Video Camera Detector Schematic?

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Chris Foley
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Re: Video Camera Detector Schematic?

Post by Chris Foley »

BTW, gadgeteer, what is the link to that Electronics Circuit Schematics page? Thanks, and sorry for getting off the subject!
gadgeteer
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Re: Video Camera Detector Schematic?

Post by gadgeteer »

Chris --- click here. (I was gonna just post the URL 'cause it was short, but after my other post I just KNEW someone would call me on it...) ;) <p>And it only has a bit over a thousand schematics, I think. Some genius actually offered to SELL this url on ebay for 20 bucks last month (he said it took him MONTHS to find it); I simply searched on some of the items he had listed, and found it inside two minutes. Ebay cancelled his auction (no I didn't tell; anybody dumb enough to bid is fine with me)...<p>I once emailed someone who had bid $30 on a CMG Ifinity Task Light --- I told him at that time he could buy it from Lifestyle Fascinations for $20, free shipping; he ignored my email and bought it for $30 (plus shipping) anyway. Can't figure some people...<p>I imagine the video scrambler works rather well, GeeW. Stuff that's transmitted on an RF channel is pretty easy to disturb. Though, video is amplitude modulated, so the stronger the jammer the more complete the obscuring (just think in terms of how a distant TV station is still watchable even with 90-95% snow...)<p>If you send a series of squarewaves, I bet you can totally blow the horizontal sync...<p>For what it's worth, I just bought a VCD-42; if you all insist I can easily be talked into opening it (after I receive it) and maybe reverse-engineering it a little. This unit does not detect RF but the actual 15,750 hz video scan signal...
geewiz
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Re: Video Camera Detector Schematic?

Post by geewiz »

gadgeteer, give us an appraisal of the unit before you go and violate dmca :) . Curious as to effective range and operation.<p>BTW, you have a site, don't you? Do sales? I think I may have bought or visited a site run by a namesake.
gadgeteer
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Re: Video Camera Detector Schematic?

Post by gadgeteer »

OK pardon my denseness, what is "dcma"??? (I'll probably feel SILLIER after you ANSWER...)<p>No I don't have a website; and not in sales. I had applied for a job selling components; as far as I know I HAD the job, but she never called back. And I never called HER back (maybe it was a TEST). Truth is I was DREADING working under quotas, and calling people and hounding them to buy stuff... NO OFFENSE to those in sales --- I just prefer to design and build stuff that works. All MY designs work the FIRST time. (If you BELIEVE that I have some excellent beachfront property to sell you...)<p>I'm expecting the range to be very short. Think in terms of antenna being ‚\ = C/f (even using ¼-wavelength), you can see that the emitted signal won't amount to much. Which is why I probably won't be able to add a gain stage --- the "s/n ratio" probably won't let me...
geewiz
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Re: Video Camera Detector Schematic?

Post by geewiz »

Here's an anti-dmca site that explains it<p>http://anti-dmca.org/faq.html.<p>Reverse engineering a product/device has been interpreted as a violation of this law.
Matt
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Re: Video Camera Detector Schematic?

Post by Matt »

Other than in your own home and in bathrooms, what would be the problem with hidden cameras? If you don't do anything wrong, then there is no reason for the gov't to watch you. Somethimes these cameras can HELP you. What happens if you get mugged and nobody is around, other than a hidden camera and you have the jammer on. Now there is nothing that can help you find the mugger. I agree about the cell phone jammers. The should be turned on in public places, if there is an emergency then there are landline phones to use.
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--Matt--
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gadgeteer
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Re: Video Camera Detector Schematic?

Post by gadgeteer »

"The right of the people to be secure in their persons, papers houses and effects against unreasonable search and seizure shall not be violated; nor warrant issue, but upon probable cause, supported by oath or affidavit, and particularly describing the places to be searched and the items to be seized." Ever read words like that? (The PROBLEM is that the COURTS have REDEFINED terms like "probable cause" and "unreasonable"...)<p>Then too, in American law, is the concept of "Innocent until PROVEN guilty". I should not have my privacy violated unless I have given probable cause to deserve surveilance. I do not want cameras recording when I think I am alone and scratch myself, or pick my nose; I do not want to trust my freedom to "face-recognition-software". I do not want my personal information placed into databases that can be accessed either by hackers or by those with the funds to BUY it. My private life, my funds (such as they are), my credit rating, my sexual preference (I am STRAIGHT and unmarried but do not believe in promiscuity, btw), my demographics, NONE OF THAT is ANYONE'S BUSINESS!<p>Contrast the words of BIll Clinton, national TV soon after the Oklahoma City Bombing: "We may have to give up a few of our freedoms in the interest of public safety..."<p>...with Benjamin Franklin, who said: "Those who are willing to forsake freedoms for safety deserve NEITHER FREEDOMS NOR SAFETY!!!<p>I do not want to be observed while I work; my job performance evaluation should be based on --- my performance. If I DO the work, and DO IT WELL, that should be the basis of my performance reviews. Being single, I lack the "built-in-gofer" to buy my car parts or pay bills; I must use the work phone to chase parts. I've been told that it "looks like I am non-productive" (by one worthless supervisor; every OTHER one gave me EXCELLENT reviews!); I do not want to be on camera all the time.<p>If I check into a hotel I do not want to prepare for bed wondering if I have an audience; likewise trying on clothes at a store. Simply, I value privacy...<p>[ May 06, 2003: Message edited by: gadgeteer ]</p>
geewiz
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Re: Video Camera Detector Schematic?

Post by geewiz »

gadgeteer, could not have said it better.
chessman
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Re: Video Camera Detector Schematic?

Post by chessman »

I'm curious in what it's like if you reverse engineer it....
gadgeteer
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Re: Video Camera Detector Schematic?

Post by gadgeteer »

I received the VCD-42 today. As with most of what I own, the screws came out within the first couple of minutes. I found --- a simple ferrite bar, length about 4 inches, with a single coil around it. Hot-glued to the board. Looks like the inductor is paralleled with a poly-styrene capacitor --- unmarked. Anybody have an RLC meter they would sell me for cheap? Board was very small, has one transistor amp, and an LM324 quad op-amp. Nothing seems to have been "anti-inspection-treated" (numbers ground off,potted, etc). This unit very much has the look of a "garage-industry-product". But it seems to WORK. <p>Turn on a TV anywhere near it, and the unit is SWAMPED with the horizontal frequency. Haven't tried a camera yet, suspect it will work well. But NOT in the same room with a TV!<p>What if I replace the 4-inch ferrite bar with an 8-inch one, winding a coil of the SAME INDUCTANCE around one end? Won't I significantly increase its sensitivity?<p>I intend to re-do the case for this; it uses the battery-compartment Pac-Tec style, but it's TWO INCHES THICK; then has a standard KNOB on TOP of that. I want something that will fit in a SHIRT POCKET. This has lots of wasted space --- large rubber doorknob-bumper and large block of sponge as the "PCB mounting", lots of vacant space. I think a standard pocket AM-radio volume-wheel (built-in-power) would be ideal...<p>If anybody has an RLC meter, priced for a "laid-off-but-looking" colleague, I shall be most appreciative...
Bernius1
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Re: Video Camera Detector Schematic?

Post by Bernius1 »

gadgeteer, i'd've thought you'd just make your own from scratch. i think ECG & R-Shk sell video chips w/built-in osc's. output that to a TO-3 trans,& you should be running. but for pwr consumption, i'd imagine a square wave, PWM'd to a short duty cycle would maintain range & effect with less net current over time. is there such a thing as 'coil saturation', a point beyond which an inductor cannot store a proportionate field for the current input ?? you can vary duty cycle at a fixed distance, and find least cycle for most effect, no??
Can't we end all posts with a comical quip?
gadgeteer
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Re: Video Camera Detector Schematic?

Post by gadgeteer »

No-vice, you seem to be talking about an ACTIVE device --- as in "jammer". The VCD-42 is PASSIVE; it's merely a receiver. The point is that this will inform you of any electronic device nearby that contains a 15,750 oscillator; 'cause such a device will be some kind of VIDEO circuit. By "sweeping" a room, one can determine if there are cameras operating, where and how many. <p>I have an RF detector, bought at a garage sale for $5 from someone who didn't know what they were selling. The RF detector will reveal audio and video TRANSMITTERS (which are WIRELESS and transmit their signal over the AIRWAVES), the VCD42 reveals WIRED cameras that transmit their signal over COAXIAL CABLE.<p>A jammer might be fun, but passive detector is sufficient for me; as long as I know where the cameras are, I can feel more "private"...<p>So what about a bigger ferrite rod? Won't that increase the sensitivity of the receiver??? Or do you all think the VCD-43 simply has a SECOND COIL attached to an anenna (like your average AM receiver)?
Bernius1
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Re: Video Camera Detector Schematic?

Post by Bernius1 »

AHHHH. Passive. Well,that was my $.02 . Maybe the larger rod, or what about an IF signal? Beating the 15,750hz against a harmonic may boost sensitivity (like biasing a photo-trans.)
Can't we end all posts with a comical quip?
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