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Products => Thermal Imaging => Topic started by: Mias on March 09, 2019, 02:04:19 pm

Title: Introduction
Post by: Mias on March 09, 2019, 02:04:19 pm
Hi Everyone
I thought I would just drop a post and thank Fraser for advising me on the forum
I have A Flir PM575 and a Flir E30 hacked.

I use it for TSCM purposes to help me locate parasitic devices hidden in ceilings and walls







Title: Re: Introduction
Post by: Ultrapurple on March 09, 2019, 04:46:45 pm
Quote from: Mias on March 09, 2019, 02:04:19 pm
... to help me locate parasitic devices ...

I presume you're using 'parasitic' in the wider sense of 'something unwanted' rather than describing a type of passive device (Great Seal etc)?

It sounds like a fascinating job and I'd love to see some pictures - but I guess so would the people installing said devices. Good to know you're on the case, and welcome to the forum.
Title: Re: Introduction
Post by: eKretz on March 09, 2019, 10:05:46 pm
Interesting application. Does it find the devices every time?
Title: Re: Introduction
Post by: Hydron on March 10, 2019, 08:10:25 pm
I guess even something like the Great Seal might give a telltale pattern as the room heats/cools due to the cavity required to mount it.
Title: Re: Introduction
Post by: helius on March 10, 2019, 08:22:52 pm
How does the selectivity compare with a NLJD (https://en.wikipedia.org/wiki/Nonlinear_junction_detector)?
Title: Re: Introduction
Post by: eKretz on March 10, 2019, 10:27:03 pm
Yeah but they've got that masking stuff in the news now that is supposed to work pretty good. Somebody expecting a SCM search might be able to disguise it pretty well. Not to mention the ability to just lay down a complete layer of insulation across/under the whole outer surface. A mic only needs a pinhole, done right I bet it would be tough to detect via thermal.
Title: Re: Introduction
Post by: Ultrapurple on March 11, 2019, 08:53:18 am
Quote from: eKretz on March 10, 2019, 10:27:03 pm
Yeah but they've got that masking stuff in the news now that is supposed to work pretty good.

Can you provide a reference to this? I'm interested (in a general sense).

If something is generating heat then that heat has to go somewhere, though a few milliwatts inside a brick would be pretty hard to spot.

By way of comparison, the internal walls in my house are one brick thick and even a central heating radiator blasting a couple of kW on the other side isn't as bright as you might expect.

I have no doubt that Mias is able to see some, er, 'unexpected' items, not least because there often isn't time to hide something quite as well as you'd like. But I imagine a well-concealed 'thing', particularly one near a heat and power source (LED lamps, anyone?) would be a right pain.

I'm pretty sure TSCM counter measures relies far more on the Mk 1 human brain and experience than any of the electronic aids, thermal or otherwise.
Title: Re: Introduction
Post by: eKretz on March 11, 2019, 10:21:07 pm
I've read about a few in the last 6 months but this is one of them:

https://newatlas.com/thermal-camouflage-material/55229/

I'd also imagine a decent section of something like Aerogel would be extremely difficult to see low levels of heat through once it's soaked to room temperature.
Title: Re: Introduction
Post by: isecus88 on October 09, 2023, 11:22:00 am
Thermal Camera can only be used to locate electronic items powered on. If it is powed off, there is no heat, then thermal camera can not find it.
NLJD can be used to locate any electronics no matter it is powed on or off. The working technology is quite different. NLJD is also called harmonic radar. It emits a fundamental wave signal, receives the 2nd, 3rd or even higher harmonic/combined wave echo signals re-radiated from the target, and detects them. It is a Radar system for target judgment, identification and detection.

When it comes to cost, there is big gap. :-DD

I think less than 1K USD, you could get a very good thermal camera with high ir resolution, from those top brands.
While, an entry level NLJD equipment, just for B2C cost, should be over 5K USD. Advanced NLJD would be over 10K USD.
Because of the high cost, you would see only high-end organizations would use NLJD, such as government, police, military would use NLJD, or some service companies who offer security services to those rich people.
Title: Re: Introduction
Post by: nikitasius on October 09, 2023, 07:38:57 pm
But you can build it yourself. No need 5k$ for.
You need to emit shortly and strong and listen the echo (and don't burn the receiver 😁).
Title: Re: Introduction
Post by: isecus88 on October 10, 2023, 02:29:28 am
 :-DD How fast you could make it?
If you send stronger signal, I mean the power sumption would be big and it would be harmful to health?
Besides, if you just listen to the echo, may be not easier to differentiate the result between semi-conductor and metail-junction.

So for fun and test, DIY what you said is OK. For real application, not workable at all lol :scared:
Title: Re: Introduction
Post by: nikitasius on October 10, 2023, 06:38:07 am
I need to pickup my notes. My friend (who do warfare stuff also) gave me good advices.
If my memory aren't fails, you're sending a pulse 10W-15W for a lenght 1ns-10ns and listen the echo upto 1ms.
While you're sending it you need to short your receiver input to avoid it be burned.
So the main algo is: short - send - open - listen - process - repeat