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Author Topic: SDR evolution  (Read 43789 times)
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AB2EZ
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« on: January 02, 2011, 10:22:34 AM »

I'm starting this new thread to focus on one aspect of a much longer thread.

I've often heard people comment that an important advantage of a software defined radio... such as the Flex 5000/3000/1500 series and the Flex SDR-1000 (which I have, and use primarily for reception on AM)... is:

"... although the hardware stays the same, the software is constantly being improved to add additional features and functionality".

But, those of us who have designed/worked with software defined systems know that adding features to deployed software defined systems is much easier said than done... particularly if the platforms (hardware and operating system software, drivers for interfaces, data-defined feautres that are activated) are not identical.

Looking back at the versions of the Flex software I've used with my SDR-1000... including the latest beta release 2.16... I'm wondering what new, useful features I have in release 2.16 (other than bug fixes and colorful new user interface choices) that I didn't have in release 1.14.

As was pointed out, near the beginning of the earlier thread, with two antennas, two independent receivers and two associated indpendent displays, I could do some interesting things with noise and interference cancellation (adaptive nulling) that are much more difficult to do with something like a Timewave ANC-4. But I need to upgrade to a Flex 5000 to do those things.

Stu



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K1JJ
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« Reply #1 on: January 02, 2011, 11:23:44 AM »

After spending many hours watching the various SDR videos, reviews and studying the specs, I've come to the same conclusions, Stu.

If it were a simple matter of having a universal transmitter and receiver that stayed the same (no evolution) then new software would be all that's needed over time. But alas, hardware is ever-changing too along with creative ways to interface to it - and adding new hardware bells and whistles never ends.

There is a certain hardware longevity that is governed by how well the manufacturer predicts the future trend of innovation and likes and dislikes of users. The Flex 5000 people appear to have done a good job at this as the stable price and desireability of a 3-year old rig shows.  

I think most hams fear this: They plunk down $3500 for a high-end SDR and within a year a new piece of hardware comes out that is a MUST-have, but cannot be added to their existing rig.  They feel left in the dust and watch the value of their rig drop. That will happen, given enuff time.

Other than that, we can bite the bullet and just live with older technology. There's still guys on with ssb rigs from the 70's who do well. But can they do PSK31, split, RF processing, bandscope, digital readout, etc? Maybe, maybe not.

I think a modular approach, building/selecting  your own discreet hardware, is the best protection against this. The easy way out is to buy a 5000, but then the risk is higher.

T
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KL7OF
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« Reply #2 on: January 02, 2011, 12:16:58 PM »

Yeah...What you said Tom

The ever changing nature of the hardware and the software plus the fact that the operator becomes a beta tester are the reasons I haven't spent any time or money on SDR...I'm still very interested, but don't have the time to devote to SDR right now....
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KC2ZFA
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« Reply #3 on: January 02, 2011, 12:26:15 PM »

after the June 30, 1948, press conference that announced the transistor there was
a technical demonstration for relevant specialists on July 20 of that year. Lee de Forest
was invited but he declined to attend with the following (paraphrase): I cannot attend
the wake of my 42 year old infant, the Audion, and I suspect that the internment
of the remains will prove to be a long, time-consuming process.
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KL7OF
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« Reply #4 on: January 02, 2011, 12:27:50 PM »

In reference to the other thread that Tom started,  I would like to have a software defined spec analyzer ONLY....No TX , No software to keep updating.Just a spec analyzer to monitor the transmitters with...
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Mike/W8BAC
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« Reply #5 on: January 02, 2011, 07:30:03 PM »

I have been an SDR fan from early on. W9AD and W8ER got me hooked and I'm happy with the plain vanilla SDR 1000. I am still running version 1.10.4 software. I don't care to change software just to see a different GUI. I hold out for actual software changes to the radio.

One problem I have run into is a bit of prejudice on the part of the Flex software side of the house towards making newer digital modes work and paying no attention to suggestions regarding fixes to the software for AM.

I wish we had an AM oriented software genius here that could pry the lid off PowerSDR (open source software) and invent a few lines of code that gives us a noise blanker or two that work for AM. Simple truth is the noise blankers have no effect in the AM mode because they didn't think it needed to be addressed and other newer and more interesting modes take the higher ground.

At the end of the day The flex 1000 is a fun receiver to use every day. I have been running it for years and I can still say it's fun. It just needs a few AM tweaks.

Mike
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K1JJ
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« Reply #6 on: January 02, 2011, 07:46:11 PM »

I'll send them an email and tell them I am thinking of buying a Flex 5000, (which I am) but need to know why the noise reduction does not work on AM...   I can be very persuative if need be... Grin

T




Initial msg sent to the Flex sales dept:


"Hi,

I am interested in buying a Flex 5000 with the ATU and the 2nd receiver.

What is the delivery time for these?


Also, someone on an AM forum warned me that the PowerSDR software noise reduction features do NOT work in the AM mode. Can this be possible???  AM is my main activity and I am expecting your wonderful noise reduction system to be fully functional on AM....?

Thank you.

73,

Thomas Cathey, K1JJ

CT"
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« Reply #7 on: January 02, 2011, 07:58:21 PM »

The noise blanker in powersdr works well for me in AM....
Modulation relative to the carrier is easily adjusted too.
I think it started as version 1.0.8 ?  something like that... maybe 1.8.0 ?
I don't remember...

Kicker is... it won't worke with flex-radio now!   Grin

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« Reply #8 on: January 02, 2011, 08:03:05 PM »

I've never been much interested in SDR because it seems like you usually have to have a Windows PC to run one and I don't want to blow hundreds of dollars on a Windows PC only to run a ham rig.  I also don't like depending on a PC to run a rig.  There are enough things to go wrong with the rig, even without a PC.   When the SDR 1000 had been out around a year a good friend got one and spent the following 24 months messing around with it fixing an unending stream of little issues.  When he was done he had spent around $2K on a fancy soundcard, a zillion ferrite cores, an after market TCXO, a newer dedicated PC just to run the rig, then there was the infamous flex radio 11 KHz spur on AM, and then it started blowing the IPA (I think or maybe the PA) repeatedly.   He doesn't have the Flex rig any more and I am extremely glad I never got one.    If I'm gg to fool with a computer I'll do it in my job where I'm getting paid to fool with it, and focus on boat anchors at home (mac user here at home).

Rob
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« Reply #9 on: January 02, 2011, 08:08:40 PM »

Tom,

Thanks for the effort..... However.... Noise "reduction" (as far as PowerSDR is concerned) is for eliminating the carrier squeal when listening to sideband close to an AM broadcast frequency or an AM amateur station. The WORST invention ever made! You probably have them scratching they're heads.  Grin

PowerSDR dose have (I think) two other noise blanker switches for slopbucket that don't work for us. Good luck!!!

Mike
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K1JJ
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« Reply #10 on: January 02, 2011, 08:17:19 PM »

OK, Mike I understand.

I was playing with their demo PowerSDR software and also saw the video demonstration of how the noise blankers work. I'll send a modified email to stop the NL confusion. 

Yeah, Rob, there is always a risk of the computer giving troubles. I've read about it on some of the forums. I worry about QRO and computers too.

But, before I jump in with two feet, I will use the 455kc  down converter as a spec analyzer and receiver first to see how I feel about the whole thing. I may even wait another year or two and use what I have if it looks like better stuff is coming out soon.

T
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« Reply #11 on: January 02, 2011, 08:55:02 PM »



Quote
The noise blanker in powersdr works well for me in AM....


Bruce,

 I gave up trying to get my point heard when Flex was accepting suggestions for new widgets for upcoming releases of software. I followed my submissions for a year at least with no action taken. I gave up because I had nothing to offer except a want. Maybe I'm not holding my mouth right? I have never experienced any noise blanking while using the software. By the way what do you mean when you say

Quote
Kicker is... it won't worke with flex-radio now

I had some problems at first with the Flex. I made a decision early on to make the Flex computer (Windows based) a stand alone system for the TX and audio with limited network access and that part has freed up processor time that might be taken up by other jobs. I had audio problems at first that LOOKED like RF problems but turned out to be some really strange products of overdriving the audio input of the rig. A scope and mod monitor are recommended and learning how to set tilt and overshoot is a must.  I think all of us have heard Dave/W9AD a time or two with his Flex 5000. He sounds awesome to me and he is having fun with the Flex stuff just like I am. Take that fun and amplify it by 3 DB and you might see why I like the receiver so much.

I know Frank/GFZ will chime in with other suggestions for better SDR receivers and he is always right! I guess I prefer an easier path.

Mike
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K1JJ
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« Reply #12 on: January 02, 2011, 09:07:16 PM »

Mike,

I was wondering if I cud put TWO SoftRock Lites (or equiv) in dual diversity using the PowerSDR software or does PowerSDR require two Flex 5000 receivers only? They said something about firmware in the Flex 5000 that communicated with the software on some things.    Maybe a simple plug-in left and right stereo sound card is all that's needed for two boards to activate the many features involving dual diversity, I dunno.

Anyone know?

T
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There's nothing like an old dog.
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« Reply #13 on: January 02, 2011, 09:29:07 PM »

I see the direction your heading Tom. Anyone that has tasted the Dual Diversity fruit is doomed my friend to dissatisfaction with anything less.

I am not qualified to answer your question regarding the use of PSDR in dual diversity mode with anything other than a 5000. I hope you find some reliable positive answers here. I am curious as well.
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« Reply #14 on: January 02, 2011, 10:32:55 PM »

 
Yeah, Rob, there is always a risk of the computer giving troubles. I've read about it on some of the forums. I worry about QRO and computers too.


Tom,

A lot of it has to do with an individual's tolerance for surprises.  Things that torque me off and result in my saying bye bye to something and getting a refund may not bother other people.  If I pay a lot of money for something I expect it to work.  If it doesn't I'll put up with a few minor glitches or imperfections but if I sense that the technology is way beyond my troubleshooting ability or a fix is going to be a big time sink, then I send it back.   This is partly what moved me to get into vintage gear.  I think I have a chance at dealing with a broken vintage rig.  I have a shot at understanding the technology.  Something new with a black square inside it that has 100 pins in a 10 x 10 matrix, not much chance here.  If it's a $50 DVD player no big deal.  If it's a $5000 ham rig then I don't like being in that situation with a mystery black box.  I may have distorted or exagerated the situation but I guess basically I like to have ham gear I can get into and make even worse  Grin   I admire people who understand and can actually fix the new stuff but I doubt if I'll ever get there since surface mount etc. isn't what I'm really interested in. 

rob
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KF1Z
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« Reply #15 on: January 02, 2011, 10:50:55 PM »

By the way what do you mean when you say

Quote
Kicker is... it won't worke with flex-radio now


The power sdr software I have was re-written for the Genesis SDR kits that I have...

The fellow doing the software had left out AM, axcept for recieve..
When I gave him my list of wants, he went right to it....

He told me he didn't waste any time with it before, because he didn't think it was even LEGAL to transmit AM in most countries.! ( He's in Serbia )

I set him straight on that one, and he restored AM functionality...

I am able to block out a lot of noise, lightning static, electric fences... etc...
At least mostly....
But I never use that stuf anyway, because no matter what you do... if you take away noise... you take way part of the signal (fidelity) ...



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K1JJ
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« Reply #16 on: January 03, 2011, 12:43:39 AM »

Bruce,

That's a cool S-meter. Is that a stock option or did you add it in?

I was just reading about the Genesis. I didn't realize it was a QRP transceiver. How are the receiver specs compared to say the 5000 or a Perseus?  Transmitter IMD?

I have an MRI SS linear that might be a good interface for one. The price at $350 is pretty good - plus it's standard lead in hole construction.

I'm wondering if two could be put together and used with the same software in dual diversity RX too...

T
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Use an "AM Courtesy Filter" to limit transmit audio bandwidth  +-4.5 KHz, +-6.0 KHz or +-8.0 KHz when needed.  Easily done in DSP.

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There's nothing like an old dog.
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« Reply #17 on: January 03, 2011, 03:18:09 AM »

I used this S-meter on my Flex 5000.

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« Reply #18 on: January 03, 2011, 10:27:51 AM »

Flex has zero interest in AM. I sent them some suggestions on how to make sync AM detector better by changing the loop constant after lock to get better fidelity, back in 1000 days. I got the idea it could be done in software after seeing Chuck's modified SE3 in action. Alberto's SDR has the best sync detector for am with a phase meter so you can see FM and drift on the signal.
Alberto is behind a lot of the Perseus software, very sharp guy.
I just read a post on HPSDR on the diversity using 2 Mercury receivers. The user was quite happy with and posted some audio. Once the new inferace module hits the street in Feb. the USB bottleknect will go away.
Flex one upped HPSDR in the 5000 going to fire wire. HPSDR will fix this in a few weeks. 
The new interface module will be the second module replacing the first configuration. The Janus was the I/Q audio interface for SDR1000, Softrock or homebrew. It may come back as an Audio generator / spectrum analyzer once test equipment modules happen.
I wouldn't waste my time with anything Flex unless you can get it cheap.
A used Perseus is the best value out there for most modern configuration.
QSR1 is a Mercury without an RF amp, same hardware.
I'm very happy with HPSDR and  the ability to upgrade modules.
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WA3VJB
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« Reply #19 on: January 03, 2011, 11:34:17 AM »

Frank and Mike had the same experience I have had regarding staffers at FlexRadio Systems, and whether they're receptive to the development and use of their products on AM.

I spent a half hour with one of their people at the Dayton Hamvention a few years ago, at the company's display in the exhibit hall.  While standing there, the guy seemed interested in my assessment of how well the Flex 1K was doing among users in the AM Community, and he asked a few questions that indicated he wanted to know more.

So with that response from him, we kept talking.  I suggested that the marketing people at FlexRadio Systems ought to consider a tailored push toward the AM Community, even to the point of re-branding one of their models to include some features of specific interest to our part of the hobby.  He actually took notes.

I followed up with a few phone calls to their home office at Austin, Texas, and never got called back.

With what I now hear from you guys, it sounds like they couldn't be bothered.

It's their loss.  We outnumber some of the groups they do market toward, both in raw numbers and in weekly hours of airtime.  Both would have been a strong marketing advantage now that competitors are off the starting blocks and catching up with products that may do the job better and be more satisfying to use on AM.

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KF1Z
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« Reply #20 on: January 03, 2011, 11:42:15 AM »

Bruce,

That's a cool S-meter. Is that a stock option or did you add it in?

I was just reading about the Genesis. I didn't realize it was a QRP transceiver. How are the receiver specs compared to say the 5000 or a Perseus?  Transmitter IMD?

I have an MRI SS linear that might be a good interface for one. The price at $350 is pretty good - plus it's standard lead in hole construction.

I'm wondering if two could be put together and used with the same software in dual diversity RX too...

T

S-meter is stock...
$350 kit gets you 10mW output.. add $129 for a 10 watt amp.
Some SMD , but not many.
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« Reply #21 on: January 03, 2011, 12:59:27 PM »

I heard a year or two ago from a very reliable source (otherwise I would not be posting this) who had conversations with the Flex guys, and was told that they, or one of them who partly calls the shots, didn't like what was going on with the SDR-1000 and the super wide ESSB users so they started making a conscious effort to limit their product focus to the standard SSB/CW crowd--average bandwidth down to space shuttle audio.  Could be that they lumped AM in with ESSB.  I think their newer rigs, or two of them, have tx frequency response limits whereas the earlier rig was limited only by what your soundcard could do.
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« Reply #22 on: January 03, 2011, 02:22:15 PM »

It's their loss.  We outnumber some of the groups they do market toward, both in raw numbers and in weekly hours of airtime.  Both would have been a strong marketing advantage now that competitors are off the starting blocks and catching up with products that may do the job better and be more satisfying to use on AM.


Considering the number of AM stations I've heard using Flex rigs on AM, and how great they sound (even by your own admission on several posts in the past), I'm sure their "loss" is minimal.
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« Reply #23 on: January 03, 2011, 02:28:38 PM »

I heard a year or two ago from a very reliable source (otherwise I would not be posting this) who had conversations with the Flex guys, and was told that they, or one of them who partly calls the shots, didn't like what was going on with the SDR-1000 and the super wide ESSB users so they started making a conscious effort to limit their product focus to the standard SSB/CW crowd--average bandwidth down to space shuttle audio.  Could be that they lumped AM in with ESSB.  I think their newer rigs, or two of them, have tx frequency response limits whereas the earlier rig was limited only by what your soundcard could do.

My Flex 5000 can go out to 20K bandwidth on transmit and receive. The Flex 3000 can go out (with PowerSDR 2.xx software) to around 7K. Don't remember what the Flex 1500 does and too lazy to pull up the specs/manual.

If I remember correctly, back in the "good of days of SDR-1000" W3DUQ and several others passed along some AM related issues in the early software that was incorporated in later versions.
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« Reply #24 on: January 03, 2011, 02:50:50 PM »

To address the noise blanker "does not work" statements, last night I tried the following test.

Last night I fired up the Flex rig on HF but found very little in the way of any perceived impulse noise. So, I switched the rig to 6 meters, the AM mode,  and set the receiver on a beacon frequency, 50.068 MHz, located up in North Jersey.  With the beam directed at them, it was well received and well over any noise. Then, rotated the beam about 90 degrees and pointed it at some 10KV overhead lines that were about 1/8 mile away. Impulse noise from the lines rose to about S6 and the beacon was lost in the noise. Engaging the noise blanker on the Flex removed the impulse noise down to a very small barely perceptible rush and the beacon was now fully heard even though its signal strength was down to near zero or S1.  It could very well be that the existing hardware of the SDR-1000, even in combination with the current or past software, was just not that effective in making the noise blanker do its job. I had a SDR-1000 for about two years, but don't remember how effective or non effective the noise blanker function was since I very rarely ever used it.

One has to also remember, the purpose of the noise blankers (there are two of them) is to reduce or eliminate impulse noise. It does not eliminate atmospheric static or other types of noise that you might be hearing. And like most noise blankers, depending on how high or where you have the various levels set, engaging it sometimes degrades the quality of the receive signal. Why you would want to use it on AM, or be an issue for AM reception, is a mystery in itself.
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