SDR evolution

[flintstone mop]

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

I came in  a little late on this thread. I'm not certain what version of Flex software I have for my old Flex 1000 BUT The NB works FB on my radio in AM. I had a nasty street light almost blank out AM QSO's on 160M and cliking it would clean it up almost entirely and the signals were good again.
I always thought the NB was good at pulsed noises, not steady buzz interference.

FRED

[Mike/W8BAC]

I think I started the poor reports regarding the noise blankers and noise reduction as it applies to my SDR-1000 running PowerSDR version 1.10.4 and I maintain they don't work at all for me. It has been a few years since I made my requests for noise blankers that worked for AM and after watching my request on the sidelines for a long time, I just gave it up.

I downloaded the newest software (version 1.18.6) today and while I can use it only in DEMO mode (no receiver) it dose seem that one of the filters seems to work. I also looked up the manual and I have a few corrections to my earlier post.

You have basically four noise blanking and noise reduction buttons with PowerSDR. NR (Noise Reduction), ANF (automatic notch filter), NB (noise blanker) and NB2 (second noise blanker). Noise reduction seems to have some effect in 1.18.6. I won't know how well it works until I try it with a receiver connected. ANF is the carrier squeal eliminator for SSB. NB and NB2 are for impulse noise (I'll have to try them as well). After reading Greg's email I don't expect much until version 2.X is finally released in it's official version since I don't like fussing with the beta versions.

[WB2EMS]

I saw some chat from N4HY on the mail reflectors a while back that seemed to indicate that he was making good progress on fixing the problem with the noise blanking system. From what I recall he seemed to indicate that it would be even better than it was before 2.x broke it. That would be good. I have found it does work pretty well on impulse noise even as it is, and watched a video (one of Burts?) that showed it really knocking down the general background noise and making signals at the noise level pretty usable. I presume that was a version of the software before 2.x broke it.

The automatic notch filter seems to work reasonably well, in SSB modes, but doesn't seem to function in AM mode, which is a shame. There are times when two QSO's are spaced such that it could be handy (of course you can tuck in the filter edge to remove it), as would some sort of manual notch filter that could be clicked into place.
 

[Steve - K4HX]

Muddy bass mostly, since this is where the largest IMD occurs. Also, most receivers exhibit a huge increase in THD at the lower frequencies too. Take a look at the measurements done by Jay, W1VD.

http://www.w1vd.com/BAreceivertest.html

Steve, when listening in the AM mode how does this issue manifest itself? I have definitely noticed some kind of peak distortion in AM mode on heavily modulated signals with every version of PSDR I have used, both with the Flex 5K and my 455kc down converter and wonder if that is what you are referring to.

I see this too, on most AM signals when in AM mode, on the voice peaks. I've wondered about it too, as it seems to be too sensitive to the peaks compared to other receivers on the same signals.

It has never been a serious issue for me since I always use the synchronous detector when operating AM, and SAM seems to receive everything very cleanly.

Agreed. Although it doesn't seem to like Tim's SBE very much.  Had to revert to straight AM when listening to that yesterday.

[Pete, WA2CWA]

I saw some chat from N4HY on the mail reflectors a while back that seemed to indicate that he was making good progress on fixing the problem with the noise blanking system. From what I recall he seemed to indicate that it would be even better than it was before 2.x broke it. That would be good. I have found it does work pretty well on impulse noise even as it is, and watched a video (one of Burts?) that showed it really knocking down the general background noise and making signals at the noise level pretty usable. I presume that was a version of the software before 2.x broke it.

The automatic notch filter seems to work reasonably well, in SSB modes, but doesn't seem to function in AM mode, which is a shame. There are times when two QSO's are spaced such that it could be handy (of course you can tuck in the filter edge to remove it), as would some sort of manual notch filter that could be clicked into place.

The test I ran on the noise blanking the other evening (earlier post) was running PowerSDR 1.18.6 which is the current "blessed" release.

[k6jca]

Muddy bass mostly, since this is where the largest IMD occurs. Also, most receivers exhibit a huge increase in THD at the lower frequencies too. Take a look at the measurements done by Jay, W1VD.

http://www.w1vd.com/BAreceivertest.html

Very interesting measurements.  Unless I'm misreading the data, it appears that using a Softrock SDR receiver and PowerSDR software as a demodulator off of a receiver's IF (e.g. R-390A) gives stellar audio performance compared to the other boatanchors.

Of course, it makes one wonder...why not just use the Softrock as a straight receiver and remove the boatanchor from the chain?

- Jeff, k6jca

[KF1Z]

Of course, it makes one wonder...why not just use the Softrock as a straight receiver and remove the boatanchor from the chain?

- Jeff, k6jca

That's probably because most people don't understand the Softraock is INTENDED to be a stand-alone receiver!

It's " too small to be a good receiver...".
 

[WD8BIL]

That's probably because most people don't understand the Softraock is INTENDED to be a stand-alone receiver!

Of course, it makes one wonder...why not just use the Softrock as a straight receiver and remove the boatanchor from the chain?

- Jeff, k6jca

It's a great little ONE BAND receiver. And without an adjustable oscillator it only covers a portion of one band.

With the Rock Lite 6.2 on an I.F. of an existing receiver you have SDR with bandswitching covering the whole band.
I have a 6.2 on my Drake R4A's first I.F. and it works great. It covers the entire band and I have instant bandswitching. It's the best $12 I've spent in ham radio in a loooooonnnnggg time!

[K5UJ]

Very interesting measurements.  Unless I'm misreading the data, it appears that using a Softrock SDR receiver and PowerSDR software as a demodulator off of a receiver's IF (e.g. R-390A) gives stellar audio performance compared to the other boatanchors.

That's what is done with the Sherwood SE-# sync. detectors.   I think Don does that with his 75A4, and the sync detector drives a tube audio amp.  His 75A4 is pretty much used as an IF strip.  If he sees this he may add some corrections/details.

those THD spec's for the boatanchors are pretty interesting for I assume the rx were all stock, so they reveal some distortion at fairly low modulation levels by modern standards.  I recall some were over 10% THD on sigs. that were 80% modulated.  I interpreted that as the limitation of envelope detectors and wondered why old rx such as the SX28 got high marks for audio.   Maybe it had a product detector?    My 75A3 was unuseable for good audio without a product detector mod and a detector tap out to an extermal p.p. amp.

Rob

[W1AEX]

The test I ran on the noise blanking the other evening (earlier post) was running PowerSDR 1.18.6 which is the current "blessed" release.

Just a comment on the evolution of the NB within PowerSDR Beta versions. I use Beta 2.08 and would have to say that the combination of NB-1 and NB-2 are very effective at removing impulse noise. I am blessed with a location that is generally quiet on HF, but if I point my 6 meter beam to the SW during the day, I can find a noisy pole out there that kicks up to about S-5 on the meter. I placed a 30 second MP3 file at this link if you would like to hear the NB for yourself:

http://members.cox.net/ender/6meter.mp3

The little attached picture is a screenshot of the 6 meter mp3 as it looks in Adobe Audition. The mp3 starts out with the impulse noise present, then you can hear NB-1 drop it down significantly, and then NB-2 removes it completely. I cycled the cascaded noise blankers three times during the clip. The receiver was on 50.4 MHz in the AM mode with a bandwidth of 8 kc. When the NB is adjusted carefully, you can minimize signal degradation on wide signals somewhat, but as Pete said earlier, why would you want to use a NB on AM? it's always best to have the problem fixed at the source.

As far as the Synchronous Detector goes, I would have to say that PowerSDR does an outstanding job with the AM mode. In fact, it sounds at least as good, if not better, than my SP-600 with the tapped detector. I made a recording of (WA1QIX) Steve's exceptional Class-E signal several months ago and placed the 30 second MP3 file at the link below. How's it sound to you?

http://members.cox.net/ender/QIX.SAM.mp3

Rob W1AEX

[flintstone mop]

I saw some chat from N4HY on the mail reflectors a while back that seemed to indicate that he was making good progress on fixing the problem with the noise blanking system. From what I recall he seemed to indicate that it would be even better than it was before 2.x broke it. That would be good. I have found it does work pretty well on impulse noise even as it is, and watched a video (one of Burts?) that showed it really knocking down the general background noise and making signals at the noise level pretty usable. I presume that was a version of the software before 2.x broke it.

The automatic notch filter seems to work reasonably well, in SSB modes, but doesn't seem to function in AM mode, which is a shame. There are times when two QSO's are spaced such that it could be handy (of course you can tuck in the filter edge to remove it), as would some sort of manual notch filter that could be clicked into place.
 

The notch filer is working in my FLEX 1000 AM mode with the old 1.14 whatever software. When those strange carries appear during  a QSO I see them pop up but do not hear them. I wondeyt if some here having issues might be from a computer with not tenbough horsepower or not using  5the supported sound card. I have the DELTA M-Box. The best is theEdirol FA66.....another $500.00 oh well

Fred

[flintstone mop]

Sorry for the last post and all of the errors.
The AMFONE BB still has some gross defect: IF I quote a long reply MY reply jumps up and down as I type and I cannot see my typing errors.,.........I know SM remark will come...........do not make any errors

Any way I use the supported sound card M-Delta and the best being Edirol FA66.
I think the secret for all the whistles and bells and for the hardware and software to be at its peak is the FA66 sound card for the older generation of FLEX. The newer stuff has it's own hardware.
The FA66 needs a fire wire card in the 'puter....another $20.

Are yous guys with issues using supported sound cards in your flex software? And even IQ I.F. cards (softrock)??

Fred

[Pete, WA2CWA]

Sorry for the last post and all of the errors.
The AMFONE BB still has some gross defect: IF I quote a long reply MY reply jumps up and down as I type and I cannot see my typing errors.,.........I know SM remark will come...........do not make any errors
Fred

It's only an issue when using I. E., hence the notation on the left Sidebar: "Best Viewed with FireFox."

[Pete, WA2CWA]

As far as the Synchronous Detector goes, I would have to say that PowerSDR does an outstanding job with the AM mode. In fact, it sounds at least as good, if not better, than my SP-600 with the tapped detector. I made a recording of (WA1QIX) Steve's exceptional Class-E signal several months ago and placed the 30 second MP3 file at the link below. How's it sound to you?

http://members.cox.net/ender/QIX.SAM.mp3

Rob W1AEX

I definitely agree. I can run various PowerSDR versions here including the latest beta release V2.0.16 and the synchronous detector works great. However, the software and computer made large grunting sounds when trying to lock on to Tim's modulated oscillator the other evening. It's even fascinating to watch his signal bounce around on the panadapter screen.

[K1JJ]

Call it an SB-Eliminator (SideBand)   or a SD-Eliminator (Sync Detector)    - take your pick...


I heard a new SBE modulated oscillator on the air the other night.   A W2? had an 833 modulated by a pair of 813's running.

T

[KF1Z]

Sorry for the last post and all of the errors.
The AMFONE BB still has some gross defect: IF I quote a long reply MY reply jumps up and down as I type and I cannot see my typing errors.,.........I know SM remark will come...........do not make any errors

Any way I use the supported sound card M-Delta and the best being Edirol FA66.
I think the secret for all the whistles and bells and for the hardware and software to be at its peak is the FA66 sound card for the older generation of FLEX. The newer stuff has it's own hardware.
The FA66 needs a fire wire card in the 'puter....another $20.

Are yous guys with issues using supported sound cards in your flex software? And even IQ I.F. cards (softrock)??

Fred

"Supported"... means NOTHING.
Many cards work very well, in unsupported mode.

All that is, is a list of cards from YEARS ago, that they tried, worked ok, and wrote a database of the settings that worked well ...

The list is old, there are many cards that are MUCH better than any on the supported list now.

I use the EMU1212.
Blows the doors off the m-audio d44, and the edirol FA66.
Specified SNR of the 1212 is 120db...
The d44 is 99db, the Edirol 105db.
And yes, I had both here to compare...
Edirol FA66 used to be my favorite as well. Does have the handy feature of phantom power for condenser mics though...
As far as SNR and other noise... the FA66 WAS the best.... about 8 or 10 years ago..

Even the lowly E-MU0202 performed better in RX than the Edirol...

The only thing to look out for is 2 channel cards, (such as the emu1212...) that will not allow you to use phone-modes...
The software will not switch between LINE-IN and MIC-IN.
So you must use a second card for microphone input... but this can be almost any cheap input device ( on-board audio... $10 usb devices...etc.)


I've played with dozens of fairly expensive "cards" over the past couple years...
Hands down, the E-MU1212 is the best RX soundcard I've found...
Seconded only be the new Zonar.

Theses cards are current production, and cost less than $200.

[KF1Z]

Also to note...

There are some very interesting "audio devices" coming out, that will be THE thing to use with SDRs that don't already have them built in.

They will breath new life into the old sound-card dependant radios...

I will hopefully have the priveledge of testing one such a device before it hits the market in the near future.

[K1JJ]

http://w9oy-sdr.blogspot.com:80/2009/08/diversity-update.html

Here's an SDR Flex 5K article I received from a vely famous AMer who now owns a Flex 5K with the 2nd RX.  I'm cornvinced this technique will become the receiving edge of the future - noise notching and null steering using two diversity antennas with software.

Listen to the .mpg of the LU station with normal diversity and null steering added.

"With steering off, you get the normal advantage of diversity, but with steering on you get help against fading as well as noise notching. You have to adjust the bulls-eye to give you best readability but once you get used to playing with this it doesn't take long to make signals other wise unreadable quite Q5. "


T

[flintstone mop]

http://w9oy-sdr.blogspot.com:80/2009/08/diversity-update.html

Here's an SDR Flex 5K article I received from a vely famous AMer who now owns a Flex 5K with the 2nd RX.  I'm cornvinced this technique will become the receiving edge of the future - noise notching and null steering using two diversity antennas with software.

Listen to the .mpg of the LU station with normal diversity and null steering added.

"With steering off, you get the normal advantage of diversity, but with steering on you get help against fading as well as noise notching. You have to adjust the bulls-eye to give you best readability but once you get used to playing with this it doesn't take long to make signals other wise unreadable quite Q5. "


T

Hey Tom
Where do you see and hear all of this?? There is an LV call sign I clik on and it's some CW with extreme narrow bandwidth, but nothing giving ability to move the diversity bulls eye around.
Thanks
Fred

[flintstone mop]

Hello
I 'won' a FA66 from ebay for $200 from a guy in Australia.
I'll try to report on any improvement between the M-delta and the FA66.
Flex engineer told me that the better 'cards' show more bandwidth in the panadaptor.

Not many show up used and they still command a high price. NEW FA66 are still near $400. For such 'old technology' they still are in high demand. I'm looking forward to the ability to plug my condenser mic directly into the FA66 and let the computer do all audio processing.

My old M-Delta audio  card and Symmetrix 528 might show up "For Sale"

I'm sure FLex radio folks were trying to optimize their product for plug n play folks. Seems like other sound cards can lead to more headaches. 2 channels 4 channels software switching between mic/line,,,etc

[K1JJ]

Fred,

Here's some actual null steering diversity that was just posted by a guy experimenting with a pair of Mercury SDR boards.   

There are THREE .wmv videos there showing impressive results for noise, BC and 40M.

T


http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/2011-January/013970.html

[Steve - K4HX]

Really nice job on taking out the impulsive noise.

[K1JJ]

Yep, and the guy was using just a couple of simple wires for ants IIRC.


Lucky day.

Posted a message on the HPSDR reflector looking for questions/help and axed if anyone had HPSDR boards for sale. Great help response.  Was offered and bought a complete set of new HPSDR boards to build a transceiver for $550 shipped.  Includes the Mercury/RX, Penny/Exciter,  Atlas/socket frame,  Pandora/cabinet,  Ozy/USB comm interface board,  Janus/ high end soundcard, LHU/power supply for boards - including shipping.  

I still need a second Mercury RX for diversity and a ref clock.  But I gots what I need to get something cooking now.  Heck, just one Mercury board from Germany alone normally costs $437.

One of the guys on the board (K5SO) is making big advances with the diversity null steering. He now has three RX boards working together in null steering diversity.  I told him I'd like to be a beta tester soon. He gladly accetped since no one has tried it on larger gain ants yet, at least anyone who has posted the results. Some big talent there and a very friendly group willing to help. (Just like AMfone - but I'm the brand new newbie there  ...  HA!)

Jump in - the water's fine.

T

[KF1Z]

Hello
I 'won' a FA66 from ebay for $200 from a guy in Australia.
I'll try to report on any improvement between the M-delta and the FA66.
Flex engineer told me that the better 'cards' show more bandwidth in the panadaptor.

Not many show up used and they still command a high price. NEW FA66 are still near $400. For such 'old technology' they still are in high demand. I'm looking forward to the ability to plug my condenser mic directly into the FA66 and let the computer do all audio processing.

My old M-Delta audio  card and Symmetrix 528 might show up "For Sale"

I'm sure FLex radio folks were trying to optimize their product for plug n play folks. Seems like other sound cards can lead to more headaches. 2 channels 4 channels software switching between mic/line,,,etc

Don't sell the delta until after you find out how much noise your firewire interface causes.

Hopefully you'll get lucky.

Like I said before... FA66 IS a pretty good "card"...
Way back when , it was THE card to have for SDR..
If the noise it may generate, and/or the firewire isn't too bad, you'll like it.

( It does say right in the user's manual, that it isn't intended to be used near radios, among other things, becasue it may cause interference!)

I've had three of them over the past 5 years or so... only the one I had recently was unuseable with either of my newer computers.

[Steve - K4HX]

Good score! Did you get the Gemini and Saturn boards?

Yep, and the guy was using just a couple of simple wires for ants IIRC.


Lucky day.

Posted a message on the HPSDR reflector looking for questions/help and axed if anyone had HPSDR boards for sale. Great help response.  Was offered and bought a complete set of new HPSDR boards to build a transceiver for $550 shipped.  Includes the Mercury/RX, Penny/Exciter,  Atlas/socket frame,  Pandora/cabinet,  Ozy/USB comm interface board,  Janus/ high end soundcard, LHU/power supply for boards - including shipping.   

I still need a second Mercury RX for diversity and a ref clock.  But I gots what I need to get something cooking now.  Heck, just one Mercury board from Germany alone normally costs $437.

One of the guys on the board (K5SO) is making big advances with the diversity null steering. He now has three RX boards working together in null steering diversity.  I told him I'd like to be a beta tester soon. He gladly accetped since no one has tried it on larger gain ants yet, at least anyone who has posted the results. Some big talent there and a very friendly group willing to help. (Just like AMfone - but I'm the brand new newbie there  ...  HA!)

Jump in - the water's fine.

T