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FlexRadio SDR-1000 Review

Robb

Honorary Member Silent Key
Dec 18, 2008
11,432
3,665
323
Silicon Valley CA, Storm Lake IA
Bought this radio almost two years ago and it sat in the box for all of that time. Why? Simply put - it was intimidating. You just don't set these SDR radios up as you would a Kenwood, Icom, or Elecraft. A FlexRadio require an external sound card for one. Then, the wiring between the radio, external sound card, and the computer is not simply accomplished by acquiring and using a CAT cable either. By no means would I call the SDR-1000 a 'plug and play' deal. No chance. No VFO knob or anything familiar on the outside that one would even associate it to be a radio. Except for a BNC plug on the back and a 4 pin mic plug on the front; one would be hard-pressed to identify it as a radio - at all.


The mysterious 'Black Box' radio
The FlexRadio SDR-1000 w/ the Edirol FA-66


sdr1k.jpg


Geheuse~offen.jpg



Not that I don't know my way around a computer - I can build and set them up with the best of them. I just got a bit flakey about getting off of my butt and away from the Kenwood TS-2000. That is a nice radio - too. But now, the time came to unbox this 'Flex' thing and see if I could make it work. I bought it because I heard so many things about it and was curious. The opportunity to buy one came up suddenly, so I took a chance. If you aren't the person that know his way around a computer; then the newer versions of the FlexRadios would be the better choice. The SDR-1000 is a bit fussy to hook up; the very reason that kept me from hooking it up in the first place.

But what really got me going on this project was a local Ham that put together a "Ensemble RXTX" 10-15m kit radio (http://www.wb5rvz.com/sdr/ensemble/) - which is also software dependent (it uses the "HDSDR" software). He was literally raving about how much fun he was having, how well the receiver and transmitter worked, and the fact that the software had the panadapter. It did sound clean and I told him so. He said "Don't you have a FlexRadio; how come you've never hooked it up"? He continued and insisted that I hook up my Flex; so I moaned a bit and said 'OK sure'. Turns out that I'm glad I listened to him and didn't just sell the radio.

The first thing you will notice about the FlexRadio is that it is extremely quiet. Noiseless with the exception of the relays clicking when changing bands. The cooling fan cannot be heard unless you stick your ear right next to it. Even then, you might have to strain to hear it. A Samlex 1223 power supply was used for this review. Neither the radio or the power supply got hot even at the radio's full output. The Flex just doesn't draw much current - apart from the 100w PA.

After a day and a half of struggling to make it work, I got around to reading the SDR-1000 manual. Should have done this in the first place. Hindsight is 20-20 - isn't it? That straightened out what I needed to know. At this point, I knew what questions needed to be answered and the manual delivered. Because the printed manual was so huge, hindsight also tells me that it may have kept me from trying out this radio in the first place.

SDR-1000 Manual link:
http://www.w4ish.net/Manuals/pdf/SDR-1000_Operating_Manual-G.pdf


The Roland Edirol FA-66
fa-66_large.jpg

Although the Edirol is no longer in production, there are few cards today that can match its 24 bit/192,000khz sample rate. This sample rate makes it possible for the panadapter to see 100khz above and below your center frequency. With a lesser sound card; the panadapter sees far less above and below your center frequency. It came with the radio when I bought this radio package from a Ham. One must use a Firewire to keep it up to speed. Has its own mic preamp in it too. I use a Behringer MIC2200 going into the Edirol for a little more gain. These Edirol FA-66's are also excellent for doing your own home recordings if you can find one used. The Edirol sound card is a major player with the SDR-1000. Those who use a lesser card haven't been pleased with the SDR-1000 performance. Those that have it will tell you it is the only way to go with this radio.

This FlexRadio uses a parallel port to USB cable as well. This also requires its own I/O driver. It is advisable to use not a few ferrite clip-ons on this cable; as stray RF will easily interrupt the data flow and sever the connection between the computer and this mysterious black box! I also had to purchase a FireWire PCI-E card in order to get the Edirol FA66 sound card into the computer. Ferrites for the Firewire's cable is also recommended. After installing the Edirol driver, the FlexRadio driver, and the Power SDR software, I was able to start the software for the radio. It finally lit up!

The other problem that I had at first, was figuring out where the three sets of wires went between the Edirol sound card, the Flex, and the computer. Flex has a pdf for that too; so that made the setup easy.

Download link for the SDR-1000/Edirol FA-66 installation:
http://kc.flex-radio.com/KnowledgebaseArticle50180.aspx


Flexradio PowerSDR software screenshot

0.jpg



PowerSDR Software = Flexible

Once it was all set up correctly in the setup menu, It was time to set up the freq cal, level cal, and RX image cal. Used WWV as the reference for that. Takes only a few minutes to set up the software correctly. There is a link below to download the PowerSDR software. You can download it and run it in 'Demonstration Mode'. It wont hurt your computer, comes with its own simulated radio traffic with its wave file, and you can play around with all of the controls yourself. You will easily see that it can be a lot of fun.

Another nice feature of the software, is that it can record a QSO with just a click. The .wav file must then be converted from the 192khz sample rate down to a share-able 48khz by using another software. CoolEdit Pro 2.0 or less can do this. The lesser versions are freeware and easy to use. Or, you can record your voice calling: "CQ CQ DX, this is XXXXX calling CQ DX" so that you can transmit this recording instead of saying it yourself. It's a nice concept and it works, but best used for contesting.

You can quickly change the TX width from 1hz to 10khz in SSB mode. For eSSB, I can run circles around radios that can do 5 or even 6khz wide by going as high as 10kz. Like to see some other radios able to do this. Not that I would; but this radio can. The Compressor, Compander, VOX, and Gate can be used; but these don't work as well as they should - IMO. I don't like the Compressor nor the Compander; but the Gate is excellent and I do use it. Guess I'm spoiled by using the real thing. But if you want to use an outboard compressor with this radio, get a piece of rack gear and one that uses an opto-compressor design for best results - IMO.

These is a few diagnostic programs in the software too.

Latency isn't a real issue - IMO. Some have claimed that. That will depend entirely on the quality of the sound card, the computer speed, and the way you set up the parameters in the PowerSDR Setup/General/Options tab. If the DSP Buffer Size is set to the largest setting; then latency will get worse. If you set the DSP Buffer Size to a smaller setting; the latency vastly decreases. The down side to a large buffer size is that the audio will have a brittle sound; and the opposite is true for a smaller size buffer setting. However, the larger buffer size will make the filter cut off much sharper/steeper; and the smaller size buffer will make the filter cut off more lax and sloppy. For contesting purposes; the DSP Buffer Size should be set on the large size so that adjacent operators will not be affected as much as if they would be if the filter were set to a looser tolerance. One more thing, the buffer size will affect the CPU load. A larger buffer size will demand more from the CPU and the smaller buffer size will have a smaller CPU load. I consider this info important info to have if you own any FlexRadio. It makes quite a difference for latency as well as the other factors mentioned. BTW - I use a quad core AMD 3.2ghz processor with 4gb's of RAM, and a 1gb video card. No hardware 'bottle-necking' (or 'digital hardware restrictions') on the computer that I use for this radio.

To be perfectly honest here, I am merely scratching the surface for what this PowerSDR software can do. I really don't want to shortchange this radio - or you - if you have the curiosity and the time to find out. The scope of what this software can do and how to use it would just make this review much too long. It is my opinion that you would be better served by running the software in demo mode and take some 30 or 40 minutes to learn and explore it for yourself.

PowerSDR direct download link:
http://support.flexradio.com/Downloads.aspx?id=394

This particular radio I bought had some of the options, such as the antenna tuner, TCXO crystal, and the 100w amp. The antenna tuner is the well-known LDG brand. The power amp sports two 2SSC2879 final transistors and supplies a clean ~100 watts - depending the band you transmit on. On 10m; the output is about 85 watts.

You might feel like a pig on roller skates for the first few days. But that will quickly pass as the fun this radio can generate just using it and discovering just how 'Flexible' these radios really are.

The receive is nothing short of 'stunning'. The software makes dealing with DX conditions far easier to do that with a radio with conventional knobs. Just point and click the mouse, and you have filters that can be changed on the panadapter screen and the noise is completely GONE! Try THAT with another radio! Just plain amazing - really. Try out the software link and see for yourself.


Watch it work:

http://www.youtube.com/watch?v=vsDQdAfXJ1Q



SDR-1000 Specifications
Effective Nov 22, 2006 (specifications are subject to change without notice)


Receiver Frequency Range 12KHz-60MHz (Requires external user supplied pre selector for best operation below 160M)
Transmitter Frequency Range 160M-6M Bands (2M transverter IF optional)
IP3 - Third Order Intercept (2KHz Tone Spacing, 14.0MHz, 500Hz BW, Medium Preamp Gain, Delta 44 sound card) +26 dBm
Two Tone, Third Order Dynamic Range (2KHz Tone Spacing, 14.0MHz, 500Hz BW, Medium Preamp Gain, Delta 44 sound card) 99 dB
MDS (14.2MHz, 500Hz BW, Delta 44 sound card) -130 dBm High Preamp, -121 dBm Med Preamp
Minimum Tuning Step 1Hz
Direct Digital Synthesizer (DDS) Clock 200Mhz, <1ps RMS jitter
Max. Receive Bandwidth 48kHz (Limited by sound card)
Transmit Power 1 W or 100W HF versions 160-10m with optional amp (40W continuous carrier), 500mW 6m. Note: 1W models may be upgraded at a later date with the optional SDR-100WPA module.
Control Interface PC Parallel Port (DB-25 connector) or optional USB to Parallel adapter
Rear Panel Control Outputs 15-pin "D" connector for external amplifier and band control relays
Input Controls PTT foot switch, Code Key, Microphone
Sound Card Interface Line In, Line Out, Speaker Out, Microphone In
Enclosure Dimensions 10" W x 9.5" D x 4.5" H (24.1cm x 25.4cm x 11.4cm)
Power Supply Requirement 13.8VDC @ 1.25A (Max) for 1W version. 25A (Max) with optional 100W PA



CONCLUSIONS:

I give this radio an easy 5 out of 5 stars overall.

After all of that procrastination and finally getting it to work/set up, it has been fun playing with all of the adjustments with the software. This radio is just different than anything else. If you are into eSSB at all; this is the radio for you. However, if you a into DX/contesting, CW, AM, FM, Digital, or just a conventional setup - the software has a dedicated transmit profile for these too. This radio is also fantastic for SWL enjoyment as well. The filters - and the panadapter screen that can be used to control them is easy, informative, and just fun to use.

A bit difficult to set it up initially; but definitely worth it. One negative is that the software learning curve takes some real patience and determination. Features, quality, and usefulness are extraordinary, unmatched, and unique. This is definitely NOT your Daddy's Swan Ham radio!

The FlexRadio SDR-1000 is no longer in production.
For further info, here is the link to the FlexRadio site:
http://www.flex-radio.com/products.aspx?topic=sdr1k
 
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Nice, well written review! I have thought about buying an SDR-1000 several times.
But, ended up passing on them. Instead, I bought a new Flex 1500 qrp radio. Very
fun to use and even with 5 Watts, it works pretty good. I want to upgrade to one
of the bigger models, but, I think I'll wait until the 6000 Series are out. If the user
reviews are really good, then prices on used 3000's and 5000's will drop. Right now,
they are still too high priced, even used.
The only reason I have not bought an SDR 1000 is because it seems people have
problems with them running Win7 64bit. And the requirement for a Parallel port on the computer seems to be problematic for some. More so, since most new computers do not have a parallel port. And it seems that Flex at one time offered a parallel port to
USB adapter that had special drivers. And most off the shelf parallel port to USB adapters don't work correctly with the 1000 and Win7.
What version of Windows are you using? And did your SDR-1000 come with the adapter?
trucker
 
Nice, well written review! I have thought about buying an SDR-1000 several times.
But, ended up passing on them. Instead, I bought a new Flex 1500 qrp radio. Very
fun to use and even with 5 Watts, it works pretty good. I want to upgrade to one
of the bigger models, but, I think I'll wait until the 6000 Series are out. If the user
reviews are really good, then prices on used 3000's and 5000's will drop. Right now,
they are still too high priced, even used.
The only reason I have not bought an SDR 1000 is because it seems people have
problems with them running Win7 64bit. And the requirement for a Parallel port on the computer seems to be problematic for some. More so, since most new computers do not have a parallel port. And it seems that Flex at one time offered a parallel port to
USB adapter that had special drivers. And most off the shelf parallel port to USB adapters don't work correctly with the 1000 and Win7.
What version of Windows are you using? And did your SDR-1000 come with the adapter?
trucker

Thanks, trucker - it was fun to write too.

I'm using the Windows Xp/32 bit platform with it. No issues at all. Not quite sure what you mean by 'adapter'. Would you clarify that - please? The only adapter I had to get was the Firewire adapter. If you mean the parallel port out of the radio, it has a parallel port to USB cable - which is what I use. There is a driver for it and it works with the Xp software. I'm sure they have a driver for the later Flex radios and Windows 7. The newer versions of PowerSDR '2.3.x' IIRC will run on 32 and 64 bit platforms with Windows 7. Might check the FlexRadio site for further info.

This is the first software defined radio that I've owned and used. This was their first attempt and a decent one at that. It is the wave of the future - IMO.
 
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robb....can these be used on 11 mtrs? dothey have opentransmiton all freqencies ? :confused:

Most of the standard versions of the PowerSDR issued by FlexRadioInc keeps that from occurring. The radio itself doesn't need to have a diode removed or a jumper soldered that keeps it from doing 11m. The lock is in the software itself. There is a pirate/hacked version of PowerSDR that will work on 11m and can be found on the net. It is a little buggy; but it works.
 
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Great review Rob, and the Radio sounded choice on Ten meters today.
Audio was nice and smooth, I wish I had a way to record audio out of the Mobile.
Excellent contact, that must have been 160/170 air miles between us from were I was at today.


73
Jeff
 
Great review Rob, and the Radio sounded choice on Ten meters today.
Audio was nice and smooth, I wish I had a way to record audio out of the Mobile.
Excellent contact, that must have been 160/170 air miles between us from were I was at today.


73
Jeff

Thanks, Jeff.
Too bad the 10m band did so poorly today - especially on Field Day.
I looked up that spot where you were TXing from. Worked very well! I kinda blew it when we were talking; I forgot to turn the bandwidth down to 3.5khz - it was set at 6.5khz wide!
Yikes!

Still on roller skates with this thing - I guess.

I should have used the record function on this radio and posted it up here. Once again, hindsight is 20-20. Maybe the next time for sure . . .
 
Are you going to be on-the-air today Rob?
This evening I am going down to the Valley, and if you got time, lets hook up on ten again, and do some testing ..... I want to change an antenna on my Truck and see how well it will work.
With the distance between us, it might be a good time to do it with propagation down like it has been.
Let me know.

73
Jeff
 
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Robb,

Can you do some tests with the radio on adjacent channel rejection and blocking? I've heard that this is one of the areas where there could be some performance issues with these rigs.

Just curious about your personal results.
 
Robb,

Can you do some tests with the radio on adjacent channel rejection and blocking? I've heard that this is one of the areas where there could be some performance issues with these rigs.

Just curious about your personal results.

Listening on 20, 40, and 80m CW, there can be many stations piled very close together, such as on Field Day (just a few days ago). The filters can easy isolate any one of them. Even if they are really close together, as was the case that day. Not a problem and actually a strong point.

However, if I listen to the CB band on 27.385mhz/LSB I will hear/see some bleed over from some 200khz away if someone is running an amplifier.

Not sure I understand what you mean by 'blocking'.
 
Not sure I understand what you mean by 'blocking'.

Blocking or receiver desense is when another transmitter close by, usually on the same band but a different frequency keys up and wipes out your receive.
 
Blocking or receiver desense is when another transmitter close by, usually on the same band but a different frequency keys up and wipes out your receive.

To be honest, that hasn't been an issue yet. There are a couple of Hams that I know about a mile and a half from me; and never had them blocking at all. One of them runs a KW too. Now if someone were to get closer to me than that and it happens; then I can say something about it. When the CB crowd with their amps on in the South Bay Area; I cannot hear them at all on 10m or any other band (almost never listen to 6m). If I am listening to the CB band/LSB, there is just one or two running power and a dirty radio that will bleed a few 100khz over from 4 miles away - as I said before.

I'm sure the claims of 'blocking' have been verified with this radio. But I would have to say at this point, that is the extreme and not the mean. If that is the only bad that can said about this radio; then that claim has very small teeth. Those that made this claim must have many Hams very close by. How often does that happen - in all honesty? No doubt on Field Day if it is at a large group setting it would have a problem. Since I live in a densely populated suburban area one would think that it should happen. But just not the case in fact as yet. Just not enough Hams around to verify either way.

IIRC, This claim is made because the filters in the Flex are digital/DSP and not using a hard-wired filter. So, it is a trade-off I suppose. One one hand, you have the versatility -or Flexibility- to move without restrictions. On the other hand, the purist Ham will object the desensing and receive interference if present. You just can't have both - at least not at this point of the game. Unless a re-design would add a hard/wide 5 or 6khz filter and then the DSP can control it within that given parameter. But even then, that would still be a trade-off that some would claim isn't enough or it doesn't work as planned. I say it works already, and one has to be aware of this limitation is all . . .
 
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I have the radio working in windows 10 32 bit with no problems and full transmit from 0 to 66Mhz
 

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