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User restrictions?

I'm seeing a lot of folks using my KiwiSDR to listen to local MW stations - all of which stream their content elsewhere on the Internet. I wish I could prevent users from listening to blocks of frequencies as they ignore my "owner info" & "status" texts of "DO NOT USE to listen to local MW! ???????????!". The only other solution I see that might work is a HPF to block everything below 1.8 Mc - though I'm not sure if the stopband attenuation will be enough as I'm just a few km away both sites (one line-of-sight & the other spitting distance through an adjacent block of flats) - but will certainly bugger any other MW & below reception, which I'd prefer not to do. Suggestions, anyone?

73, Brett/p.


  • I have discovered that I have the same issue. The only solution that I see available on the Admin page/Control tab is to set the Inactivity time limit to something like an hour or, in my case, two hours.

    I know that this doesn't answer your central question about setting up a block, of course. It is an excellent question and one that I'm also interested in hearing possible solutions for.
  • NooElec has a MW band reject filter for $8.95
  • Raised a similar problem back in 2017

    "I have a particular problem in that a lot of Dutch music pirates use my SDR all day long to monitor their own transmissions around 6MHz.

    What I really need to be able to do is to be able lock out certain frequency ranges or restrict the amount of time individual users can stay on the SDR before getting automatically kicked off. I currently have the inactivity time out set at 15mins but I may have to reduce this still further."


    And also in 2018

    "I have a few KiWi users who sit on the same frequencies for a lot of the time, usually listening to broadcast stations that can often be heard by listening to streamed audio on the web.

    Would it be possible to add a 'blocking' function to a DX tab ? This would prevent folks tuning to frequencies marked by the center frequency and bandwidth described within the tag and could also offer an Admin defined URL that could be used to point KiWi users to an online streamed audio service."

    There is also a problem of legality in some countries, where allowing the remote use of a receiver by others, to monitor some signals or ranges of frequencies could be problematic.


    Martin - G8JNJ
  • I'd like to second, or third, this request.
  • Has anyone else had a user in St. Petersburg, Russia hanging out for long periods of time and re-logging in immediately when kicked off? I can't figure out any good reason that the Global Comms frequency of the USAF should be listened to for hours by someone there.
    I also put a per-user time limit on but I don't like penalizing legitimate amateur use, which I don't mind even if it's extended periods if it truly is being used.
    Glenn n6gn
  • joking...

    Create tiny website with a code your valid users can translate into this week's access password by some simple formula.

    code like "0241950430" password = TheRye
    or "9780099549482" = ToMockingbird
  • edited January 2019
    I use DD-WRT routers and if I want to block an Internet user I'd setup a rule in IP tables like this:

    First I'd get the user IP address from the user.log on the KiwiSDR:
    ssh to the KiwiSDR then run this command:
    root@kiwisdr:~# cat /var/log/user.log |grep Bourbon
    Jan 20 00:20:12 kiwisdr kiwid: 3d:21:48:30.613 01.. 1 670.00 kHz am z0 "" Bourbon, Illinois, USA (ARRIVED)


    Then make a firewall rule in the DD-WRT router to block that particular IP access to the LAN behind the router NAT.
    iptables -I FORWARD -j DROP

    Of course if the troubled user comes in from another IP address, you are left to add more addresses or range of addresses such as "". Use the actual IP address and not the xxx stuff.
  • As WA2ZKD mentioned, the Nooelec AM bandstop can be helpful and is reasonably priced. The level of attenuation is modest so I run two in series for more effect. The main benefit is lowering strong AM signals in the -20/-30 dB range down to -40/-50 dB which reduces AGC overload and cleans up the spectrum more generally.
  • Thanks for all the suggestions.

    I'm already ratcheting down user access time (not good as requires me to do & then undo). With one of the MW transmitter sites ~3.5 km away, I suspect making it inaudible will be a bit of a challenge. And I've seen these folks change IP addresses.

    The problem is that they keep tuning to local MW that's already streamed on the 'net. Unless I can restrict what they can tune to, then it will continue to happen.

    73, Brett.
  • After knocking it down, you could jam it locally, just within the receiver. A PIC or Arduino and a single SiLabs synthesizer can do it easily and cheaply. You can probably get 3 channels in case there are some other 'favorites'.
  • ".. you could jam it locally .."

    You mean like this? [Kiwi in Seoul listening to AM BCB station jammed by the DPRK. Similarly with stations on 819 and 855 kHz]

    I find this whole discussion somewhat unsettling.
  • Although I was thinking of doing only at the receiver's input, I agree that the whole issue and the need for it is a bit disheartening.
    It sounds like they are using the same modulation pattern on multiple carriers. That would tend to imply that the source is at a single location, which if over the air and actually transmitted, can require a lot of ERP to be effective against path loss.
    Maybe just notch all of MW, that's a little less distasteful to my way of thinking.
  • Global timeout except Ham (or other selectable) bands, that would allow all users full access but push the focus onto the owner's prefered use.
    Or If the radio server has more than one Kiwi have the second in eight channel, audio only, mode and redirect some frequency bands to that.
    I do understand why some users want to make some type of use less attractive, I've previously run single-user fairly high bandwidth SDR's on the web only to see the sole user forget they are connected so leave the thing tied up till timeout.
  • > I don't like penalizing legitimate amateur use, which I don't mind even if it's extended periods if it truly is being used.

    > Global timeout except Ham (or other selectable) bands

    Do you guys seriously see tuning inside of ham bands as more legitimate than tuning outside of them? This thread is indeed quite unsettling.
  • For me it isn't about where they tune, I certainly don't see ham bands as being special that way. But I do object to 24 hour 'use' of a channel and automatic re-login on after the 'user' is kicked off. It appears to be a machine rather than a human. I don't know why a machine located in Russia needs to monitor a military communications channel on my KiwiSDR continuously to the exclusion of other human users. If a human user is interested in actually *listening* anywhere I have coverage, I don't object.
  • edited January 2019
    I don't specifically and actually tried to ensure things like CB worked well enough to be useful but I do think it is a legitimate conversation to have. I had an Irish pirate (assumed) use one frequency much of the day, didn't bother me as I didn't get a full radio very often and I tried to improve reception there too as it was a good marginal case to work on.
    Resources and channels are finite, why not try make the designed use work better than the non? If someone sets up an antenna for 0-5MHz but deaf at HF end why would it make sense to have a user tied up a channel where reception is poor?
  • edited January 2019
    I don't own a KiwiSDR but I really feel the same frustration as you guys. I know how sometimes I struggle to get a slot on the one KiwiSDR that gets a good reception of the signal I'm trying to catch, so when I see in the user list slots taken for hours for stuff that I personally find pointless, I get a bit upset too. Sometimes I check and it's just static on that frequency in the middle of nowhere, sometimes I'm pretty sure that they're not even listening, that they're away from the computer but left the KiwiSDR open!

    It's sure that some uses are a waste, like it was mentioned, commercial broadcasts also available on the web; unless you're checking radio propagation or something, but then you wouldn't keep it open continuously for extended amounts of time. But I don't think we should see restricting this as the only solution, that's pretty negative. Education works too. I know that maybe you don't want to go through such extremes, but maybe adding the web radio URL on the station tag would help steer people that way, who knows?

    And again, as for the USAF HFGCS, or other channels, military or other, that operate on a fixed frequency round the clock, my approach for that is that if it's popular, someone should make an audio stream of it relayed on the web. That way, providing for bandwidth, any number of user can connect and listen to it at the same time, and only one receiver slot for everyone is ever tied down for it. So it's true that listening to HFGCS that way is not the best. However, that military network is indeed popular to some, because it carries strategic command messages (for example see And people listen to it for hours because it's active all day and they're interested in monitoring all these messages.

    And the fact that it would be automated, 24/7 and a machine, not even a human, doesn't mean it's a waste. It's actually smart, if they're recording. That way they can go back on the recording and spot on a spectrum view if and when there were any message, and recover them. Sometimes, for stations that are unpredictable and could transmit at any time within a span of hours, or maybe not at all, setting up these automated recordings is unfortunately the only practical way to monitor them, because there's no way to know. It might seem pointless but you'd be surprised at what random people try to achieve and how it actually does make sense.

    Correct me if I'm wrong, but I get the impression that you guys get angered by particular individuals. That strikes me, because the internet is big, and I don't think it's very healthy to focus on policing individual users. The internet is full of trolls and idiots and you just got to let it slide and ignore them, otherwise I don't think it's healthy; not because of the impact of starting a "war" with them, but because of the impact on yourself trying to control that.

    And at the same time, I know you paid for it and it's yours, but I don't see the point of encouraging KiwiSDR owners to feel like God (or a judge, or Santa if you want) and give good points and bad points to users based on what use they make of the receiving slots offered to them. I know that policing to ensure fairness between users is necessary, but in what I see here there is also some policing of what users choose to listen to. Nobody forces you to share your KiwiSDR with the public, and thank you all for doing so, but if you share it it's for a reason; so that users can enjoy the service, and they're still the best judges of how they would enjoy it best. So I think it's healthy to let them appreciate that; and I know it does try my patience too sometimes, but it's a good thing. And frankly when I see KiwiSDRs with several slots taken by WSPR autorun sessions, I don't understand that either ;)

    I appreciate how using frequency filters could be a solution, however I feel that jamming crosses a line that shocks me. I can't condone that, come on, jamming is bad?? From a technical and administration point of view, blocking is what is done against disruptive and malevolent users. Fortunately that doesn't seem to be much of a problem on the KiwiSDR network. And blocking is rarely used as a fairness tool, because there are proper and better tools to manage resource fairness. The listening time accounting and daily quota by user look like good features to me. What is your experience with that?
  • Most of my motivation to limit user time on the KiwiSDR's came from the users themselves. Hams mostly, that "need" to monitor the nets that local noise prevents them from hearing well. So I made timeouts and passed out passwords, and tried to accommodate those that made the requests. Added more KiwiSDR receivers to facilitate the demand. Then I determined that many people have antennas that transmit well but don't hear well for various reasons. So started recommending receiving loops and selling them. That actually works for some. I noticed some of the "preferred users were sitting on dead air for long periods too. So I have removed all restrictions and it is Fiesta Sharing now. I don't even hold a slot for myself. But then I have the old RSP 1 and a decent ORION II that I can listen to, right? Or if in a bind, the kick option. But generally the receivers are vacant most of the time when I use them anyway. I've never blocked anyone's IP other than to see if it would work, and that was only a test. The quality of KiwiSDR antennas is improving and therefore, there are many very good KiwiSDR's available now. At least that is my experience.
  • Recently, I have had several users "camp out" on local AM frequencies during the football season, effectively occupying all four slots for hours at a time. One of them even had multiple tabs open, taking up two slots at once. So I set time-out limits and then contacted those amateur radio operators whom I know are frequent users and gave them an override password. That is about the best solution that I can come up with for the moment. But it would be nice to have some sort of option in the control panel to assist with this.
  • edited January 2019
    perhaps something that sets a specific time limit for a frequency range ? maybe JS driven ?
    there could be say 3 entry fields, each field can input a defined lower frequency, defined upper frequency and a defined time.
    when a user connects and tunes within the defined frequencies, the timer countdown begins.
    how and whether the user should be notified about this is another discussion since there are a multitude of optional methods presently possible to inform a connected user about a time limit within a defined range of frequencies.
  • The situation seems to have improved after I further ratcheted down the 24-hour user time limit to something that clearly annoys those doing more worthwhile things than listening to local MW - and left it that way. I will reduce it further after having a chance to look through the logs to see how much that could be without limiting TDoA access. A few ruin it for everyone...

    73, VR2BG.
  • I've mentioned this before but it bears repeating. This problem can be partially solved by having more public Kiwis. If you have a Kiwi and have thought "Look at that Kiwi map. There are lots of existing public Kiwis. I'm not going to bother making mine public." that's the wrong perspective, IMHO. Lots of those Kiwis have marginal reception. Sometimes despite great effort of the operator to overcome the problems.

    Only a small percentage of the Kiwis sold are currently public. Worse, a lot of the Kiwis that used to be public have disappeared (sadly, even some really good ones)
  • Indeed - and I'm not helping matters much by running six WSPR receivers on what is now the only Kiwi QRV in this neck of the woods.

    The next mental health toy acquisition here will likely be a Red Pitaya, which will free up my Kiwi & other SDRs.

    Moved everything into a different room of the flat here yesterday & can get the GPS antenna into a location where it sees a bit more sky, so hopefully that's helping folks doing TDoA.

    73, VR2BG.
  • you might want to consider setting up AI6VN's kiwiwspr scheme for your 6 channels, you surely spot more stations with no other changes
  • There's a RPi here waiting for me to have some spare time & since it turns out not to have enough grunt to be a server for one of my other SDRs, I think it's destined to hang off the Kiwi to chew on WSPR or FT8.

    73, VR2BG.
  • I think an RPI might do very well for that purpose. To my recollection, Rob has been using one with up to 20 separate receiver processes on WSPR that way. I'm not sure how it will do on a busy band with FT8, the number of spots/15 seconds can be pretty staggering - I see 30-40 every cycle sometimes - but it would definitely be interesting to try it.

  • Any way to block either a particular frequency or user by IP? All week, someone has been tying up a receiver, nearly all the time near as I can tell (from periodically checking), tuned into a MARS frequency. It effectively reduces my KiwiSDR to just 3 channels. And there's not even anything there when I go to listen :)
  • I ended up using an iptables entry in my router to block the offending IP address.
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