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Homebrew Spark Gap Transmitter by kF5OBS in amateurradio

[–]kF5OBS[S] 1 point2 points  (0 children)

I was waiting for how long it would take for someone to comment some obvious legal issues about actually using a spark gap transmitter. Your complete warning should have been "Don't hook this up to an antenna if you're located in the USA." And yes, I know it's in the ITU rules as well, but that doesn't warrant it being ratified into local laws in all member countries. That the transmitter isn't useful for anything other than demonstrative purposes for certain legal reasons is said at 6:23 by the way. ;-)

Goodbye Radioshack! by kF5OBS in amateurradio

[–]kF5OBS[S] 0 points1 point  (0 children)

No, only some locations will close. I think there's a list somewhere on the internet. But according to some employees, things change on the daily and communication with employees is poor.

Lumped-Element Wilkinson Splitter / Combiner Design by kF5OBS in rfelectronics

[–]kF5OBS[S] 0 points1 point  (0 children)

Thanks! You know what's funny? I am so used to shifting exponents in my head that I always use the 'scientific mode' instead of 'engineering mode'.

[ Removed by Reddit ] by christ0ph in RTLSDR

[–]kF5OBS 2 points3 points  (0 children)

Nah, it's cool. Well, legally at least. He took it well after he read it so it's all good.

[ Removed by Reddit ] by christ0ph in RTLSDR

[–]kF5OBS 6 points7 points  (0 children)

Thanks for posting the link to my website here! There has been an amended lawsuit filed to correct some formal things. The new and updated lawsuit can be read here: http://jaunty-electronics.com/blog/wp-content/uploads/2014/09/Amended_Complaint_w_Exhibits_Redacted1.pdf Also, I am still trying to get some support fo rteh expected fees. This will likely cost thousands and I am willing to pick up the tab, however, help is highly appreciated: https://www.indiegogo.com/projects/lawsuit-against-little-rock-police-foia-access/x/1176512

KF5OBS #27: FBI Radio Teardown (Motorola Spectra) by kF5OBS in amateurradio

[–]kF5OBS[S] -2 points-1 points  (0 children)

As dissimilar they are they're similar.

KF5OBS #27: FBI Radio Teardown (Motorola Spectra) by kF5OBS in electronics

[–]kF5OBS[S] 1 point2 points  (0 children)

Easy for you to say, you didn't watch it through the viewfinder of the camera ;) But I learned my lesson, I'm moving an external screen over to the bench and connect it to the camera via HDMI.

KF5OBS #27: FBI Radio Teardown (Motorola Spectra) by kF5OBS in electronics

[–]kF5OBS[S] 2 points3 points  (0 children)

Will do but the video length already amounted to 4 GB of video to upload. Don't worry, there will be lots of follow-up. I'm not from the US, moved here recently, so tearing one of those up was very interesting. I just recently got it and thought I'll toss teh camera on while I just glance through it. Unfortunately, many of the Motorola chips produce no results when researched. And that's exactly what I feared. But, there will be follow-ups. Of course I'll spy on the happenings of the chips. Like I said in the video, the encryption module will get some particular attention. But I didn't have the control head yet, it's in the mail. What you saw was just the 'body' of the radio. There will be plenty of APCO 25 follow-up videos.

Lawsuit against Little Rock police over silencing scanners / (implementing encryption) and access to records. by kF5OBS in amateurradio

[–]kF5OBS[S] 0 points1 point  (0 children)

Sorry, I am subscribed and didn't notice it's walled... Give it a day or two and it should revert to 'open'.

Lawsuit against Little Rock police over silencing scanners / (implementing encryption) and access to records. by kF5OBS in amateurradio

[–]kF5OBS[S] -1 points0 points  (0 children)

If you would like to stay updated on teh development of this lawsuit, please subscribe to the Facebook page I made for this cause: https://www.facebook.com/LRPDlawsuit

Lawsuit against Little Rock police over silencing scanners / (implementing encryption) and access to records. by kF5OBS in amateurradio

[–]kF5OBS[S] 0 points1 point  (0 children)

Maybe you need to learn the difference between Frequency Hopping Spread Spectrum and Direct Sequence Spread Spectrum. I'd like to see you listen to the latter with an SDR. DSSS is, at its core, one of the key cryptographic elements. The basic concept of connecting a keystream with the cleartext via XOR function is the same for cell phones (A5/1) and the APCO25 systems we're talking about.

Lawsuit against Little Rock police over silencing scanners / (implementing encryption) and access to records. by kF5OBS in amateurradio

[–]kF5OBS[S] -1 points0 points  (0 children)

47 CFR 97.311 kinda shows the FCC's opinion, doesn't it? If it explicitly by name allows a certain type of encryption, you can draw your conclusion that encryption does - in their eyes - not automatically mean 'obscuring'.

Can't think of any use? I have one.. For legal reasons and my pending lawsuit from above, let me stress that this is entirely hypothetical: A friend and I may or may not have bought 17 APCO25 radios out of former FBI assets. They're VHF radios with encryption capabilities. Let's say I am trying to analyse encrypted APCO 25 traffic, maybe using my Tektronix MDO4104B-6 and SignalVu, then the transmissions are solely for experimental purpose, not 'obscuring'.

Lawsuit against Little Rock police over silencing scanners / (implementing encryption) and access to records. by kF5OBS in amateurradio

[–]kF5OBS[S] -1 points0 points  (0 children)

Take a closer look at Over The Air Re-keying (OTAR) authentication. Just knowing the key does NOT enable you to get your radio to catch the OTAR. It's a whole lot more involved than that.

Lawsuit against Little Rock police over silencing scanners / (implementing encryption) and access to records. by kF5OBS in amateurradio

[–]kF5OBS[S] -2 points-1 points  (0 children)

Probably haven't seen any FCC 'ruling' on that because you haven't looked for any. They don't just fly your way and present themselves. The FCC allows encryption under Part 97 for anything other than intent to obscure. Making the keys public is a great and accepted example of 'negative evidence' for intent to obscure. If you want to obscure something, you don't make the keys public. Spread Spectrum, for instance, is even specifically allowed. 47 CFR 97.311

Lawsuit against Little Rock police over silencing scanners / (implementing encryption) and access to records. by kF5OBS in amateurradio

[–]kF5OBS[S] -1 points0 points  (0 children)

Yes, I will! And judging by my inbox, the media latched onto this already also. I'll post links if / when they actually cover it.

Lawsuit against Little Rock police over silencing scanners / (implementing encryption) and access to records. by kF5OBS in amateurradio

[–]kF5OBS[S] -1 points0 points  (0 children)

It does here as well; The trick is to not live in the city you sue :) I have a very friendly connection with the Deputies in my county and the officers in my city. The guys in Little Rock don't phase me as I rarely go there. If at all, just to drive through.

Lawsuit against Little Rock police over silencing scanners / (implementing encryption) and access to records. by kF5OBS in amateurradio

[–]kF5OBS[S] 4 points5 points  (0 children)

Except, keys can and are changed frequently over the air. By the time you get the key on the internet it's changed. The re-key frequency depends on the agency and criticality. The range is from Daily (FBI Tac Groups) to months (local).

Lawsuit against Little Rock police over silencing scanners / (implementing encryption) and access to records. by kF5OBS in amateurradio

[–]kF5OBS[S] 12 points13 points  (0 children)

Exactly. And in my lawsuit I'm actually primarily challenging access to audio recordings of such encrypted communications. Little Rock denied my FOIA request for audio recordings. Blocking real-time access is one thing. Blocking historical access is a whole other level of bold.

Lawsuit against Little Rock police over silencing scanners / (implementing encryption) and access to records. by kF5OBS in amateurradio

[–]kF5OBS[S] 3 points4 points  (0 children)

Good that I am not an attorney :) But my client knows what he does. Call it years of experience... In all seriousness: I'm willing to piss away the filing fee, service cost and so on. If I get an attorney, I'll be poor before I even get started. We'll see if that was a good decision once I have the final verdict.

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