Thread: Ambitious Video Security System

http://www.cnn.com/WORLD/africa/9812...e.thrower.car/

I had a feeling that was coming!

My parts are finally starting to roll in. I received the wireless video sender today and tested it out. I will probably need to augment the antenna on these, but the form factor was what interested me. The transmitter has a plug on the back to plug in the IR dongle with two eyes (perfect...quad and DVR!)

It runs on 9V@200mA. Didn't say in the listing, but they had always been 12V before. Oh well, I can work with it. I cracked it open to be sure it would work with the mods I need to do. There is a simple mod to increase the power in these which I will probably do. Also, it looks like the IR sender portion is a standard 433MHz serial RF link module, which means I could send digital data over it just as easily as the IR. The antenna connected to module can be removed and placed on a more powerful external antenna (may need to add a coil to it to match the impedence of the original.) I will need as much power as I can legally obtain since it will be located under my hood. Not the best place for wireless signals.

I will post some pics of it and describe the mods I need to do hopefully tomorrow or over the weekend (as soon as I can get to it.) I am hoping to get the DVR by this weekend as that is the part requiring the most mods. I am anxious to crack into that. Unfortunately, the only source I could find for that was located in Hong Kong, so I am not necessarily expecting speedy shipment. I have since located some US Sources for a similar version, but quite a bit more than I paid for it.

Also, I bought a mini piezo siren that will be installed in the vents and a pack of 5 personal alarms claiming 130dB+ output for up to one hour. I have not bought the strobe light or additional cameras yet (waiting to see the quality on the one I bought.)

The last thing I will be doing is choosing the enclosure to put everything in. Obviously I am going to need to know the size of everything. It will need to be waterproof, though. I am keeping my eye on options right now.

Scott

Got the wide angle IR camera today. It is a CMOS imager with a 2.8mm lens. I tested out if the angle will be wide enough and think it will work perfectly. Looks like mounting it in my dash will cover both the driver's and passenger side. If I mount it high enough, I should be able to get a clear view of the back seats as well.

It is a bit bigger than I had hoped for (diameter) but should still work in this application. The imager has fairly fast light compensation, so if I quickly "bloom" it, it recovers pretty quickly. Overall, I am happy with it for $50. Images are clear and recognizable. Not camcorder quality, but it is a CMOS, I didn't expect that.

I also received the 2 mini piezos and boy are they loud AND annoying! It is uncomfortable to listen to in my workshop, which is quite big. And that is only one at a time. With both in the small space of the car, I can't imagine anyone being able to withstand it (unless they brought earplugs.)

I'll probably do the mods to the wireless video sender this weekend. Still not enough to start piecing everything together yet.


Tonight I am going to spend time repairing a 7" LCD screen I picked up dirt cheap (looks like the previous owner wired the power up backwards.)

More later.

Scott

Got the LCD screen working (sorta.) A trace was blown from the +12V entrance to the polarity protection diode. Nice diode, it shorted right out instead of blowing. Well, actually that was a good thing because it protected everything else. The ribbon cable to the front controls was ripped. I rigged something up quickly, but only a couple of the buttons are working. Will have to check over my work again.

Also looked at the 2.4Ghz video sender a little more. It has a 5V regulator in it that looks like it is powering everything off from. This means that I shouldn't have any troubles running it off 12V-16V. The 7805 has a max input of 35V. It will run hotter with the higher voltage and waste more current. I might put a couple of 1A diodes in series with it to drop the voltage a bit. It should regulate down to 6.5V.

Looks like I shouldn't have any problems attaching an external antenna. Also, tapping off straight serial data from the IR port looks simple enough (haven't decided to do that, yet.) I was hoping to find a micro in there to let me switch between more than 4 channels, but it looks like the channels are hardwired to a 4 position switch. Oh well, I can interface that to my micro anyway. I will take some pictures tomorrow to explain all the mods.

Status:

I promised pictures and I did take them, but it is a PITA to post them to this forum. So, unless somebody asks me, I will be creating a webpage with all the pictures once this project is completed.

I started out by removing the pathetic 2.4 GHz antenna and modified the PCB to accept a coax, which is routed out to a panel mount SMA connector with a whip antenna (from an old wifi router.)

I found the pi network I needed to modify in the video Xmitter module to increase xmit range. Oddly, the pads had nothing present (should've been a 680 Ohm resistor) I jumped them with a piece of copper.

I removed the switch and installed 8" of wire in its place to turn power on/off with my controller.

I removed the DC power jack and connected 8" red/black wires for power

The channel selector switch just grounds one of 4 inputs to choose the channel. I can tap into them easily by removing the 0 ohm resistors (jumpers) going to the switch. Not sure if I want to bother with this or not. One justification is that it will not be easy to change once in the car. Allowing external control of *everything* will make my life easier in the long run.

I haven't removed the audio/video jacks yet as I am waiting for the rest of the stuff to get a better idea how I want to connect everything. I may just use the RCA cables and solder them in place.

I still need to add a better antenna for the 433Mhz IR section, but I haven't decided what I am going to do with that yet.

All connections were strain-reliefed with shrink tubing and high-temp hot glue. I will ziptie mount them as well once it is in the enclosure.

Thinking more about it, the main PCB inside the video Xmitter is nothing more than a carrier for the two modules. Other than the 5V regulator, there isn't much to it. The modules can easily be removed and placed on a different board. I am thinking I may decide to do that, and place them on my controller board. I will make this decision when I am further along.

One nice advantage to that is that I can control the form factor and size of the full assembly, this way. I don't need to find a way to arrange this odd shaped board.

I have decided that I am going to remove the video transmitter module and IR module from the video transmitter. I have also decided that a quad is probably much overkill. The most likely used feature will just be one camera at a time. I can get some easy-to-use video switcher ICs with built-in amps and build this into my controller board as well. Then I just switch the power to each camera along with the video.

I picked up two amplified microphones. I will use one for the interior of the car and one on the exterior. This will use the stereo channels on the DVR and wireless video. All that needs to be switched is the video. I "may" change my mind about the quad after I finally get it, but right now I am pretty much set on including the switcher in the controller board. I just can't see me needing the quad view and this essentially puts everything except the DVR on one board. While I would love to claim that I could build a HDD DVR myself (not PC based), I am not that good... yet! I do know my limitations.

My ultimate goal is to attempt to fit everything into a 5.25" external CDROM enclosure and put the DVR portion in a removeable HD rack. I will then need to find a place to hide it in the interior of my car since this will NOT be waterproof (I seem to recall a pocket in my inside rear quarter panel for some OEM gear not included in my car.) Of course, I would prefer to put it in the engine compartment, so that is still an option done differently.

Oh well, I have been (slowly) putting together a video security system for my home. The quad will work nicely for that.

I also picked up a xenon strobe light, and finally purchased the i455 boost mobile phone and serial cable. This is for internet in the car, but with the serial connection I "could" also integrate it into my controller if the modem is hayes compatible (more than likely.) Not 100% sure why I would want to do that, so we'll have to wait and see. Not real high on my priority list, obviously.

can't wait to see this...

we're definitely gonna need a video