Softrock / Rocky versus Perseus

[Michiganrailfan]

Correct me if I'm wrong, but is this the forum to ask questions about software options for Softrock Ensemble? I assume it is, so here's the question:

As I look at the more expensive SDR hardware (Perseus etc), they all come with what appears to the newcomer as much more sophisticated software than Softrock......I like the sophistication, as on You Tube I see examples of users "tuning in" to different peaks, applying filters, widening or narrowing the range of frequencies around the central peak, and so on. What a blast. But it seems to do all that I need to blow at least $500.

On the other hand, I read that, with the right antenna and sound card, Softrock with Rocky -- although a low cost system -- performs just fine.

You're probably all aware that Softrock relies on a sound card to get the IQ data into the PC. Do you thin this limits the bandwidth too much (remember I'm a newcomer....I might not need the high degree of sophistication of other systems costing $500 plus?

As an absolute newcomer to this area (I used to play with my Dad's SWR as a kid....a tube model and great fun), I think I'll pull the trigger and get Softrock Ensemble II with Rocky 3.6 and give it a whirl. If I get addicted, I might move toward the more costly "non soundcard limiting" systems.

It's nice having a group of experts lead me through this. I've learned a great deal reading your posts. Thank You.

 

[Token]

As I look at the more expensive SDR hardware (Perseus etc), they all come with what appears to the newcomer as much more sophisticated software than Softrock......I like the sophistication, as on You Tube I see examples of users "tuning in" to different peaks, applying filters, widening or narrowing the range of frequencies around the central peak, and so on. What a blast. But it seems to do all that I need to blow at least $500.

On the other hand, I read that, with the right antenna and sound card, Softrock with Rocky -- although a low cost system -- performs just fine.

OK, lets be very careful with that “performs just fine” line. It performs. It is inexpensive. It probably performs in every way better than anything you can get for the same cost (below $100 USD), in some aspects it is MUCH better than anything in that price range. But it is not in the same performance category as any of the DDC (direct digital conversion) SDRs on the market, such as the QS1R, SDR-14/-IQ, Perseus, Excalibur, etc. No serious, unbiased, third party tester data can be found to support that it is near the same performance. Naturally, the Softrock Yahoo Group will not agree, but then the QS1R group says their SDR is the best, as does the SDR-IQ group, the SDR-14 group, the Perseus group, the WinRadio group, etc, etc.

Facts:
--The SR Ensemble only has 192 kHz of BW with the best 24 bit sound cards, most applications will show less BW with many users never seeing more than 96 kHz. The lowest cost DDC SDR does 190 kHz every day all day, regardless of sound card, the better DDC SDRs do many times this.
--The SR Ensemble has a noise floor of between –110 and –120, depending on the source quoted. This basically means it is 4 to 22 dB less sensitive than the DDC SDRs, if you are unfamiliar with the dB scale that translates to the DDC SDRs being 2.5 to 150 times more sensitive.
--Strong signal rejection of the SR Ensemble is sound card dependant, but 70 dB or less can be expected, 50 dB with a 16 bit sound card. This is 15 to 60 dB worse than the DDC SDSRs (31 to 1,000,000 times worse, yes that last number is indeed one million).
--Dynamic Range of the SR Ensemble is only about 75 to 80 dB, at least 15 dB worse than the lowest end DDC SDR, or more than 30 times worse.
--Because sound cards are not designed for very high precision channel matching, required to give good image rejection, the DDC SDRs typically display 20 dB or more improvement in image rejection over a sound card based unit, that means the DDC SDRs are 100 times, or more, better in this aspect.

However, for software, keep in mind with the SR Ensemble you do not have to run Rocky, you can run some, but not all, of the same software packages used on those other SDRs.

You're probably all aware that Softrock relies on a sound card to get the IQ data into the PC. Do you thin this limits the bandwidth too much (remember I'm a newcomer....I might not need the high degree of sophistication of other systems costing $500 plus?

Sophistication is not the only issue here, performance and features are what the extra money gets you. What might be at issue is you may not hear signals other people hear…and get discouraged.

For bandwidth, even if you only get 96 kHz of BW you will still probably like it, it still works as a point and click map to signals. But as I pointed out above the sound card reliance impacts more than BW, it also affects, among other things, dynamic range, strong signal rejection, and image rejection.

As an absolute newcomer to this area (I used to play with my Dad's SWR as a kid....a tube model and great fun), I think I'll pull the trigger and get Softrock Ensemble II with Rocky 3.6 and give it a whirl. If I get addicted, I might move toward the more costly "non soundcard limiting" systems.

As I said above, you do not have to use Rocky with the SR Ensemble, although it is a fine piece of software. You can also run Winrad, SDR-Radio, and Power SDR, and possibly others as well. All of these give a different feel than Rocky, and more along the lines of the software found with the DDC SDRs. In fact many users with DDC SDRs use one of the ones I listed, instead of what ships with the SDR.

If you go into the SR Ensemble II with your eyes wide open and understand the shortcomings then the price is just about impossible to beat. But it is very important to not go into it thinking “this is just as good without a couple of the bells and whistles”. It is actually, measurably, less good than the DDC SDRs.

That does not, by the way, mean it is “bad”. For the amount of money nothing else seems to come close. And as I said in your other thread, I will be ordering one myself as a play-around rig. There is absolutely nothing wrong with getting the SR, particularly as a “get your feet wet” radio, just don’t mislead yourself.

Have you found a source to buy one assembled? Or are you going to build it yourself?

T!
Mohave Desert, California, USA

 

[Michiganrailfan]

Thanks Token for the tremendous help.

Tony Parks offered me a fully assembled Ensemble. He recommended I buy an enclosure from Tom at

RX Enclosure

I wasn't aware the Ensemble works with the higher end software you mentioned. Great news.

You've been a big help to me as I march up the learning curve. Most important to me is that I now see how to go about comparing apples to apples: study key performance factors of bandwidth, noise floor, signal rejection, dynamic range.

I have a dumb question....

I can understand signal rejection and noise floor, but can you elaborate on the importance of a bigger bandwidth?

Another dumb question: what's dynamic range, why does it matter?

The last dumb question: I'm reading that single side band is important to hear anything else than international stations (e.g.,, marine, military, aircraft). What the heck is this? Does the Ensemble have this feature?

Right now, my wife has control of the checkbook; I'd really like to buy one of the better SDRS, but I recently spend a bundle on a scanner. I know what will happen....I'll buy the cheap SDR and keep the wife off my back temporarily....later I'll get hooked and will buy a better SDR. At that point she will lay an egg. But I guess you guys on this forum know how deal with that variable, when it shifts from background noise to strong signal interference. Is there a special thread on this (kidding)?...it'd be great for the hobby.


Cheers

 

[Token]

I can understand signal rejection and noise floor, but can you elaborate on the importance of a bigger bandwidth?

The wider BW is important to some applications (by application I mean what you use the SDR for, not the software) and means nothing for other applications.

For example, if you want to tune to 9500 kHz at 1230 UTC to listen to the Pashto Service of the Voice of Iran then the displayed and instantaneous bandwidth means little. As long as the bandwidth is as wide as the anticipated audio (and every SDR can do this) then it does not matter. So for broadcast stations the wide BW might be of limited use.

However, a couple of instances that wide displayed and instantaneous BW is important:

For Utility type listening many of the transmissions are on odd, sometimes unknown frequencies. You have to find them instead of relying on them to be up at a certain time on a certain frequency. These transmissions are also often of very short duration with big periods of “dead air” between interesting bits of audio. A wide bandwidth waterfall display means you can “see” with your eyes anytime a signal comes up in the displayed bandwidth. You do not have to be tuned exactly to the freq to detect it, it just has to be within your displayed bandwidth. You can then “click” on the signal, moving the audio demodulator to it and catching the next short duration transmission that occurs.

Without the wide display you would have no idea any signal was being sent except the one you currently have audio on.

Here is an example, this was done with the WinRadio Excalibur. The following edited screen shot consist of four small portions of one wide waterfall display. The entire display is a 32 MB image, so I trimmed out just some exemplar parts. I was actually tuned to and listening on a totally different frequency from any of these. By looking at the waterfall display and looking for synchronized signals I could tell the same transmission happened on all four frequencies. Without the wide bandwidth I could not have told that. Adding all of these to my “watch” list allowed me to catch a latter transmission with the same habits. It turns out there were four simultaneous transmissions of a single EAM (Emergency Action Message), yes, this is common, but it makes a good example . The frequencies used were 6697 kHz, 8776 kHz, 11244 kHz, and 13155 kHz. If I had not known of these frequencies previously I would have just “discovered” the fact that they were all related.
http://www.pbase.com/token/image/130373085/original.jpg

Another useful application for wide displayed bandwidth would be when the signal itself covers a wide band. For example there are many OTHR (Over The Horizon Radar) or HF-R (High Frequency Radar) signals on the bands these days. Some of them are as much as 250 kHz wide. In order to analyze them you must be able to receive the entire signal, not just a portion of it. There are other digital signals that are quite wide, but the 250 kHz radar is fairly extreme.

Another dumb question: what's dynamic range, why does it matter?

Dynamic range is a measure of the ratio of the smallest and the largest signal a radio can receive without distortion at the top end or not hearing at the bottom end. Basically the range of signal strength that it can be reproduce for you to hear, from weakest to strongest.

Broader dynamic range is desirable.

The last dumb question: I'm reading that single side band is important to hear anything else than international stations (e.g.,, marine, military, aircraft). What the heck is this? Does the Ensemble have this feature?

These kinds of transmissions (along with other non-broadcast) are called “Utility”, and yes the majority are in SSB.

Yes, the Ensemble will do SSB, all SDRs are limited in modulation techniques only by their software, unlike conventional radios.

SSB, Single Side Band, is a modulation technique. You are aware, probably, of AM and FM from broadcast radio, those are two other modulation techniques and not frequency ranges as many people take them, Amplitude Modulation and Frequency Modulation. SSB is just another, but many lower end portables do not have it. SSB is most typically either Upper Side Band (USB) or Lower Side Band (LSB). There is also Double Side Band (DSB).

The SDR hardware itself will support all of these modes, the only question is will the software? Good news, pretty much everything I have ever seen supports SSB, and most support many more modes.

Right now, my wife has control of the checkbook; I'd really like to buy one of the better SDRS, but I recently spend a bundle on a scanner. I know what will happen....I'll buy the cheap SDR and keep the wife off my back temporarily....later I'll get hooked and will buy a better SDR. At that point she will lay an egg. But I guess you guys on this forum know how deal with that variable, when it shifts from background noise to strong signal interference. Is there a special thread on this (kidding)?...it'd be great for the hobby.

I am pretty lucky, my wife likes radio also, although she is not active. Her father was into radio and so she has always had radios in the house, for as long as she can remember. In fact, although I built a totally separate radio room in the house (converted a spare bedroom) she made me move my main listening position into the living room, said she did not want me disappearing for hours out of sight. My main ham shack is still in the radio room, she says me yelling in the mic is annoying Essentially when I tell her I am going to get a new toy she just tells me what account to take the money out of. We learned long ago it is best if I keep a “toy” account, separate from any savings or working accounts. And she gets the occasional trip to Tiffany’s or similar to balance it all out.

T!
Mohave Desert, California, USA

 

[Michiganrailfan]

Excellent, excellent help.

I like your discussion of BW fundamentals with the EAM example.

When you mentioned that Softrock can use other software besides Rocky, I looked up SDR-Radio on the web and came upon something entirely new (to me anyway): "SDR over internet". Let me see if I get this straight. It says I don't need my own SDR because many hams have made their SDRs available on the web. Is there a gimmick? It says once I register, I download the software and can essentially jump from one ham's SDR to the next....all while trying out the SDR-Radio interface. This seems too good to be true. How do they make their money?

Lots more learning to do.


BTW, I grew up in Montrose, CA....I have a lot of fond memories visiting the desert with my family.

Cheers

 

[ka3jjz]

While there are paid subscription services out there, many people put their radios - SDR included - out there for the benefit of the hobby, not for a profit. The catch usually involves whether someone allows multiple connections to the radio at the same time. You can't do this with a standard analog radio. Of course you have to have a reasonably fast connection so the audio doesn't 'lag' - otherwise there's no real 'catch'...best regards...Mike

 

[Token]

As Mike said, some people put their SDRs on that, and other services, just because. Just like people put their traditional radios on Globaltuners.com. There is no gimmick on these particular services. Do keep in mind though that they are free, and as such somtimes the radio you want is not online or someone else is using it.

One of my SDR-IQ's is on SDR-Radio.com whenever I am not using it for something else. Mine would be "SWL/Token". However, since we got a new TV, and the new TV is a Plasma, and the TV is only about 15 feet from the radio, it does have some pretty heavy QRM issues whenever the TV is on. And the TV is only on when I am not doing radio stuff…DOH! The noise is not an SDR issue, all of my radios have the same issue with the Plasma, but the SDR makes the noise very visibly evident. 60 diagonal inches of Plasma RFI making madness, but man the picture is good.

I used to have one of my Icom R-8500's on Globaltuners.com, but it had a CPU failure and by the time I fixed it I had dedicated the control PC to other things, so it has never made it back on GT.

T!
Mohave Desert, California, USA

 

[Token]

Buy the way Michiganrailfan, are you familiar with the WUNCLUB channel on IRC? If Utility transmissions (military, aviation, maritime, etc) are what you think your interest will be you might want to check into it, it is sometimes a good source of real-time feedback on what can be heard.

T!

 

[Michiganrailfan]

Thanks again, everyone. Tony delivered a fully-assembled Softrock today. Great fun.

 

[Michiganrailfan]

Quick and dirty antenna for softrock

Yes, I know.....quick and dirty isn't always a good idea.

I'm just anxious to get my Softrock running for the first time.

Here's the problem: it accepts BNC terminated coax. I'm trying to figure out how to connect this to a longwire.....something crude I can get outside and temporarily hang on the railing of my deck.

I'm reading a great deal about different longwire designs.....everyone recommends a balun. I don't have one laying around. And I don't want to wait till Friday when Radio Shack opens up. This may be my downfall.

It turns out I have a lot of coax laying around with PL 259 terminations. Also I have a BNC to PL259 adapter, so it shouldn't be a problem to connect a coax feed line to the softrock.

How to connect a longwire to the PL 259 fitting at the other end of the feed line ?

My quick and dirty idea is to attach the PL 259 fitting on the end of the feedline to a panel mount adapter that has a solder connection on the back side (attached is a photo). The idea is to solder a long piece of wire that I can stretch along the railing of my deck.

Is this insane? Or should I wait till Black Friday and get a balun? I'm like a kid at Xmas.

thanks, I appreciate any help.

 

[Token]

Go ahead and do it. An expedient antenna is better than no antenna. There is no reason not to play around with different antennas until you can do the right thing.

 

[Michiganrailfan]

Trouble with Softrock / Rocky

Hello

Does anyone have experience loading a driver for Softrock Ensemble II on a Windows Vista machine?

I think I'm in over my head. I spent some time on the Yahoo Softrock group, and I'm getting some helpful suggestions, but I think I need a degree in computer engineering to understand the links I'm sent to read. Apparently, there's some problem with Vista. It gets worse when trying to get Rocky to run.....it won't recognize the sound card.

It seems I have 2 choices: buy a USB soundcard or buy a new PC without Vista. Apparently XP is better.

A little frustrated......

 

[ka3jjz]

<bump> to bring the message forward due to the migration... Mike

 

[bagmouse7]

Here is an example of a nice Web based SDR.

WebSDR at OE4XLC

They are fun to play with, but are no substitute for having your own.
It will give you a good idea about how seeing the signals across the bands can be so valuable.
I will also add that once you used one of these nice SDRs with a beautiful waterfall display, you will never want to go back to tuning around the band. It literally becomes point and click to find new signals that you can see on the waterfall.

I think every HF fan needs an SDR in his shack.