hi
which part of the OSCOR 5000 full kit can work for this solution?
David Rom
GD Intelligence Security LTD.
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On Sun, Oct 24, 2010 at 7:01 PM, James M. Atkinson <jm..._at_tscm.com> wrote:
The loop antenna that you describe will help a little, but as the frequencies get lower and lower the geometry of the antenna starts getting cumbersome, things start getting larger, and is you use a sideband antenna is is very easy to saturate the entire band that you are trying to filter, the specific frequency you are seeking is not finely dialed in, and it can be tricky to use for this.
Yes, the loop and bandpass filter will work, and I have used them in the past like this. But I got vastly better results when I wound a single bar antenna of a very specific frequency, and tunes it so that essentially it was a huge filter itself. Then I ran it into a small concentrator ring inside the frequency specific antenna, and then outside of the antenna passed the signal into a BPF attached to a ultra-low noise pre-amplifier.
cptkaos wrote:How effective would a bandpass filter (say 32.0 KHz - 32.9 KHz) be when used with a loop antenna with the range of 20 Hz to 50 KHz? On Oct 18, 2:51 pm, "James M. Atkinson" <..._at_tscm.com> wrote:The optimal electronic way is to use a magnetic antenna, in the form of a small loop of ferrite core with a very sharp bandpass filter at 32.768 kHz. A good rule is that if you can "hear" the timing crystal on a digital from 2 feet away you should be able to "hear" any magnetic radiation coming off a digital recorder. A very sophisticated digital recorder that presents miniscule amounts of RF energy will often provide a considerable magnetic signal if you know what to watch for. The spy is going to deal with a very large and very heavy enclosure to keep this leakage down, but since most spies obsess on keeping their devices small they compromise the detection of magnetic signals. I have some very nice stick antenna's that I have made that are resonant right at 32.768 kHz, and they are easy enough to build and impedance match to a 50 ohm filter, and then to a 50 ohm pre-amp, but get the preamp well away from the antenna and use double shielded cables for everything. It does involve thousands of loops of wire, some careful use of capacitors, a ferrite loop, and a piston cap to settle it right on frequency. -jma David Rom wrote:Hi TSCM expertswhat is the best way to fins digital recorders in while we sweep a room?David RomGD Intelligence Security LTD.On Sat, Oct 2, 2010 at 5:54 PM, <soca..._at_aol.com <mailto:soca..._at_aol.com>> wrote:Bug Hunting with Anritsu's Spectrum Master�http://www.youtube.com/watch?v=jGv3nNSIsfo-- You received this message because you are subscribed to the Granite Island Group "TSCM-L Professionals List" group which is the oldest, and the largest TSCM group on Earth. To post to this group, send E-Mail to TSCM-..._at_googlegroups.com <mailto:TSCM-..._at_googlegroups.com>, to contact the list owner and moderator please send an E-Mail message to j..._at_tscm.com <mailto:j..._at_tscm.com>.This group is sponsored by Granite Island Group http://www.tscm.com/to improve the profession of hunting spies, and to educate others in the craft of technical counter-intelligence. Granite Island Group performs bug sweeps like it's a full contact sport; we take no prisoners, we don't play fair, and we give no quarter. Our professional goal is to simply, and completely stop the spy.Granite Island Group Offers World Class, Professional, Ethical, and Competent Bug Sweeps, and Wiretap Detection using Sophisticated Laboratory Grade Test Equipment.-- You received this message because you are subscribed to the Granite Island Group "TSCM-L Professionals List" group which is the oldest, and the largest TSCM group on Earth. To post to this group, send E-Mail to TSCM-..._at_googlegroups.com, to contact the list owner and moderator please send an E-Mail message to j..._at_tscm.com.This group is sponsored by Granite Island Grouphttp://www.tscm.com/ to improve the profession of hunting spies, and to educate others in the craft of technical counter-intelligence. Granite Island Group performs bug sweeps like it's a full contact sport; we take no prisoners, we don't play fair, and we give no quarter. Our professional goal is to simply, and completely stop the spy.Granite Island Group Offers World Class, Professional, Ethical, and Competent Bug Sweeps, and Wiretap Detection using Sophisticated Laboratory Grade Test Equipment.-- James M. Atkinson President and Sr. Engineer Granite Island Group jm..._at_tscm.comhttp://www.tscm.com/- Hide quoted text - - Show quoted text -
-- James M. Atkinson President and Sr. Engineer Granite Island Group jm..._at_tscm.com http://www.tscm.com/
-- James M. Atkinson President and Sr. Engineer Granite Island Group jm..._at_tscm.com http://www.tscm.com/Received on Sat Mar 02 2024 - 00:57:24 CST
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