Flex 3000 Initial Impressions, An Early Flex-3000 (F3K) Review

This review gives the story of my initial experience with the Flex 3000, followed by the Good, The Bad, and the Ugly.

After viewing a video and doing some research on the new Flex-3000 Software Defined Radio (SDR) I decided to order one and see if it really is the big bargain that they're claiming, and if I could tell the difference between this receiver and that of my trusty Kenwood TS-2000.  The company offers a 30 day return policy, so I figured that there's not a lot to lose.

The box came after about two weeks with a middle of the road quality firewire cable loaded up with two ferrites(!), power cabling, a BNC to UHF adapter and a quick start guide.  Of course, with the surprisingly small radio as well.  Pretty much all you need to get going, minus a microphone.

Others have remarked that it took them quite awhile to get  their Flex software going, but it only took me a few minutes to be receiving after getting the hardware connected.  I did prepare by installing the Firewire driver in advance, and I'd already read the manual.

I also decided to use my Shure KSM-44 studio microphone with this rig, so I cut an old ethernet cable and used the diagram in the manual to wire it up (unbalanced) to accept the output from my mic preamp.  I actually created a small box with a PTT pedal jack, Mic jack, and fast/up/down pushbuttons.

So on a quiet weekday afternoon, I was at last tuning around; the receiver did seem pretty good, but this was not really a contest environment.  I decided that PSK would be a pretty good place to test its performance: psk signals are very narrow, of widely varying strengths, and often crowded together, overlapping at times.  Unfortunately the 20 meter band to Europe wasn't open, so PSK was not going to be too challenging that day.

In any case, to prepare for digital modes, I purchased the Virtual Audio Cable (VAC) software ($30 -with a 33% discount if your Russian isn't too rusty, and you know how to use a proxy server) so that I wouldn't have to rig up an interface between the radio and the computer to feed the sound back to my Digital software.

So after setting up VAC using a guide on the Flex KB, I was soon using Digital Master 780 to listen to digital signals.  I was starting to see that the receiver is a lot more stable than that of my TS-2000, and signals near high powered adjacent signals were much more copyable, where they'd normally fade into uncopyable on my TS-2000.

I also needed rig control though, so I downloaded com0com and set up two virtual null modem cables.  One connecting com7=>com17 and one from com8=>com18.  The CAT control on the PowerSDR software was set to use com7 and the Push to Talk (PTT) uses com8.  On the digital mode software, I use the other end of the virtual cable, so com17 is for CAT and com18 for PTT.  I used kenwood radio settings, setting the serial options to match what was on com0com.  I can't find the guide I used for this, but you can easily adapt the vcom guide for com0com if you prefer it.

With only a little playing around I soon had full rig control and PTT.  I was ready to make a psk qso.

The Good

I connected the rig to my A3S yagi and pointed it at Europe.  It was late afternoon on a weekday so I didn't have high hopes, and sure enough the band was dead.  I did however find a few South American signals, and was making DX qsos in no time with very good reports.  I even ragchewed with another ham using a Flex 5000!

My usual technique of controlling the power output on PSK is to turn the drive up to maximum on the rig, and use the volume control to manage the power output.  This makes for a much cleaner signal, as you're never risking soundcard overdriving unless you max out your volume.  This method worked well with the Flex as it had for the TS-2000, and I found I could put out about 70 watts maximum on PSK into my yagi.

The ability to view a huge chunk of the band over time (panafall mode) is magnificent.  You can really see where activity is at all times, you quickly learn the signature for each mode.  You can use your mouse wheel as a "tuning knob," or tune in a half dozen other ways, and personally I have no issues at all feeling in control of my rig, as other (presumably older) hams have complained about.  I would recommend running a second computer monitor however, you should always have the PowerSDR interface visible for an easier transition from a knobs & buttons rig.

Too bad there's no focus-follows-mouse mode in Windows.  It would make using PowerSDR a little easier in digital modes.

Besides the excellent receiver, the wonderful small footprint (mine sits squarely on top of my Palstar AT1KP), and the availability of online support are very good.  Flex really does "get the internet," they have done a good job of creating a community around their product.

Finally, the #1 selling point for me was that PowerSDR is GPL licensed.  So I can hack it anytime it annoys me.  However, regarding the software, I do have one little criticism.

The Bad

I consider the need to buy a $30 third party application just to keep things in the digital realm a deficiency in the package: it really should offer VAC style functionality out of the box, whether they buy out VAC's author or simply invest some more time in their own product.

I briefly evaluated other options, like Jack Audio Connection Kit, but to use something like Jack, it would have to be integrated in both the Flex software and the digital mode software.  It's hard to say how difficult that would be without giving it a good look, but it would add a lot of value to the package.  If I have a substantial block of free time I may try my own hand at adapting something like this, but for now VAC does the job admirably.

The only other thing that may create problems for people is the fact that you really need a high end computer for it.  I use a Shuttle SG31 with a built-in Texas Instruments Firewire card which is recommended by Flex.

The Firewire is probably the achilles' heel of this device.  It is a standard that seems on the way to be obsolesced in the future, and it's been flaky for me.  I had a "no such device" issue that required leaving the pc and the flex unpowered overnight before it would come back to me.  If that had happened during a contest I cared about, I'd really be displeased.  I'll keep another rig handy, just in case.

So on to the real beastly feature of my Flex:

The Ugly

My Flex-3000 is horribly loud when the fan gets going.  I mean obnoxious.

Because I do some musical work, including occasional digital recordings, I use Shuttle SFF computers which are typically whisper quiet and still very powerful.

So I was fairly alarmed when a noise like a diesel engine accelerating came out of my new Flex 3000 halfway through my first medium-power psk qso!  I was (and still am) worried that I was shipped a bad fan, because it sounds like a bushings-based computer fan getting ready to die.  Idle fan noise is about the same as a regular cheap computer.

The TS-2000, being my point of reference, has a nice smooth sounding fan that quickly scales down after it gets the finals cooled down.  Perhaps it's not entirely a fair comparison, because the TS-2000 is a big box and the Flex is a deliberately compact box, but if Flex offered a better quality (or larger) fan and maybe a clearer path for airflow it might be a more comfortable companion in the Shack.

The last thing I want is the noise of this rig in the background when I'm transmitting voice.

Summary

While I would like to drill a hole in my wall and put the Flex in the next room to avoid the noise, I think it's a keeper.  The overwhelming reason for this is the truly excellent receive.  The majority of the contesting I do is digital, and this rig really works excellently for these conditions.

The ability to copy a weak signal just a few hz away from a strong signal is priceless, so despite its warts, the Flex-3000 is in my opinion a very good value for the computer savvy ham.

Expect to do a fair amount of DIY in both software and hardware though to get off the ground.  I wouldn't classify it as a complete solution, but it certainly is what they sell it as: a way to get a higher quality transceiver at a comparatively low price.

PowerSDR, Flex-3000 and FlexRadio are trademarks of Flex Radio Inc, Austin TX.