Project:

A home video transmitting system via remote control from work.

Designer(s):

N8UDK

Description:

I'm typing this message to you on my computer here at work. The program I'm using covers about 1/2 the screen. I have another window covering 1/4 of my screen. This window has the output of my ATV repeater in it. The repeater is six miles away. The audio is coming through my SoundBlaster card speakers. I pickup my HT, type a few touch tones and now am looking at the output of one of the cameras at the repeater site. I spin the camera around (via a pan/tilt rotor) and see my building where I work. It's neat but here's where it gets real interesting...

With the press of a few more touch tones on my HT I have just keyed up my ATV transmitter at home 12 miles away. Oops my boss came by so I shrank the ATV window down so he didn't see that I'm playing around. (The loop yagi on my monitor has him guessing though!) At home I just turned on the living room camera. (I have red lights through-out the house so my wife knows when the ATV repeater is on.) I am looking at my four month-old baby bouncing in her bouncy-chair. I can hear her giggle. My wife just waved. Keep in mind I receiving the output of the ATV repeater via 1.2 GHz. A few more touch tones and I'm looking in the backyard. I have a camera on my tower that looks straight down. My dog (named Doppler) is barking. I can hear him. I pickup my HT and through a speaker mounted on my tower tell him to stop. He doesn't but it was a good idea anyway. I now switch to my other camera on the tower at home. This one is on a rotor. I pan the camera until I see my neighbors KC8CCG's house. Across the street is Brinston Park. Nothing much happening there. I now flip to my computer's video output in the basement. My Davis weather meter that's attached to the computer shows it is 31 degrees outside and the wind is 8 MPH from the south west. I should mention all the sources from home are overlaid with my callsign in the bottom left. (I want to stay legal).

Here is a real world ATV application using my home remote control system. I ordered a 1.2 GHz VSB filter from DCI. My wife, baby, dog, and I went to Ohio to visit the in-laws over Christmas. The filter was coming via UPS and was going to be left on the doorstep. This is not good. It just so happens that I have a camera outside that shows the front door and porch area. My friend N8QPJ each day turned on my home ATV transmitter from his basement 10 miles away, switch to the front door camera, and checked if the package had arrived before having to drive to pick it up.

Some Technical Information:

The remote control video/audio/id switcher in figure 1.0 is the heart of the system. I allows me to switch to one of eight audio/video source inputs by pressing the red buttons on the top of the box. There are also jacks on the back for controlling external devices like the tower rotor, ATV transmitter, and tower speaker. Inside is a Basic II Stamp which checks for button presses and activates the proper relay to pass the video and audio to the RCA output jacks which connect to the ATV transmitter. An Intuitive Circuits DTMF decoder board (DTMF-8) accepts commands via a 23cm frequency and emulates me pressing the buttons on the box. The onboard computer (the Basic Stamp II) doesn't know if I pressed a button on top of the box or it was done twelve miles away via touch tones. Also installed is a GVID board to overlay my callsign with the selected video source.

Hardware:

• PC Electronics TC70-10 ATV Transceiver
• M2 420-50-11 11 element 440 antenna
• Several color indoor cameras from Sycard
• Three outdoor "Ball" cameras from ATV research
• Parallax BS2-IC Basic Stamp II
• Intuitive Circuits DTMF-8 DTMF decoder
• RMD Technology GVID overlay board
• Eight 4PST relays and eight momentary push buttons
• Down East Microwave 1.2 GHz 14 element loop yagi
• Down East Microwave 23LNA preamp
• PC Electronics TVCX-23 crystal downconverter
• Diamond Stealth64 2001TV video card

Hardware Sources:

• P.C. Electronics (626) 447-4565
• M2 (209) 432-8873
• ATV Research (800) 392-3922
• Parallax (888) 512-1024
• Intuitive Circuits (248) 524-1918
• RMD Technology (734) 482-2670
• Down East Microwave (908) 996-3702
• Diamond Multimedia (408) 325-7000

Conclusion:

This project took quite a bit of effort but I really enjoyed working on it. Interestingly I'm still discovering the benefits. When were away from home I can have someone watch my house inside and out. They can tell me if the furnace is broken and the house is freezing. I can know if there is water on the basement floor or a smoke detector is going off. From work I can watch NASA shuttle missions by remotely turning on my home transmitter and selecting that video/audio source. It's a great tool when I'm at the repeater site since I can have an ATV transmitted source when no one else is around for testing. And the most rewarding benefits from this project came from seeing my baby roll over on her stomach for the first time, her sitting up, and even her first attempt to eat solid food (it wasn't pretty). The ability to see all these events that I wouldn't normally be able to is what makes ATV all worth it to me.

- Chris Oesterling N8UDK

Fig 1.0 - QTH remote control video/audio/id switcher

Fig 2.0 - QTH tower with two cameras, 2.4 GHz, 440 MHz, 1.2 GHz ATV antennas, and outdoor speaker

Fig 3.0 - My office computer with ATV receive capability (see my front door?)