aspen SHN Power Inverter 18,7VDC, 150mA (upside down) in the attachments. 

Your thoughts Pablo, on the SDR equipment? I'm reading a lot of SDR blogs & SARA posts. 

Thank you!

When you power the NooElec LNA through its output coax, it MUST be between 4 and 5V -- if you give it 18V, it will destroy itself more or less
  instantly.

Further, a 3.2Msps sample rate doesn't actually work with these dongles--they drop samples internally.  Try 2.56Msps.

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[Anthony]

Thanks Marcus!! Fortunately I have several more of those LNAs! Figured I'd muck something up, Lol. 

I'll have to purchase another inverter with a rating of 4-5 volts, ASAP! Do you have any power sources you can recommend?

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[Marcus D Leech]

Those power inserters are rated *up to* 20V or so. They’ll happily pass along 5v. 

Sent from my iPhone

On Aug 17, 2021, at 5:31 PM, Anthony <itpart...@gmail.com> wrote:



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[Anthony]

So I'm good, then.

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[Marcus D. Leech]

On 2021-08-17 5:39 p.m., Anthony wrote:

So I'm good, then.

Indeed.  A power inserter is nothing more than an arrangement of a choke inductor and a capacitor such that DC will flow towards the LNA but not the radio and RF will flow to the radio but not the power supply.  As such, they're fairly "agnostic" about exactly what voltage levels they'll inject.  They're limited by the
current-carrying capacity of the inductor, mostly.

Also, those right-angle type-F connectors are notoriously unreliable.  I used them for a little while and found that the slightest bending tendency caused
  them to break internally.

You should diagnose your setup with no LNA connected, and make sure that when you put 5V on the input to the power-inserter, you get roughly 5V on the
  other end of the cable.

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[Marcus D. Leech]

On 2021-08-17 2:53 p.m., Anthony wrote:

Thank you Marcus! 

I was reading an article published by you and Ken Tapping on interferometers. I went through an older article written by Jim Abshier. The goal one day is to hopefully construct a RAS interferometer, but from what I've read and watching multiple SARA forum posts, it's very difficult to achieve. Especially when I'm still figuring out how to configure my RAS telescopes to just observe Hydrogen-L on 1420 MHz frequency.

There is quite a bit of math involved for interferometers, and knowledge around phased-array, phased difference, phase locking, image fringe, plane wave, main & side lobes, aperture synthesis, electronics & software involved among other things.

A simple two-antennae interferometer is pretty straightforward.  What is more involved and brain-twisting is turning the resulting fringes into
  meaningful *images*.  But with a fixed-baseline two-input interferometer, you can't really produce meaningful images anyway.  But an interferometer
  is MUCH more forgiving than a simple single-antenna radiometer in many ways.  It will get much close to achieving theoretical sensitivity, for example,
  because it tends reject a lot of things that single-antenna radiometers cannot.

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[Anthony]

Excellent advice! 

Pitch the right angle connector, get out the voltmeter for testing 5V input to power-inserter (minus LNA) => test for 5V output on other end of the coax cable, got it!

Doing that now and I'll test the setup without the LNA connected.

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[Anthony]

On the fixed-baseline, two input-interferometer is that where the thinned array curse comes into play?
https://en.wikipedia.org/wiki/Thinned-array_curse

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[Marcus D. Leech]

On 2021-08-17 6:37 p.m., Anthony wrote:

On the fixed-baseline, two input-interferometer is that where the thinned array curse comes into play?
https://en.wikipedia.org/wiki/Thinned-array_curse

I guess that to the extent that interferometers and other types of phased arrays are mathematically related.

In order to form images with an interferometer, you need to take measurements over multiple spacings of antennae.   If you are patient, of course,
  you can "get by" with a single antenna pair, and large number of measurements involving moving the antennas around to carefully-measured
  points on the ground.  This only "works" because the sources that you will make images of that way are said to be "stationary"--they don't change
  noticeably over the time-scales that you'd likely be doing measurements (weeks or months perhaps).

Larger interferometer arrays take advantage of the multiple antennae to provide a number of different spacings all at the same time. An
  N-antenna array (assuming no redundant spacing) can provide

  (N*(N-2)) spacings (or baselines in some descriptions).

An amateur interferometer will (typically, but not always) provide a single fixed spacing, from which you get fringes.  Those fringes give you
  information about positions and brightness of objects passing through the fringe pattern of the interferometer.  But you can't really turn that information
  into useful "pictures of the sky" because it's too sparse to produce such images.

NRAO has some useful documents:

https://public.nrao.edu/interferometry-explained/

https://www.cv.nrao.edu/~sransom/web/Ch3.html

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[Anthony]

Thank you sir!!

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[Anthony]

This information is all GOLDEN!

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[Hamish Barker]

The noelec smartee has a built in, always on bias t power injector to provide 5v to the LNA. Is there a particular reason to add another bias t injector I. Your setup?

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[Anthony]

Hi Harnish,

Oops! I guess not. So, I can connect up the LNA without the inserted? 

I was aware of the Tee-Bias, but guess my understanding wasn't thorough enough. 

Thank you!

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[Anthony]

If that is the case,  how can I verify the LNA is working correctly?

On Tue, Aug 17, 2021, 8:32 PM Hamish Barker <hamish...@gmail.com> wrote:

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[Marcus D. Leech]

On 2021-08-17 8:36 p.m., Anthony wrote:

Hi Harnish,

Oops! I guess not. So, I can connect up the LNA without the inserted? 

I was aware of the Tee-Bias, but guess my understanding wasn't thorough enough. 

Thank you!

This might be helpful in understanding a bias-T.  When you look at the schematic, it's clear as to why it's called a T :)

https://www.everythingrf.com/community/what-is-a-bias-tee

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[Paul Oxley]

Marcus & Anthony

If the bias T is in the LNA, then the DC would be on the coax cable. That means that you would likely need an additional one on

the other end to insert the DC. Most of the LNBs used for TV via Satellite have the bias T built in. The other end is supplied by the control box for the LNBs. It contains the matching bias T.

Paul

https://groups.google.com/d/msgid/sara-list/4b255728-d0ce-d707-6e73-1eca01128be3%40gmail.com

.

[Marcus D. Leech]

On 2021-08-17 8:40 p.m., Anthony wrote:

If that is the case,  how can I verify the LNA is working correctly?

One test, which works only if you can independently control the power going to the LNA is to turn the LNA on/off.  The noise floor in your spectral display should go up by 10-20dB when you turn the LNA ON.  That might be a justification for maintaining an external bias T, since you can turn the DC power on/off without
having to disconnect anything in the RF chain.

At CCERA (http://www.ccera), we have a multi-channel (currently 8) LNA bias power-control panel that uses external bias-T very similar to the one you have.
  Each channel has its own lighted toggle switch so we can control it per-channel, and perform the kinds of  rough diagnoses I'd suggested above.

Amateur Radio Astronomy is rather unlike amateur optical astronomy in many ways.  One of which is that you really require some experience in
  electronics to be immediately successful.  There are no real "plug and play" systems out there, and even if there were, there'd still be a fair amount of
  "learning how the plumbing works".   The Internet Age helps tremendously, of course, because there are forums like this one where you can ask
  questions, and get hopefully-helpful answers.  But I would encourage you to read the first few chapters of the ARRL Radio Amateurs handbook--not
  for any particular radio-astronomy knowledge, but for basic electronics, and RF things that all disciplines that use radio have in common.

It's easy to get bogged-down in some of the more complex academic treatments of radio astronomy, and lose site of doing simple experiments that,
  while they won't win you any Nobel Prizes, will definitely provide years and years of self-education and results that are meaningful to you.  You'lll
  end up learning a lot of engineering on the way as well...

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[Anthony]

Ugh!! The RTL-SDR can power the LNA, with its built in Bias-Tee. Sigh, I need to step back and review and understand my complete setup. I'm making too many mistakes.

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[Marcus D. Leech]

On 2021-08-17 8:47 p.m., Paul Oxley wrote:

Marcus & Anthony

If the bias T is in the LNA, then the DC would be on the coax cable. That means that you would likely need an additional one on

the other end to insert the DC. Most of the LNBs used for TV via Satellite have the bias T built in. The other end is supplied by the control box for the LNBs. It contains the matching bias T.

Paul

Indeed, the NooElec SAWBIRD H1 LNA is willing to take power from the output connector--just like an LNB.   External
  CATV/SATTV bias-T are routinely available and Anthony has one.  But it was pointed out that one of his two
  RTL-SDR *receivers* includes a built-in bias-T to inject +5V into the coax-cable that feeds it, eliminating his
  need for an external bias-T to supply +5V up the cable.

My own preference (having dealt with this operationally at CCERA for a few years now) is to have a control panel to
  provide DC power individually for each RF cable that goes to an antenna.  We have 8 channels divided among two
  19" rack panels, and there are "Aska PI-10" power-inserters (bias-T) on each channel behind the panels.

As shown here:

https://photos.app.goo.gl/BvSqcc22s1mTtoLcA

There's a 15V Hammond 1980s-era linear power supply that provides power for this arrangement.  It's very quiet--being
  linearly regulated and built by Fred Hammond himself before he passed away.

I use 15V because any "droop" along the coax will be small, and then I regulate down at the antenna end to whatever
  voltage the LNAs require--these days they're nearly all 5V, or sometimes 3.3V.   A couple of our channels will have
  fairly-ordinary LNBFs on them, which can usefully use anywhere between 12 and 20V--again they regulate internally
  to whatever they actually need.

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[Anthony]

Awesome write up! 

I agree, I had to put down those hard to understand books, though I did research and learn quite a bit from them, but still missed the basics of configurations. You're right this is not the world of Windows OS, and plug-n play but understanding the plumbing and Radio electronics. 

I will review, Radio Amateurs handbook--no. I had to take 30 minutes and collect my thoughts on understanding the electronic components and getting all of these electronics to work together with the software.  

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[Pablo Lewin]

Anthony the Nooelec SDR that you are using has a built -in ALWAYS ON Bias Tee. Unlike the standard RTL-SDR which is software controlled by checking the offset and sliding the RF gain to max..so as long as the LED on the LNA is ON, that means that the LNA is being powered and it's operational.

I have that SDR from Nooelec but through my experiments I determined that the RTL-SDR is way better for this purpose...don't ask me to quantify it or to explain it but the RTL-SDR seems mor sensitive and has a better response. HOWEVER the best system is what you have on hand. So it is what it is.

The driven element on your feedhorn should be about 4.8 cm for best SWR (5.3cm is quarter wave).

So your system should be fully operational as is..you need the plugin that's it.

Pablo WA6RSV

[Anthony]

It shouldn't issues if I still use the inserter, as you stated Marcus to provide external power to the coax, feeding 5V to the LNA.

That should should assure the LNA is receiving ample power.

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[Anthony]

I've installed the updated IF app using the link you provide and the IF plugin is currently working with the Airspy software. I can open up the hamburger menu in Airspy and select IF, see a similar menu like the screenshot you provided earlier, but without the configurations. 

I'm using the blog for setting up Cheap RTL-SDR for Hydrogen..., which is really good for walking through the steps to configure Sharp-SDR

I have a laser colllimation tool, buts it's far to faint during the day to align the feedhorn accurately. I can tell you, trying to center the feedhorn on a 3-meter dish is hard, at least for me!

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[Anthony]

Ok, so from your experiments the vanilla RTL-SDR work better than the nooelc bias-tee powered? If so, I'll try that.  

I have four of those RTL-SDRs laying around, purchased them from Amazon, they are of the non-imitation TR types, (I forget the chip set no.) , not in front of my laptop. 

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[Anthony]

Thank you everyone!!! I think, I think I have enough information to start working on getting this setup configured properly!

Awesome information from everyone!!

I'm glad I joined SARA!!! I appreciate the members support and valuable advice & time!!

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[jjm_...@wanadoo.fr]

Hi Anthony

May bey you can have a look at this paper.

It is French written (sorry) but could be easily translated with online tools.

I hope it includes useful information.

Regards.

JJ F1EHN – Radio astronomy page

 

 

De : sara...@googlegroups.com <sara...@googlegroups.com> De la part de Anthony
Envoyé : mercredi 18 août 2021 03:38
À : sara...@googlegroups.com
Objet : Re: [SARA] Re: Need verification of first hydrogen Line observeation at 1420.4058 MHz?

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[B & MR Randall]

Look over paper even if you don't speak French.  ( I don't)  Diagrams & math are mostly the same as English.  A few French words are close to English words & helps understanding.  This is  a good paper & worth your study.

Bruce R.

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[Anthony]

Thank you!!

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[Anthony]

I appreciate that feed back on the paper, I'll dig into it! I need all the help I can get, to come up to speed! Last night I played with the different RTL-SDRs and LNA settings in Airspy & IF Averaging (calibrated background first). I feel much more confident, especially after all the tremendous member support!!

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[jjm_...@wanadoo.fr]

Hi Bruce,

Thank you for your comment.

Regards.

JJ F1EHN

 

De : sara...@googlegroups.com <sara...@googlegroups.com> De la part de B & MR Randall
Envoyé : mercredi 18 août 2021 09:46
À : sara...@googlegroups.com
Objet : RE: [SARA] Re: Need verification of first hydrogen Line observeation at 1420.4058 MHz?

To view this discussion on the web visit https://groups.google.com/d/msgid/sara-list/000c01d79405%241fd921f0%245f8b65d0%24%40net.

[Pablo Lewin]

[Anthony]

Definitely will, after work.

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[Anthony]

How long does the signal spike or is H-Line  strongest, until it passes overhead and weakens?

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[Marcus D. Leech]

On 2021-08-18 10:35 p.m., Anthony wrote:

How long does the signal spike or is H-Line  strongest, until it passes overhead and weakens?

It depends on what part of the Galaxy you're looking at, the beam-width of your dish, etc, etc.

The sky is "full" of neutral hydrogen, but certain the strongest responses will be from passage of the Galactic Plane through
  the beam pattern of your dish.   An hour or two...

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[Anthony]

I was anxious to try another observation, so I started around 10:00pm ET time zone. I used maximum RF gain of 42 dB, in SDR# then set my Sample rate at 2.56 MSPS and checked the Offset Tuning. Frequency correction (ppm) was 4. Screenshots attached. 

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[Anthony]

On screenshot Captured_change4, SDR# froze up and crashed!

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[Pablo Lewin]

Anthony

 

Wait a minute.. do these two things first:

 

1)The mode should be RAW and NOT USB (I think this is the main problem)

2)set the receiver frequency to 1.420.405.000

 

And report back

 

Pablo

[Anthony]

Thanks Pablo!!

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[Dr. Rich Russel]

All,

I have compiled an observation guide for HI and pulsars based on the Deep Space Exploration Guide (DSES) 60 ft dish observations.

I plan on updating with better observations and calibrated data as we get it.

I will also include other radio telescopes and magnetometer data in the future.

Comments are welcome - this is a work in progress.

Thanks!

Rich Russel

[Anthony]

Thanks for sharing!

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[Marcus D. Leech]

Note that the hydrogen profiles for many of these "sources" is ACTUALLY showing inter-stellar hydrogen ON THE LINE OF SITE between us and the object in question.

While Cygnus A, for example, is a very bright continuum source, any H1 profile from that object will be significantly red-shifted far outside the usual range between
  1400-1427MHz.  You're observing the H1 column in that direction, but not from Cygnus A itself.

[Dr. Rich Russel]

Thanks Marcus!

I'll put that as a caveat on all of the HI observations.

Rich

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