SDR-101

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  • Updated 3 years ago
  • (Edited)
Here is a link to my most recent presentation that I presented to a full house at the Palomar Amateur Radio Club in San Diego today.  It covers the history of the different architectures used by Ham Radio Operators over the years and the development of SDR's.  It goes into a bit of detail as to how SDR's work and  more important shows the benefits to Ham Radio Operators for using Modern Radios.  I definitely include my personal opinions and prejudices which you are free to agree or disagree with


Please feel to share this link with anyone and everyone...


Modern Radio SDR-101 V1.pdf

 

https://www.dropbox.com/l/qMaun4aqLPfoh5zQyVz4du



I hope you will find it interesting and informative.
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KY6LA - Howard, Elmer

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  • confident

Posted 3 years ago

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Photo of Dan -- KC4GO

Dan -- KC4GO

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Thanks Howard, I'll share this will my local club members. Lot of interest in my 6500.
This will help explain how we got here.

Dan --- KC4GO
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Cliff Batson

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Outstanding, Howard.  Thanks for sharing this excellent presentation.

Cliff (N4CCB)
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Ken - NM9P, Elmer

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Thanks, Howard. Good stuff.
My only nit, would be a suggestion to add to your history lesson Armstrong's regenerative detector as a bridge between the crystal receiver and the superset. The regen ruled for decades as a combination of 1) an increased sensitivity crystal detector when not oscillating, and 2) a self-oscillating direct conversion receiver when it is oscillating.

Thanks for a great slide show.
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Ronald Marcell

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Thanks for the great presentation and for sharing it.
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Watts - K4QJZ

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Thanks Howard, I have a number of Ham Radio friends to share this with who often ask, "Whats the big deal about SDR radios?" Very well put together and informative, I'll second Ken's suggestion on adding the Regenerative detector if you choose to update it in the future. This will help a number of folks, thanks again for the time to put it together.
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KY6LA - Howard, Elmer

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Working on V2.0 updates to include Regen and downgrade ANAN 200 to 2nd Generation

No dates promised for updates. Hi hi.
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Guy G4DWV/4X1LT

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Hi Howard,

Thanks for that. Your presentations are always useful and always find pride of place on my computer.
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Hank Wolfla

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Wonderful review Howard.  I am going to share with all my friends who continue to ask about my SDR adventures.  73 and be well.  Hank, K9LZJ
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k0eoo

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Very well done Howard...  Thanks for sharing and hope FRS can put it to good use as well!  

Dennis, k0eoo
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Reggie-k6xr

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Great review and informative information. I have forwarded to many of my legacy friends!
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Bob G W1GLV

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Fantastic Howard. I will use this for a club presentation. Thanks
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KY6LA - Howard, Elmer

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Email me at Ky6la at Ky6la dot com if you need a copy of the powerpoint
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Ali - 9K2WA

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Thanks Howard for an excellent and a well done piece of work.
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Dave - W6OVP

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Very good, Howard.
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Jim Hawkins / K2JHV

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Excellent job Howard.  I enjoyed the historical overview and the analogy to the comparison between the C130 and 787.
https://www.youtube.com/watch?v=1DWnqk_taac
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Guy G4DWV/4X1LT

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I LOVE the C130 and would have it over a 787 anyday. Full of character, amazing performance and no Li-ion batteries to smoke! Used to fly on them a lot during my military service. My second favourite would be a DC3.
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Jim Hawkins / K2JHV

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(Temporarily off topic) I rode in one once while in the USAF.  It's an impressive turboprop plane and is still used for Hurricane recon.  I'm sure much of the equipment has been updated.  It's one of the best planes ever made.  Toward the end of my service I was trained to repair the doppler system on the DC3 "Gooney Bird" in Vietnam, but got transferred to UDORN, Thailand.
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Guy G4DWV/4X1LT

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OT: (poss last time)

My real, all time fave is the Lancaster Bomber. In my career I have had the honour to treat several members of flight crew and ground staff.
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Rob N4GA

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Howard,

Nice presentation sir!

I actually flipped through every slide. 

How long did it take you to present it?

I do a lot of presentations for my job and they can go a looong time with that many slides!

Regardless, very interesting.

Thanks
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KY6LA - Howard, Elmer

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I timed it to 1 hour. Working on v2 corrections/updates
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Guy G4DWV/4X1LT

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Time to get some YouTube vids uploaded m'thinks.
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N7AIG

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Very nice presentation!

But, I think the first SDR actually happened back c.a. 1989 or so. Marconi Radio + E Systems, working on massive parallel pipelined array processors, controlled by a DEC/VAX computer. I don't recall how we did the I&Q. As far as I can remember, it was done numerically in a big Hilbert transform. We had a 10 MHz pass band, taken from the downlinks of overhead assets.

73 de Dave, N7AIG

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N7AIG

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Based on my own experience, and from the many posts on this blog, it appears that the weak link in the whole system is Windows OS. Given enough time, FRS can work out most of the bugs inside the radios with their DSP + FGPA's. But Windows will continue to evolve in directions that are likely anathema to the needs of SDR.

But Windows, and most other OS, run now on VM capable CPU chips. We ought to develop a dedicated SDR OS that runs alongside the user OS, where you can have better control over the I/O and interrupt processing. No reason, given VM, that this can't coexist with all of Windows, OS X, and Linux.

73 de Dave, N7AIG

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N7AIG

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By way of examples, have a look at the Berkeley Sprite OS, and the X-Kernel (nothing to do with MIT's X-Windows). These were early experiments, c.a., mid-90's to get higher performance from networked, diskless workstations - back in the day when memory was becoming cheap and hard disk space was still expensive. The bottlenecks were in the packet handling of the ISO Ethernet stack, much like many of the current bottlenecks for high-rate audio and I&Q streams.

73 de Dave, N7AIG

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KY6LA - Howard, Elmer

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In VERSION 2.0 of Modern Radios SDR-101 you will find that I have made a number of revisions, corrections and updates to my original presentation on Modern Radio's SDR-101

Here is a link to the PDF Files

https://dl.dropboxusercontent.com/u/10740053/Modern%20Radio%20SDR-101%20V2.pdf

Here is a link to the full Power Point which now takes about 75 minutes to present.  The PowerPoint is Editable... Please Feel Free to use it as long as you give appropriate credit to the author.

https://dl.dropboxusercontent.com/u/10740053/Modern%20Radio%20SDR-101%20V2.pptx

Somewhere in the future I plan to add a section on Direct Up Conversion Transmitters found in SDR radios... but that is another day....
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N4HY, Elmer

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Howard this was SO badly needed.  I am truly impressed.  If I made suggestions would you consider them at your leisure and decide on whether or not to include them?
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KY6LA - Howard, Elmer

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Most definitely. Please send them to mycalll@ mycalll@. Com
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Alex - DH2ID, Elmer

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Howard, I like your presentation.
73, Alex DH2ID
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Joe, KQ1Q

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Howard, your presentation was great. However on page 11 you said "Big Antennas Help". Now *here* is a big antenna, operated by K1JT (Joe Taylor). He's only using a TS-2000, but his antenna has has 61 db forward gain at 70cm. What is the ERP if he's using the legal limit input power? Ironically it's close to what Doc Brown said: "1.21 gigawatts".


Antenna used by above station. Arecibo 1,000 ft. dish, 61db forward gain at 70cm.
(Edited)