Technical FAQ

Q. What is the frequency range?
A. 64-1,700MHz, although straw poll tests on pre-production units indicate that units can be stretched down to 51.5MHz or so. Upper frequency limit is beyond 2,000MHz. In testing, we have determined that there is a gap between about 1,100MHz and 1,270MHz where the design of the local oscillator VCO, PLL and divider chain in the tuner chip don’t provide seemless coverage.

Q. What can the FUNcube Dongle receive?
A. The FUNcube Dongle has no restriction on modulation schemes: it is limited only by the application program running on the host computer. As long as the signal fits within about an 80kHz bandwidth, the FUNcube Dongle is capable of receiving the radio signal. So, for analogue reception, as well as narrow band FM and SSB, it is also possible to receive, for example, sound subcarriers for TV broadcast. Similarly for data reception, as long as a data demodulator has been written that will accept standard soundcard quadrature I/Q reception, that will work too.

Q. What is the bandwidth?
A. 96kHz is the quadrature sampling rate. Once the ADC’s decimation filter skirts have been taken into account, you have about 80kHz.

Q. What applications work with the FUNcube Dongle?
A. As well as the forthcoming FUNcube front end application, any application that understands a standard stereo soundcard configured for quadrature, or I/Q, reception should work. Examples include Linrad, Spectravue, Rocky and M0KGK.

Q. What is the sensitivity?
A. Each unit is tested for 0.15uV for 12dB SINAD NBFM at 145MHz and 435MHz.

Q. What operating systems are compatible?
A. Currently Windows 2000 SP4, XP 32 bit, and Vista and Windows 7 32 and 64 bit have been tested. The sound card element works with Mac OSX and Ubuntu 10.10 32 and 64 bit, but the frequency setting application has not been ported yet.

Q. What’s the difference between versions?
A. There are two versions, the Base and the Pro models. The Base model is frequency restricted and designed as an entry level minimal cost device, targetted for educational outreach. The Pro model is unrestricted in its frequency coverage.

Q. Can I upgrade a “Base” version to a “Pro” version?
A. At present, the upgrade will require a return of the device so that it can be modified to accept “Pro” firmware.

Q. Is the firmware upgradeable?
A. Yes, already the devices can have their firmware upgraded in a matter of a few seconds by the user. However, Pro firmware and Base firmware are not interchangeable.

Q. Do I need front end filters?
A. Some people have experienced front end overloading with the FCD at VHF in particular. Although there is fixed and programmable front end filtering already on the FCD, at VHF it’s not very selective. Typically the symptom is that it will appear deaf: this is the noise floor rising due to an overloaded front end. You can see this in Spectravue as when you plug in the antenna the noise floor rises potentially several tens of dB. Although reducing gain can help, of course innevitably this is at the expense of the unit’s native sensitivity. At this stage it is worth pursuing external filtering options. We’re working on some solutions already, but some readily available commercial solutions include Hamtronics’ LNP preselector, SSB Electronics SP-2000, and DCI’s DCI-145-2H and DCI-145-4H. As these are not exactly cheap, I have been working on some ideas here that you may like to try: We’re also investigating at a reasonably priced active no-tune solution.

Q. I am having trouble upgrading the firmware. What can I do?
A. The most reliable way to do this is from Windows. It is essential that, after placing the unit in bootloader mode, any other software that might access the FCD is shut down before you attempt to update the firmware.

Q. What support options are there?
A. You can email me using my Paypal email account, or alternatively there is a very active FUNcube Yahoo group that often provides answers more quickly!

550 Responses to Technical FAQ

  1. RD3BCH says:

    The remarkable idea and very nice price! There is one question – a bandwidth this receiver about 80 kHz. My the sound card provides 192 kHz. Whether there will be a possibility to inferred from the device a signal before ADC (for example 2.5 mm stereo jack)? In the street and with notebook internally ADC, and dwellings in stationary conditions an external sound card with wide bandwidth. Excuse for bad English and repeated post.

    • admin says:

      The restriction of bandwidth is twofold: to keep costs of the unit down, and that technically speaking, 192kHz codecs frequenctly have decimation filters with skirts well before Fs/2 at quad rate for the ADCs. I’m afraid that there is no stereo jack provided. The signal internally is also differential to maintain a decent SNR.

      Howard (G6LVB)

  2. David says:

    Is there an indication of maximum allowable length of USB cable between the PC and Dongle over which reliable operation can be maintained? Guess you’ll see where I’m going with this.

    • admin says:

      Hello David

      Theoretically 5m is the limit without hubs. I believe that you can run up to three daisy chained hubs with up to 5m between them each. You may have seen “active” USB extenders. These are essentially one port hubs. I need to test this theory though! So you could run up to 20m and still be within specification. I’m afraid I’m not at home at the moment and much of my stuff is in storage so to get a definitive answer might take a while.

      But yes, I understand why you would ask the question! I’ll let you know the answer just as soon as I can.


    • admin says:


      I have tried with a daisy chain of three hubs with 5m between each plus a final 5m passive (total 20m) and this works. Only the first hub was powered. It may be that it would work completely bus powered if nothing else is hanging off the daisychain. Strangely, also a 10m fully passive worked, but that is not recommended here:

      To add to my previous remarks, it appears from the USB spec that you can daisy chain up to five 5m “active” segments plus one 5m passive giving you 30m, or near enough 100 feet.

      The FCD is a USB 1.1 device running at full speed (12Mbps). I am trying to drag an old laptop out of the dust with a USB 1.1 port on it but it only has 64MB RAM and thus only barely supports Windows 2000 let alone XP. The FCD is recognised but now it’s struggling to find some driver components, sso it needs a bit more time on it. I’ll see if I can get it to work on a fully USB 1.1 port at some point.


      • admin says:

        Well, it looks like it works on USB 1.1 on Windows 2000 SP4 too without any extra drivers! Even though I say so myself, the choice to use HID and a standard USB audio interfacess has had quite a lot more benefits than I originally anticipated.

        Also, it identified a bottom line for CPUs: Spectavue was starting to stutter a bit on the 233MHz Pentium in the 11+ year old Toshiba Libretto 110CT I was using – with only 64MB RAM. But it worked!


        • David says:

          Hi Howard,

          Thanks for the info and you’ve answered the Version number/speed question I was about to ask. Been looking at USB extenders of which there are quite a number ranging from cheap to extortionate. Anyway, it opens up a number of possibilities.


  3. Ronen says:

    Hi again
    Will this software
    work with the dongle ?
    Please Advice
    Ronen – 4Z4ZQ

    • admin says:

      Hello Ronen.

      Thank you for your question. I am open to correction on this, but n first looks, Signals Analyzer appears not to be real time: instead it seems to take a .wav file and allows the user to analyse the data retrospectively. Certainly it would work with .wav files recorded directly from the FCD.


  4. Mike says:

    Hi Howard,

    A question about the strong signal handling high pass filter design: is this a future modification to the already in production units?

    • admin says:

      Hello Mike

      The HPF will be included on the production models although it will be yours truly doing the mod. It’s a pretty simple procedure retrofitting a couple of chip caps and inductors. There is also a minor firmware change that will be included.


  5. Stephen - W9SK says:

    What are the sensitivity & noise specs for FCD? Any any specs or measurements posted elsewhere on your site?

    • admin says:

      Hello Stephen.

      Thanks for you note. For standard NBFM, we target 0.15uV for 12dB SINAD on 2m and 70cm.


  6. Wilhelm Hombach says:


    which software do you recommend for Windows 7 64bit??


  7. Peter J Francis says:

    Hello Howard,
    I’m one of the lucky few that ordered a FUNcube dongle yesterday which I am really looking forward to getting.
    I have one question , what type is the antenna connector ? (This is so I can make sure I have the correct one ready when it arrives)

    Thanks for all your efforts with this , I’m sure it has taken over your life to a certain extent.
    73’s Peter G7MMW

  8. Andy says:

    Hi Howard,

    Just got the FCD up and running, tried 3 differnent SDR progs currently using winrad, all show a large spike at the centre frequency about 40dB above the noise floor, cannot find any way to get rid of it. Also noise floor seems high even with no antenna connected, tried different gain settings, can you offer some advice please?


    • admin says:

      Hello Andy

      This is the zero IF. With all zero IF receivers, including the Softrock there will be some DC offset. There should be an option in your SDR software to null this out. Spectravue has it in the SoundCard IN Setup menu item.

      With no antenna connected, using Spectravue and pressing the “Defaults” button on the FCD controller software, you should see around -105dB noise floor. The “Defaults” button sets the gains on the device to some sensible settings optimised for optimum sensitivity.

      I was trying to get these defaults into the firmware before release but I felt that it was better to use solid firmware (the firmware you have has been static since October) with a simple button press from the front end rather than risk a rushed firmware release.

      Regarding DC offset, and also image rejection, as well as being able to optimise this with your existing SDR software, the next firmware release has this integrated into the FCD as well so it can be done on the FCD or in your host software (or both!). The benefit of doing it on the FCD is that DC offset and image corrections can be made to be frequency specific. I believe it will also be possible to perform a better null as the resolution is higher than some host software.


      • admin says:


        Also see my notes here:


        • Andy says:

          Hi Howard,

          I found in spectravue pressing the NCO Null button got the spike down quite a bit, I also tried the soundcard in adjustment but can’t get it any better than 20dB above the noise floor.

          With regard to the noise floor I got it lower by going into the recording devices menu in windows, selecting the FCD and turning the level down to 1, the adjustment seems very course, 0 of course shows nothing, 1 shows the floor at about -110dBm, the scale goes from 0 to 100, the device shows as a microphone in windows 7 x64 is that correct?

          Will continue playing, its great what such a small device can do!!


          • admin says:

            Hi Andy

            I’m away taking the evening off from Dongling, but a couple of quick comments.

            Firstly, the resolution of zeroing the DC offset on Spectravue isn’t as granular as it could be. It may be that other SDR software might have finer resolution. To whet your appetite, the next firmware release will have dc offset and image rejection controlled on the device, and the host software will also allow you to adjust with frequency.

            Secondly, I will have to take a look at thus on my Windows 7 x64 box but I suspect that reducing the recording level will reduce sensitivity.

            In SDR it’s quite common just to avoid the area around 0Hz. However this does not stop you demodulating unless it’s a really weak signal. For example you can demodulates a wide band fm signal that spans the entire passband over the zero Hz. (If you try demodulating WFM you will find that it distorts as the 96kHz isn’t quite wide enough, but it’s perfectly readable).


          • admin says:

            Hi Andy

            Reply number 2! I have had a chance to put this on my W7 x64 box. It’s a bit fiddly as the test set lives in the shack and the W7 x64 box is my media centre in the living room. Anyway, I ran 15m of USB extenders and tested it.

            Sure enough, you are right. It also looks like setting the level to 1 is about right too, and there is no degradation in sensitivity either.

            Yes, it does appear as a microphone. It’s a long story, as originally it was set to be a USB Audio satellite receiver device but I changed it to being a USB Audio microphone device while chasing another fault and never changed it back again. This won’t inhibit your listening pleasure, it’s just a semantics thing.

            Anyway, thanks for the heads up. I hadn’t noticed this before, I’ll check under Vista too, that might do a similar thing.


  9. What about a LAN conecction instead of USB ? I would be even better…! there are some cheap microcontroller solutions in the market. Maybe in the 2.0 FCD ?

    Nacho, EB1GER

    • admin says:

      Hi Nacho

      I will put that into a wish list, but in front of that I already have higher bandwidth (in the MHz). Neither are simple modifications, they’re both quite fundamental re-thinks. I also don’t think at present either will fit in the Dongle package, it was quite a squeeze as it was.


  10. Dr. Robert Suding says:

    Hello Howard,

    In case you don’t remember me, I made the executive decision to give the last available Tracker Jr. to you instead of the Australian Ham. My wife sold you the last one and I had sold it to the Australian. I had to really scramble to get another Tracker built and sent out to the Australian Ham before he got home. I guess it worked out OK..
    I suppose that you will be including a virtual Tracker JR in a future version of the FCD. Should be rather easy to implement. I think you made the right choices on the FCD, except that you need to have a used small scale automatic building machine doing the tedious operations, or you and your helpers will soon go nuts! LOL, as the kiddies say.

    Satellites stopped being fun for me after the demise and non-replacement of AO – 40!

    My ham operations these days are on PSK and the digital derivatives. A well designed User Defined Radio running about 40 watts on 20M, 40M and 30M (priority order) in a “Super Dongle” box with a nice big free spinning weighted main tuning knob and ~four 300 degree nice small knobs and an IPAD like screen showing the calibrated spectrum, frequency and only the needed setup interactions, and IPAD-like finger controlled inputs.

    Overall input and output priorities and “knobs” and “switches”, by type, function, and position must always be definable by the user. My own input priorities would be Memory Recall, Knobs & Switches , Finger Inputs, Voice Control, Keyboard, and in last place would be a mouse.

  11. Christian EA4EUN says:

    Hello. I have all day testing the FCD Pro and reading other users messages. I updated it to the latest firmware.

    Now is running the WRPlus 1.04 but only I´m listening noise. I read the FAQ but I don´t know what´s wrong. Also I tried to receive data in the local aprs frequency with Mixw software + WRPlus. No data but I can listen sometimes the packets sound mixed with noise.

    Please help me…

    73, Christian EA4EUN

    • Matty MD0MAN says:

      Hi Christian,

      Select a local repeater frequency.

      Using WR+, you should be able to see images / speech in the waterfall, select FM and click on the data on the waterfall.

      You should now be able to hear the audio.

      Depening on the operating system you are using, you may need to lower the gain from the FCD.

      Other users have had to do this in Win7, I have also had to drop the audio on the level from the FCD to get good results in Vista.

      If you have Vista:-
      ‘Right click’ on the speaker icon next to the clock display, select ‘Recording Devices’ – this will open a new window.

      Select the ‘Microphone, Fun Cube Dongle, click on the ‘Levels’ tab, and set the slider to 1.

      This gave me much better sounding audio.



      • Christian EA4EUN says:

        Hello Matty. I´m using Win XP SP3 in an Asus Eee PC 1000H netbook (Intel® Atom N270 + 2GB Ram)

        Well. Now I´m receiving data on the waterfall but with no noise.

        I will continue checking the sound card and FCD config, before to try to receive telemetry from CubeSats. Maybe I need to look for a better antenna too.

        73. Christian

  12. Zoulou Whisky says:

    Hello Howard “Twezzer hands”,

    I’am # 117 FCD proud owner.

    I did hooked up a sat dish LNB for the Ku Band to try to pickup satellites
    signals with the FCD like I successfuly did before with my Icom IC-R1500, but they are not showing on the SpectraVue screen quite like they did with the Icom on the Spectran screen…

    Is it because the FCD itself and do I have to enter differents settings in the FCD
    frequency control in order to get better results ?

    I must say that I always put a DC block before the FCD antenna input, of course.

    Thanks for your advice, and keep up your awsome work !


    • admin says:


      I suspect that the levels will almost certainly be different, you may wish to adjust the gain, either with the FCD frequency controller or in Spectravue, or indeed both.


      • Zoulou Whisky says:

        Hi Howard,

        It seems like my FCD is kind of deafth (or blind…) between
        780.0 Mhz and 1265.0 Mhz (approx.)…

        It’s even not able to receive pagers signals in the 900 Mhz !!

        That would explain why it is not working as expected with
        the LNB, witch output is between 950 / 1450 Mhz.

        I know that there is suppose to be a kind of gap somewhere around 1 Ghz, but since I run the firmware to my FCD, it seems to behave differently than before.

        Could it be brought back to the original firmware somehowe ?


        • Mark N8MH says:

          Hello Zoulou, (heh)
          You can download the orginal firmware and flash it:

          Howard is aware of a gap introduced in ver 18c that was not present in 18c; we can expect that he will fix that in the next release.

          • admin says:

            You beat me to it!

            Yes, I made a typo when I rushed out the 18c firmware. It was pushed out primarily to address the automatic settings of the “Defaults” and to improve VHF strong signal handling by choosing better filters.

            It also already had some other changes in it to support more granular frequency settings, and this broke the setting of frequencies from about 660MHz to about 1GHz due to a typo on my part. Apologies!

            As Mark states, reverting to the original 18b firmware will get you back.

            Firmware 18d with this fixed in it and a tranche of other updates, primarily aimed at opening up the full API, but also including IF RSSI feedback to front ends and DC/IQ correction on the device itself will be available imminently.


        • Gentelmen Your were right, and I thank you very
          much for your help !

          The problem is solved, as my FCD is back to were it was
          and it’s now receiving signals around 900 Mhz +/- so
          I expect to be able to use those LNB in order to explore
          the spectrum in the Ghz’s…

          Cheers !!

  13. Augusto says:

    There will be in the future a way to have the lower band limit go down to 48 MHz or so ? I am thinking by now to an “up-converter ” but the less hardware, so better!
    tnx 73 de Aug HB9TZXA / I2JJR

    • admin says:

      Hello Augusto.

      It is a limitation of the VCO and PLL on the tuner chip. I don’t believe it can be rectified in software.


  14. Peter says:

    Hi all, Why I can’t see the mic gain in record devices selecting the FCD using WinXP? In Vista I can see (and adjust) the mic gain for the FCD.
    Any suggestions?

    • admin says:

      Hello Peter

      There is no such option in XP. The sound driver model was changed in Vista so things work a little differently. Is there a reason that you need to change it?


  15. Mike says:

    What is the frequency limit of the FCD?

    I have come across a potential problem with WinRad and its deviants. These all use the ExtIO functionality for control, these use a 32 bit signed integer to set the frequency. That means the frequency can not be greater than about 2.14GHz. I know the FCD limit is nominally 1.7GHz but I understand it does better than this and would be interested in what people are finding the limit actually is.

    The FCD itself uses unsigned 32 bit numbers so it is numerically limited to 4.3GHz, which with the current hardware is no problem.

  16. Dick says:

    I’m trying to run SpectraVue in Windows XP (under VmWare on a MacBook Pro) and have FChid.exe running. FChid recognizes the Funcube; but when I click the “set frequency” button with the frequency entered to almost any value, I get an error message saying: “Target frequency must be between 50000 and 2500000”. I’ve tried entering values of 145000, 147500 and 50000 and still get the same error message.

    In Spectravue I’ve been trying to set the center frequency; but I’m not sure how to set things up to work with the dongle. I have the input device set to sound card and the sound cad input set to FunCube Dongole v0.0.. The sample rate is set to 96000 and the BWlimit is set to 96000. The center frequency is set to 1475000.

    I must be doing something wrong.

  17. Pierluigi says:

    Hello everybody,

    I hope to be in the right place to post…

    Friday I received my FCD, #246! I was happy and curious of course. Yesterday I would test it a little at the bench before to go out in the cold to do “real radio”.
    The problem I fight all the day, is that the FCD goes into
    “bootload mode” every few times I change the frequency or other parameters on the FCHid panel. The trouble is random.. but it’s getting worse and worse as more as I use it! Yesterday I could work for a while, some time at the second change, I got stuck.
    To recover, I have to unplug the FCD for seveal minutes and sometime also reboot the PC.
    Often, when I plug back the FCD, it seems to work with Spectravue, but as soon as I launch the FCHid application, it switch to “bootload” mode.. no explanation!

    I’ve experienced that with both my laptops with WinXp and both firmware 18b and 18c. No changes…
    At the end of the day, I got frustated.. and fully stuck! I believe that must be something wrong on my own setups.. it could’nt be so bad by itself!

    The testing environment is clean, no RF in the shack. I triyed also this morning in
    portable.. no way! Very often when I launch the FCHid, the device switch to “bootloader” mode, for no known reasons! Almost impossible to operate!.. 🙁
    Anybody here could give some tips about?
    Many thanks to all!

    Vy 73!

    • admin says:

      Hi Pierluigi

      I believe you have a hardware fault, I have priority air mailed you a replacement today (Monday).


  18. Antonio Pilichi I5NQK says:

    Hi Howard,
    I have a similar problem.
    Often the Dongle is in “booatload mode”. Sometimes it works (but random) and it communicate with the program to set freq. But, random, I listen the “disconnection” sound of the periferical in Windows and no response from Dongle. Sometimes I connect the Dongle into USB and I listen the first sound and immediatly another disconn sound. When it works I can listen the signal but with a great Voltage. With a Test Set I see a trace with a 100 mV, for example. Sometimes, moving SMA, I receive a good signal and a good trace with a very little sig. (0,15 microV). Excuseme for the great disturb with my questions. 73 and TNX again for Your work.
    Ciao from Italy 😉

    • admin says:

      Hello Tony

      Thank you for your explanation.

      Where and what are you tracing at 100mV?

      I have two suggestions!

      When it is not working is it saying “Bootloader” in fast CW? Does it happen while the FCD is plugged in? Is there physical movement (while it is plugged in) that make the FCD go into bootloader mode? If so, a quick fix may be simply to clean the USB contacts with some isopropyl alcohol and do five or six rapid insert/remove cycles.

      In addition, it might be worth just trying the prerelease formware that has an increased timing when hard resetting the tuner chip. please note that this is an early release of 18d code so there are some other things that need fixing, but it might help do diagnose if there’s another problem.


      • Well Howard and TNX.
        Actually I am not able to set any command using FHHid (Succed, FCD Found… HIDSetFreq of 99988 returns 0… Error, FCD frequency NOT set.). I have used FCHIDBL for export18dpre. All OK but FCD not works. I have cleaned the USB contacts with isopropyl alcohol and the rapid insert/remove cycles… NOTHING.

        I am not able to do other… and I have the fear to damage the dongle more.
        Now, I repeat, I am not able do give any command…

        Is possible, for You, if I ship the Dongle, to check it ?
        I know that your time is precious, but I do not know what to do.

        Many thank You.


        When it is not working is it saying “Bootloader” in fast CW?

        Does it happen while the FCD is plugged in?

        Is there physical movement (while it is plugged in) that make the FCD go into bootloader mode?

        Excuseme again.

  19. BANKO Darko says:

    Was für ein software muss ich haben ( Source ) um denn FCD benützen zu kennen ?
    Darko OE7DBH

  20. Declan says:

    Hi can the dongle be used as a scanner with some kind of third party software, like for example could i store 100 memory channels and let it scan through them etc…

  21. Rob says:

    Hi Declan
    Not what the FUNcube dongle was intended for but there is software available at the yahoo group that will allow storing of frequencies in WRplus,using ExtIO.dll files.
    The FUNcube dongle software is at a very early stage of development.
    So yes you can,but it’s never going to be a AOR,but for the price you can’t go wrong.
    All mode, 64-1,700MHz
    Rob M0TFO

    • admin says:

      To add… if the host software is written then it can behave in this manner. I am sure in time such an app will be developed.


  22. radio b says:

    Hello, nice job done, congrats..
    Is there a room to add a spectrum analyzer in your SW, so the dongle can be used also as a low end instrument. The technique of scanning parts of the band, memorising, combining and displaying onthe screen should maybe work..

    • admin says:

      We’re anticipating initially that people will add VFO code to existing spectrum analyser software rather than the other way around, and that is already happening. For the FUNcube satellite telemetry receive software we’ll have a spectrum view.


  23. Stefano - ik2oyd says:

    Hello Howard,
    I’ve received the dongle #199 on 25 Jan at noon, nice job!
    One question: with firmware 18dpre it is impossible to null image of signal generator at 100,01MHz with Spectravue I/Q balance settings and the image level is higher in respect to real signal at right side of DC zero (offset: 10KHz), after reload of 18b firmware I’m able to obtain the null of image. It is a 18dpre bug ?


    • admin says:

      Hi Stefano,

      This is not production code. I need to take a look at the I/Q correction, I am aware of some other comments about it.


      • Augusto says:

        Hi Stefano ik2oyd,
        Congrats for the FCD#189 ! I’ll try again oncemore , hope to be able to “win” one ….. Glad to find you and maybe Al kbd here!
        Ciao, 73 to QRA , Augusto i2jjr ecc

  24. Chris VK6KCH says:

    Hi Howard,

    This is great stuff! I would definitely like to get one fro the next batch.

    Interestingly, a standard “C band” commercial LNB (such as an NJT NJS8486EN or a Norsat 3120N) would provide an inexpensive way of receiving in the Amateur Satellite band from 3400 to 3410 MHz. With a high-side injection LO of 5150MHz, these devices would output an inverted image of a signal at 3405MHz at an IF of 1745MHz.

    Similar approaches could be taken for essentially “off the shelf” LNBs for other bands, including 2.4GHz and 10GHz. These LNBs typically require a DC supply fed up the coax of +19VDC at up to 350mA; this would have to be provided via an external DC Bias-T. However, some of the LNBs (the more expensive ones) also require a 10MHz (sine wave) reference signal up the coax, at around -10dB to 0dBm. Do you have a 10MHz clock available within the FCD, and if so, would it be feasible to multicouple that reference onto the coax inner conductor?



    • admin says:

      Hi Chris.

      The reference oscillator is 24.576MHz and that is used throughout the device, in particular to derive the 96kHz sampling rate – in fact that pretty much dictated the crystal frequency.

      So in short, sorry, there is no 10MHz reference in there!


    • Jose EB5AGV says:

      Hi Chris,

      Does that 10MHz signal need to be phase locked to the receiver reference (I guess not)?. If this is not the case, there are plenty of ways to get a nice 10MHz signal, from internal oscillators in test equipment (lots of them ovenized), to GPS controlled oscillators. Of course, having it into the FCD would be a plus but, well, we can’t have everything inside this wonderful package 🙂

      73 JOSE EB5AGV

  25. KA9Q says:

    What does the response look like around zero output frequency? Most direct conversion receivers have serious phase noise problems so close to their local oscillators. Is there a high pass filter after the mixer that creates a notch around the center frequency?

    I am trying to decide how to best use this on the ARISSAT-1 downlink. If it could be carefully tuned to track Doppler, then the Funcube’s 0-frequency notch would land on the satellite’s own and there wouldn’t be a problem; the Funcube would capture the entire satellite passband.

    If the Funcube were statically tuned, I could track the Doppler on the BPSK beacon fairly easily, but the +/- 3.3 kHz shift around the nominal 145.98 MHz passband center would eat into the upper end of the linear translator section between AOS and closest approach. It would eat into the FM channel in the upper half of the transponder between closest approach and LOS, but that seems less of a problem since there isn’t much FM sideband energy there.

    It would still be best to have the Funcube either closely track the passband or push it off to one side so the 0-frequency notch would be out of the way. In that case I probably couldn’t capture the entire transponder output, with Doppler, with the Funcube.

    • admin says:


      Sorry for the delay in replying, you caught us while preparing for a sale weekend which is innevitably rather frenetic. It may be I answered your question regarding phase noise in another private email, but if not I have placed some information here:


  26. lloyd vandervort says:

    HI , I am having fun with my new dongle.
    It does have some desence with strong local pagers in the 450mhz band.
    A filter or trap corrects this.
    Is three an easy way to have winradplus to directly tune the dongle ?
    Lloyd N9RPU

    • admin says:

      Hi Lloyd

      I believe that WRplus and winradplus are the same thing. There are some guides on this written by David Barber on the downloads page.


  27. Angelo says:

    Hi Howard,

    for education purpose, to show it in a classroom during a presentation, could be possible to have a block diagram of the device when you will have some time for this?

    Tnx, 73 de Angelo IK8VRQ

  28. Rolf says:


    How is the link to the user group ?

    Nice regards

    de Rolf

  29. Does anyone know how fast I’ll be able to change frequency when tracking Doppler? I have an application that is currently successfully issuing as many as 50 changes per second with a flex5000 and hope to be able to achieve similar rates with the FCD. This is at TCA when the 70 cm birds are moving at over 3000 Hz/minute.

    Are there any data dropouts when changing frequency?


    Richard W5SXD anxiously awaiting my FCD 🙂

  30. Claudio says:

    Hi Howard

    will be nice to see online an impartial full test of your Fun dongle pro, with all the pro & cons , and a test on the ” road” live with different Sdr softwares..what do you think?



  31. Peter says:

    I need help I recieved my dongle yesterday plugged it in followed the instructions for setting up and testing but unfortunatly I can only get LBC ,I cant change the frequency.
    I am running in Windows 7 and using WR+.I have upgraded the firmware to the latest editionbut to no avail we are still getting LBC loud and clear.What am I doing wrong?
    Thank You
    Peter G7GCF

  32. Rob says:

    Pop over to the Funcube group
    Most issues are sorted very quickly. But check you are running the FCD front end, LO tuning can only be done via a DLL file with WRplus- also found on the group.
    Funny, I live In Bath, and listen to LBC via DAB most days. you will also find user guides.


  33. Ben Brockert says:

    Hi Howard,

    What is the antenna connector on the FCD? It also might be handy to add a small diagram showing the dimensions of the FCD


    • Rob says:

      Hi Ben the antenna connector is a SMA, good point on dimensions.
      I will take dimensions later this evening and report back, Unless some one replies first.


      • jimmie reeves says:

        The antenna connector on my new dongle in NOT a sma . pictures show two sizes. the new connector is a smb or smc . cant find deminsions of eather . but wont to get a connector thanks JIM

        • admin says:


          Which pictures are you referring to? I can absoultely categorically assure you that it is an SMA. I test every one three times using the same test jig and that has an SMA plug on it.


  34. Ari Thor says:

    Hello from Reykjavik Iceland
    What about get one Dongle to Iceland ?
    please let me know when I can order one

    • admin says:


      Check the Order your FUNcube Dongle Pro menu item. We have sold out again I am afraid, but there should be some more in a couple of weeks.


  35. Michael DL3YCW says:

    I am unhappy. Yesterday I’ve been listening to 144 575 MHz (or to a local radio-station).
    Today, the FCD is completely silent. I use it with a small rubber-antenna for a
    2m handheld radio.
    Neither WR nor Spectravue something to see or hear. The
    communication with the FCD works! Even a re-install the
    Firmware did not succeed. I tested the FCD to multiple PCs.

    Does anyone have any idea what I can do yet?

    73, Michael
    (with google-translation-helper)

    • admin says:

      Hello Michael

      I am unsure from your posting whether you are saying that the FCD was working fine but now doesn’t, or if it has never worked?

      Can you confirm that Spectravue is communicating with the correct soundcard (SoundCard In Setup)?


  36. Michael DL3YCW says:

    Hello Howard,

    until yesterday the FCD works fine. Today it shows no spectrum and no noise out of the loudspeaker.
    The communication with the FCHID006 and FCHIDBL works normally.

  37. Michael DL3YCW says:

    Hi Howard,

    please don’t ask me why. I don’t understand my problem. I tested on a Mac Book with parallels right now and it works!! The local radio-station and the packet-node on 144.800 MHz. All is ok. Tomorrow i will research the pc-problems.

    73, Michael

  38. F6HDW Jean Claude says:

    Hello Howard
    I received today the dongle #474. When I open Frontend FCHid3, I receive this error

    HIDOpen of Vid_04d8&Pid_fb56 returns 1
    Success, FCD found.
    HIDReadRegister returns 0
    Error, FCD read register.

    And when I set the frequency to 10000 an another error

    HIDOpen of Vid_04d8&Pid_fb56 returns 1
    Success, FCD found.
    HIDSetFreq of 99988 returns 0
    Error, FCD frequency NOT set.

    With the bootloader, I have

    HIDOpen of Vid_04d8&Pid_FB56 returns 1
    FCD found.
    Please wait: erase may take up to ten seconds…
    Erase completed.HIDOpen of Vid_04d8&Pid_FB56 returns 1
    FCD found.
    Error: device ID address NOT setHIDOpen of Vid_04d8&Pid_FB56 returns 1
    FCD found.
    Error: device ID address NOT set

    Any ideas for these problems ?
    Thank’s for your help
    F6HDW Jean Claude

    • admin says:

      Jean Claude

      I suspect that your FCD was in Bootloader mode. Can you install the latest 18f firmware, remove for ten seconds, reinsert, and try it please?


      • F6HDW Jean Claude says:

        With the help of F6BYJ my funcube working correctly now. Sorry to have bothered with this simple problem. You did a great tool for amateurs and I thank you for everything.
        F6HDW Jean Claude in ARIEGE France

        • admin says:

          Jean Claude

          No problem, I am delighted that you got it working.

          If you have any other questions let me know, even en français, parce que la YL est française et elle est une traductrice couramment (contrairement à moi).

          Merci, et bientôt, Howard

          • tony G3OVH says:

            Amazing Howard – you still have a YL – she must be very tolerant – or perhaps it not her kitchen turned into an SM rework lab 😉

  39. Andrea i3miq says:

    Hello howard I fcd nr. 316, I connected fcd
    with the soft
    vr plus and works
    responds to all commands but I can’t receive any signal
    with or without antenna is the same thing does not receive anything in any frequency it is perhaps a problem in input,
    can I send it to a control?
    What address should I send it and how many euros I must send to the
    return shipping?
    Thanks Andrea

    • admin says:

      Hello Andrea

      When you say it receives no signal, is there no noise?

      Can you check that the correct sound card is being selected by your software?


      • Andrea i3miq says:

        hello howard thanks for the reply
        FDC works correctly get the noise bandwidth regularly
        with FCHid active all connection parameters are regular and if I enter the frequency of 100 mhz as instructed and click default FCD receives see and feel the spectrum signal cw
        I also increased the input gain up to + 30 db but
        do not enter anything from no signal, without the antenna or the antennas connected to the same thing the noise does not change and do not receive anything,
        I also tried with the laptop in two meters near the fcd but nothing gets no signal
        hi I’m desperate

        • admin says:


          If you believe the unit to be faulty, you can mail it back to me and I will send a replacement. To speed things up, email me proof of posting and I will send you a replacement immediately before I receive your unit back.


          • Andrea i3miq says:

            Dear howard
            as you enter your e-mail receipt of delivery of the FDC

            RA 2989 2908 4 IT
            MoòeIo22R1-MOO OoIO\Q “‘,lJOO ‘ 8’I;\l&f1111~-SL[~

            Servizi Accessori Richiesti D Importo ContrassegnQ € (in cifre) (Contrassegnare con una Xl

            D Avviso di ricevimento (Mod. CN 071
            Fraz 7061
            causai . EE 02/ 3/2011 12. Peso gr.:63 Tariffe 7,00 frr.t 7,00 rv.A .•
            RA 2989 2908 4 IT

          • admin says:


            What was your serial number? I am trying to locate you on my system so I can mail you a new unit.


  40. Hi, I have no test-sets here; how does the FCD perform at 64.4550 MHz ? I would like to use it as a Pan-Adapter for an Icom Rig that has that first IF frequency.
    I have read elsewhere that near its bands edges – thus 64.4550- the FCD is not on top anymore. Howard, some indication on this? Thanks! 73 de Augusto hb9tza / i2jjr

    • admin says:


      I just tested a unit for 12dB SINAD.

      At 145MHz it was -123.8dBm.

      At 64MHz it was -118.8MHz.

      So it’s 5dB less sensitive at 64MHz. These were with the “Defaults” settings. I would guess that there’s sufficient gain prior to the IF stage such that this wouldn’t be an issue. If you like a bit of extreme soldering, you could always replace the HPF with a 1nF cap.


  41. Chris Lee says:

    Is the hard ware schematics open ? I havent seen them posted anywhere. What about the pic’s code ? is it released as well ? or only pre-compiled firmware. What about the API docs ? I see under ‘Downloads’ that its under construction, any eta by chance ?


    • admin says:

      Hello Chris

      There are a number of posts and comments already about the schematics and firmware. If you let me know what you want to be able to achieve I may be able to help you.

      There is a post on the programming interface here:

      I suggest that you also check the example source code to learn how to program the unit, there are a number of examples. It is a standard USB HID interface, so first you will need to understand about USB HID.

      The basic programming technique is to send a 64 byte HID command packet and receive a 64 byte HID response packet. The first byte of the command packet is the command itself, and command specific parameters follow. In response, the first byte is a success/fail followed by comand specific responses.


  42. Andrea i3miq says:

    Hi Howard
    the serial number of FDC # 316
    on behalf of Gaetano Molinari

  43. Michael says:

    Hi Howard.

    by a disease I could not not run my tests on.
    Tonight I have the FCD retested. He does not work properly.
    When I plug it into the PC the communication with the Frequency Control V2.0 is ok.
    All settings are correct in Spectravue.
    Perhaps from 10 trials is one or two times the chance to receive a signal. The receiving ends after a short time in a squeaking, about 500 Hertz. In the other time nothing happens and it is also nothing to hear .
    I would like to send the FCD for the analysis and repair. Please send me your address via email.
    73, Michael – DL3YCW

  44. Andrea i3miq says:

    Dear howard
    I forgot to give you my address for shipping FDC
    30121 VENICE ITALY

    FDC nr. 316 series you’ve shipped to Gaetano Molinari
    contrada piano diMaio Rende
    tks and 73 Andrea i3miq

  45. Rick KI6RLM says:

    Hi Howard. I’ve had my FCD a few days now, and have written some very rudimentary Mac OS X software that allows me to set the frequency and demodulate FM. I’m fairly confident in the frequency control, but the demodulation is not working at all.

    In numerous places you refer to “standard soundcard quadrature I/Q.” I don’t know what this is (I’ve never done this stuff before). I worked from the assumption that the left audio channel is I samples, and the right audio channel is Q samples, and wrote code to demodulate based on the information in this article:

    But all I get is unintelligible noise that saturates the output.

    Can you please verify for me how the data is provided in the audio stream? Thanks!

    • admin says:

      Hi Rick

      That is exactly what you get, I can’t remember which way round it is, but yes, I goes to one channel and Q to the other. Under the hood I provide standard USB audio at 96kHz sample rate, two channel, 16 bits/sample as per the USB spec (

      Typically you would also downconvert in software on the host: although in some circumstance you can use the zero IF and direct downconvert in hardware, bear in mind that as well as a DC offset (that you can calibrate out) there is also LO phase noise (that you can’t). By doing a second downconvert on the host with a software NCO and mixer from an arbitrary position either side of the hardware LO, you avoid the hardware limitations around the zero IF.

      I’ve had a lot of success with this on a Mac:


  46. Chris KB0TLW says:

    Hello Howard and everyone else!

    I just found out about the FCD tonight while browsing another site and I see I missed the March 4th sales batch. Dang it!!!

    Howard, when do you expect to have the next batch ready as I would really like to get my hands on one, and a friend I just spoke to about this would like one as well.

    Looking forward to your response.