Bryan awarded his certificate and ribbon

Next step? District Science Fair

Hanalani says that Bryan can now enter his science fair project into the District Science Fair if he wants to. We think he should do it, just for the experience of it. He's not so sure and it means more work. He has to submit a 5 page literature review if he wants to participate. He is intimidated by that, so we are researching it to understand what it is better.

What do you think? Should he take his display to the District?

Placed in the top 5 of 48!

The winners were announced last night at Parent's Night at Hanalani Schools and Bryan placed in the top 5 of 48 entries in his age group! His ribbon says Honorable Mention. This is the second year in a row that Bryan has placed in the top 5! Congratulation's Bryan!

Done!

Bryan will turn in his science fair project on Amateur Television tomorrow.

Building the Display Board

Results Graphs

More Photos

The Final Test

Today we did a lot of testing. We got to borrow two yagi antennas from Hank (kh6hak) and Chuck(nh7xl). We found a stretch of road along the way to Haleiwa that goes a mile, so we tested there. We set up a transmitting station at N 21º 33.862 W 158º 04.423. The manual we looked at said that with 2 yagi directional antennas we should be able to have a good signal for 8 miles. So I got all set up and we started to test. The first test was at point blank range, the signal quality for that test was video:10 audio:10. Then my dad drove away 1\10 of a mile, and the quality there was video:6, audio:9. Then he drove to 3\10 of a mile , and the signal quality there was video:3, audio:7. Then my dad tried to recalibrate the receiver. Afterwards,we could only receive video. So we did another round of testing.

The first test was at point blank range and the video quality was 10. Then we went to 150 feet, and the video quality was 8. Then we tested at 350 feet away, and the video quality there was a 7. Then we went to 375 feet apart and the quality there was 6. Then we went to 440 feet and the signal quality was 3. After that its was uncopyable.

I think we had difficulty because of our very low power, and cheap receiver.

Fixing minor problems

Yesterday I cut out holes for the batteries so they don't rattle. I also drilled a hole for the antenna connecter to come out of.

Testing

Yesterday we did some testing. We discovered that it has to be line of sight to get a clear signal. We also discovered that everything in the box rattles and makes a lot of noise, so I'm going have to fix it today. Also the camera rotates so i have to secure that to.

More Photos

Arrow Antenna

Today Dad brought home a Yagi directional antenna from Hank (kh6hak) which I get to borrow. A Yagi antenna is a directional beam antenna. There are three parts to a Yagi antenna, the reflector, radiator, and directors. The more directional parts there are on the antenna the more powerful it is in that direction, but less powerful in any other direction. This antenna will hopefully maximize my range for my project.

Putting It All Together

Today a lot was done. First we got a plastic container for a project box. Then we determined all the items we needed and went back and gathered all of the stuff needed (foam,a metal strip,lock,slip conectors,screws, nuts,bolts,spliter,wire,and wire connectors). First we measured and cut the piece of foam, and placed it in the project box. With the foam in the box it cushions all the components. Then we made our own dipole antenna out of some wire and spare plastic. We used a formula out of my ham radio tech manual to determine how long it should be. Then we added handles and a lock.

Next we worked on the power switch that will run the camera and the transmitter. We got it wired in for just the transmitter for now, but we are trying to figure out how to attach 2 batteries so they run both transmitter and camera from one power source.

Portable TV arrived yesterday

Picked up this TV which HAS A CABLE TUNER at Overstock.com for $32. Shipping hurt though. It can be powered by 12 volts, has an external antenna port and a nice 7" screen. It comes will all the cables and connectors we need too. This will be the center piece of the receiver.

Some photos of this weekend's successful test

I was very excited to start seeing components arriving in the mail. We got the transmitter first, then a couple of mini-cams. Saturday we started using alligator clips to attach the camera/transmitter/antennas/TV/batteries/switches together just to see our first ATV signal on screen. Somehow it worked! We got a signal on TV without any direct connection. Now that we know it works, I need to start to assemble the components into a small, neatly organized device with hopefully a single power supply and a single power switch. A handheld ATV station! Then we can start testing range.

(Click on a photo to enlarge it.)

Transmitter and testing

This week the transmitter came in the mail. We now have all the materials needed to start testing. We also tested the UHF frequency from our house to hanalani schools. It works pretty well, but it disorted the T.V. signal to any T.V.s on the channel 59 (which is the same and the ham radio 434.000) near by. Next we are planning to put together and test the transmitter this weekend. If it works we would have had our first ATV transmit on the air.

Transmitter delayed

Message from Videolynx:

Sorry for the delay. The Z70A's are just going through the last bits of assembly. Should have it in the mail on Monday the 13th or sooner.

Ravi KA3NNJ
Videolynx

Measuring the distance

Today my dad and I measured the distance between Hanalani and our house. It ended up being 0.96 miles apart. Our transmission will have to cover this distance.


Hanalani
N21º 26.478
W158º 00.580

Home
N21º 26.667
W158º 01.458

Getting some materials

Today my Dad ordered a transmitter so that we can test it when it comes in. It is a Video-lynx Z70A 70cm Mini Video/Audio transmitter. It is the miniature transmitter that I am planning to use. The entire manual can be found here.

Doing Some More Research

Today I read an introduction to ATV from Amateur Television Quarterly. I learned that it can be fun and fairly inexpensive. I also learned all the things you can do with it.