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Flex 5000A

Discussion in 'Amateur Radio Equipment Reviews' started by k2cm, Sep 22, 2008.

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  1. WY6K

    WY6K Ham Member QRZ Page

    I finally got around to using the Flex 5000 for CW. It is a disaster. The keyer is unusable - I guess due to variable latency. So I used CWX mode and was able to run off a couple dozen qsos. However, the software stopped every so often - as many as 5 times in a brief qso comprised of rst and name. Right in the middle of a character it stops. So then you press the STOP button and then restart it and try to pickup where you left. In addition, the timing went nuts sometimes, running characters together.

    I was using the DX4WIN logging program. The SDR software usually stopped when I made some entry in the logbook. The %CPU meter never showed more than 45%. Still, it crashed.

    It is unusable on CW.

    The usual recommendation is to dedicate a PC to just the Flex. But this is not practical because you at least need to run the logging program. I had stopped all processes that I know to be non-essential, such as Disk Keeper and McAfee, Google toolbar, Google updater, all HP programs, and all update programs. So the only things running were: SDR and DX4WIN connected to the internet plus windows essential processes, except the indexing process, which I also had stopped.

    Something really needs to be done to make the system more robust in a practical PC environment. The keyer should, IMHO, have been implemented with a $1.35 microcontroller rather than using the PC or letting the PC interfere with the keyer.

  2. WY6K

    WY6K Ham Member QRZ Page

    On the plus side (regarding CW use) the receiver is a joy to use on cw when it is not crashing. I really like the filters - perfectly narrow and no ringing. I found I used the 100 hz filter most of the time. After a while, 250 hz seems absolutely wide!

    I also like tuning with the mouse. It is wonderful to see a spike (QSO) on the spectrum scope then click on it and you are there instantly!

    That part is really good.
  3. WA2DTW

    WA2DTW XML Subscriber QRZ Page

  4. VE4KV

    VE4KV QRZ Member QRZ Page

    I'd be curious to know if the 5000C somehow has been factory optimized and
    if it has or doesn't have these issues ?
  5. K3ROJ

    K3ROJ Ham Member QRZ Page

    I got my 5000A

    Aha, at last my problems are solved with the Vista 64 Bit problems. Flex Radio just released a new Power SDR console Version.1.16.2, the Flex 5000A Firmware Version and 5000A driver Version Wanting to keep my shack somewhat compact, I had bought an ASUS Assentio computer Duo Core X2100 processor Windows Ultimate and 4 GB RAM and of course running Vista 64 Bit. The ASUS also has HDMI output to supply outstanding video to a TV monitor in the future. My 5000A now runs flawlessly with this $600 computer and puts a great display on an LG 22 inch monitor. One thing I did do is turn off the automatic updates such as the AVG anti-virus and Microsoft. All unecessary programs were uninstalled along with most nuisance startup software. At first I disabled the LAN but found it necessary for logging since we have QRZ automatic lookup and the computer has yet to freeze up or burp. The Ham Radio Deluxe runs fine alongside the Flex software and have no complaints with it yet. I was really frustrated at first not being able to use my Vista computer but Flex came through as promised. The problem is using third party software such as VAC (Virtual Audio Cable) which is necessary to run Digital modes and have to defeat the "Turn off Signed Driver Requirements" or hot the F8 key when booting up to do so. Waiting for my 30 watt 144/432 transverter unit which will fit inside the 5000A. Didn't order the 60 watt units since it would require boxing the 5000A up and sending back to Flex Radio so they could install a necessary power connector since the Flex's supply wouldn't be able to handle the additional amperage. Besides, I would miss my 5000A too much to let it out of my sight for possibly 2 weeks.
    Last edited: Feb 19, 2010
  6. K3ROJ

    K3ROJ Ham Member QRZ Page

    My words exactly

    Fast computers are getting cheaper and found an open box HP 4 QUAD at Best Buy for $399. It had integrated video on the mother board so bought a new graphics card and 500 watt power supply and installed them myself. The unboard firewire 1394 worked fine as is. (The ASUS DUO QUAD PC will now be used for video editing since it is fast enough). I never dreamed I would enjoy a transceiver as much as the Flex 5000A and use a good mouse for tuning instead of the powermate option. The new graphics card enabled me to use dual monitors to display the SDR console, MixW software, N3FJP logging etc. which the 4 QUAD handles without burping. Believe me when I say it is a learning curve when first getting this transceiver but it is well worth it since now I can discuss computers with any computer geek--Maybe.
    Last edited: Feb 19, 2010
  7. KU5Q

    KU5Q Ham Member QRZ Page

    That's great. Sounds like an impressive technical background. I don't have any of the Flex Radio products. I'll bet you'll have some comments regarding the following;

    As far as decent receiver performance (e.g. effective blocking dynamic range, and much less 20KHZ, intermodulation by the undesired signal (IMD DR3), etc...., wouldn't it seem that rcvr multiple conversion designs are about as optimzed as they will be as far as the current "ham" offerings go, with folks like Ten Tec/Elecraft? In my collection, among others, I have the Orion II, and the K3. Both very good, but even with the twist of DSP, and selective first stage filtering, and the obvious compromises in this type of design, which the basic design is not cutting edge, perhaps limits have been reached here.

    Without "digging too deep" yet, I think Flex's approach is interesting from what I can tell, with the incoming raw RF split into two mixers fed by the local oscillator with two outputs in quadrature, converted to base band, and fed into two analogue to digital controllers (ADC) which then make up the "in phase", and quadrature/90 degree channels for processing but done digitally! Less components, and less contribution of intermodualtion distortion. And, the filtering just before the ADC limits the signal above the Nyquest frequency, with that extra power folded back into the passband.

    Still some rough edges for sure. Even though the direct conversion thing is not new, cheaper processing hardware, that is sure to come with time will trickle down to the public, and hopefully be able to handle the necessary algorithms/sampling rates.
    Last edited: Aug 21, 2009
  8. WB2WIK

    WB2WIK Platinum Subscriber Platinum Subscriber QRZ Page

    One problem with the design, though, is if the signal does not go through A:D conversion without being distorted to begin with, then artifacts from distortion products cannot be eliminated.

    That was precisely the problem with the SDR1000 I had (and no longer have); it could not handle very strong out-of-band signals (which is truly a function of linear circuits and filtering prior to DSP) and my local 1.25 MW SW BC station overloaded it, creating artifacts that no amount of digital processing could remove, because at that point it was too late to do it.

    My 31 year-old TR-7 doesn't have this problem, and I could hear thousands of weak signals adjacent to KVOH that the SDR1000 on its best day could not even tell were on the band.

    Possibly the 5000 is better, haven't tried it yet, and I'd like to.

    Once you've been stepped on by a 10,000 lb elephant, you can use all the digital processes in the world to get out from under it, but you're already flattened.

  9. KU5Q

    KU5Q Ham Member QRZ Page

    Are you sure?

    Are you sure?

    So, who's got it wrong you or, Flex. Are you sure you "understand the technology? :p

    From: Perry, Terry
    Sent: Friday, August 21, 2009 1:26 PM
    To: ''
    Cc: 'Matt Youngblood'; 'Greg Jurrens'
    Subject: RE: Flex Direct conversion receivers

    Thanks Gerald. I’ll pass this on to the complainant.

    All the best to you,


    From: Gerald Youngblood []
    Sent: Friday, August 21, 2009 1:21 PM
    To: Perry, Terry
    Cc: 'Matt Youngblood'; 'Greg Jurrens'
    Subject: RE: Flex Direct conversion receivers

    Hi Terry,

    If overload were a serious problem for FlexRadio, we wouldn’t be in business and gaining market share as we are in a very bad economy. In fact the government is buying receivers from us because our architecture delivers such high dynamic range at low cost and low power.

    Take a look at the Sherwood Engineering site to see how the FLEX-5000 and FLEX-3000 stacks up as one of the top performing radios ever made. Also, take a look at the July 2008 review of the FLEX-5000 in QST magazine to see their measurements.

    Here is Sherwood’s comparison:

    Also, here is a graph that Russian hams did to show the in-band, two tone, 3rd order dynamic range comparisons at 200 Hz spacing.


    Inserted from <>

    Hope this helps dispel the myths.


    Gerald Youngblood, K5SDR
    FlexRadio Systems
    13091 Pond Springs Rd. #250
    Austin, TX 78729
    Phone: 512-535-4713

    "Tune in excitement!" (TM)

    ---------- Forwarded message ----------
    From: Perry, Terry
    Date: Fri, Aug 21, 2009 at 10:02 AM
    Subject: Flex Direct conversion receivers
    I'm familiar with the old basic direct conversion receivers. I've been keeping my eye on Flex, and I really like what they are doing. However, I've never owned any Flex model transceiver. I understand that Flex uses the Quadrature Sampling Detector very successfully. I've heard comments from those hung up on the older "tried but true enough" multiple conversion with roofing filter in the first stage I.F. receivers that the Flex rcvrs (especially the 1000) fold up in front of close, strong (as in several KW) broadcast AM/HF signals, as opposed to something like one of the old Drake R4C's.
    I have a suspicion the supposed complaint may be "a lot of hot air" from the obviously biased complainant, but since I don't have a Flex to try out myself I can't know for sure. Seems if overload was a serious problem with the Flex radios, we hear more about this, and since I haven't, that makes me even more suspicious of the complainants’ remarks.
    I'm very much hoping folks on this reflector will comment with their experience, and most importantly to me, some hard technical information to refute the overload complaint.
    Thanks, and look forward to replies.
    Last edited: Aug 21, 2009
  10. WB2WIK

    WB2WIK Platinum Subscriber Platinum Subscriber QRZ Page

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