Santa Barbara Amateur Radio Club
ATV Past News and Information

SBARC Amateur Television
By Rod Fritz, wb9kmo@sbarc.org

Our next ATV SIG meeting is July 8th, but will begin at 8:30am at the Elk's Lodge, not the Red Cross Building. We'll look for ATV equipment lurking in the goodies at the SBARC Bazaar.

At the June ATV SIG meeting, Ellis Pilgrim AD6J installed SSTV on the Club Station Icom IC-730 HF rig. Until we install a computer-actuated PTT circuit, push the Icom transmit button before you send the picture.

Joe Huemphreus K6DXW, helped route the coax for the Club Station's ATV receive station. We need to put a connector on the cable and it's all set to go.

I tuned up a 10-watt 434 MHz ATV transmitter that Marvin Johnston KE6HTS gave me. It will be installed at the Club Station soon. Does anyone have a video camera to donate?

The Tuesday ATV Net is very active. In the last month, we discussed model rocketry, television history, antenna ordinances and installation, school demos, APRS, high-resolution SSTV, ARES van SSTV, Field Day ATV, computer issues and San Luis Obispo ATV. We also sent lots of interesting SSTV pictures that I hope you saw. Welcome to new ATV SIG members KL0IC, K6LES and KF6HHY.

This month, Bruce Gordon N6OLT sent our first high-resolution (P3 mode) SSTV transmission. He also found that Scotty-S1 was notably better than Robot-36 for VHF operation.

On Field Day, we amassed an impressive ATV demonstration (and added 100 points to the score). James Gardner KF6HHY took SBARC ATV to new heights as he made our first Hang Glider ATV transmission. James carried a battery-powered 100 milliwatt 2441.5 MHz ATV transmitter and helmet-mounted camera as he launched from the Elings Park hilltop. Viewers watched in amazement on a 2441.5 MHz ATV receiver in the ARES van and in the VHF operating tent. Field Day video was also transmitted on 2441.5 MHz and 434 MHz from battery-operated equipment on top of the van and on a tripod that was moved around the site. Visitors commented that they didn't know that amateur radio operators could transmit television, too!

Special thanks to Jim Allen KF6HHX for the beautiful Field Day ATV images and the fine "Rube Goldberg" 434 MHz antenna connector.

For our first ATV mobile operation, I drove from Goleta with a 1 watt 434 MHz transmitter in my car, up the mountain to the WB9KMO ATV Repeater and back down to Elings Park. Paul Sheffield W6VLM, Bruce Wilson KF6RAI and Dick Johnson W6DNN and a few others watched the dizzying ride at the Field Day site.

Paul and Bruce saw snow-free pictures from the WB9KMO ATV Repeater using Paul's 1277.25 MHz receive converter and Bruce's home-built loop yagi antenna, and later, with Paul's home-built quagi antenna. Congratulations on creating beautiful pieces of equipment that worked as well as they looked.

73's for now. I look forward to seeing you on the air soon (or at the Elk's Lodge, not Red Cross, on July 8th).

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March 10, 2000 - WA6SVT ATV Downconverter

ATV SIG Members and Friends,

I now have detailed info for the 1277.25 MHZ ATV Downconverter project (files are 350KB each for schematic, parts list and layout, available on request). The design looks very good to me. A few details need to be worked out, like where can we get the GaAsFET (or equiv) in quantities of less than 100!

The estimated cost, including case and connectors is still around $50. We'll know more when we order our first set of parts and build a prototype.

I have four circuit boards in stock and two are already reserved (N6OLT and WB9KMO). If you're committed to building the project now and want to reserve a board, the first two requests get them for FREE! (reply to this email). These free boards were donated by the Amateur Television Network (ATN). More boards will be available in the future for $6, possibly less.

We'll discuss the downconverter and antenna designs at the "Second Saturday" ATV SIG meeting tomorrow (Saturday, March 11th) at the Red Cross building (2707 State St. in Santa Barbara) from 10am to noon. I'm taking my Extra Class exam earlier in the morning and could be a little late. Walt Haake will be there to let you in. Please make yourself at home and I'll be there as quickly as I can. Check out the club station, it's a class act. If you're bored (I doubt you will be, there's usually a lot of activity), make a few contacts on the rigs there.

73's, Rod WB9KMO

P.S. Remember, "Hams should be seen as well as heard!"

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March 5, 2000 - First "Second Saturday" Meeting, March 11, 2000

SBARC ATV SIG Members,

We've had a great turnout for the Tuesday night ATV Net with lots of lively discussion. We need a few more of you receiving the 1277 MHz video. It's not difficult or expensive, and help is available.

This week, I discovered that excellent video is available in the Mesa Lane area on the ocean side of the Mesa in Santa Barbara. This is very encouraging, because we thought the Mesa might block the signal. Hopefully, at least two of you will be receiving ATV in that area very soon.

Next Saturday, March 11 from 10am to noon, the ATV SIG will hold its first "Second Saturday" meeting at the Red Cross building, SBARC club station. The address is 2707 State Street in Santa Barbara (parking lot in back). Earn ATVSIG "Gold Stars" by building your equipment and helping others build theirs. This week will be an important planning session. Figure out what you want to do and what you need to do it.

Mike Peddicord is going to install a 1277 MHz antenna and downconverter at the club station so we have an ATV receive station there for everyone to use (He earns 10 Gold Stars). We're also going to talk about construction projects, specifically, how you can get your own receive setup going. Antenna and downconverter construction will be the hot topics. If you're available, stop in to participate.

I have a downconverter in mind and already have a few circuit boards for it, donated by the Amateur Television Network (ATN). If you want one reserved for you, let me know - reply to this e-mail. I ought to have the parts list and cost (probably about $50) in time for the meeting. The downconverter converts from 1277 to 174-216 MHz (TV channels 7-13), is tunable, and uses an MRF966 Gasfet (or equivalent), TUF-5 mixer and an MAR6 for the output. A crystal controlled downconverter is available, but it's more expensive. If you have an other ideas, your input is valuable.

Here are a few antennas that we're considering for our antenna construction project(s). We expect that they can be built for almost no cost.

• One is a 1296 MHz quagi. There are actually 10, 15 and 25-element versions. We may scale it for 1277 MHz, but that might not be necessary (see attached ZIP file).
• Another is called a "hog fench" antenna, which is a parabolic reflector (made of, you guessed it, hog fence wire) with an extended dipole feed (see attached GIF file).
• We'd also like to consider a dish design if we can find a small (2' to 3'), economical dish to use with an easily fabricated feed. Some small dishes I've seen use a dipole with a small reflector as the feed. Do you know of any inexpensive dish sources? The feeds are usually easy to modify or replace.

Some of the topics we'll discuss about antennas are:

• How well will they perform from 1276-1282 MHz? What will be gained by scaling the quagi from 1296 to 1277 MHz?
• How easy do you think they'd be to construct and to tune?
• Which one would work best for you? Would you be comfortable helping others build one?
• Do you have ideas for improvements or for a better antenna design?

Keep in mind that many of us may also want a 2441.5 MHz (or 434 MHz) transmit antenna (all are vertically polarized). We want to antenna-mount the 1277 preamp or converter and a 2441.5 1-watt amp or 100mw transmitter, too. There are lots of possible combinations, including separate antennas or a dish with a dual (or triple) feed. Fortunately, the antennas are small. WA3RMX has some sort of 3-band circuit board feed that I've heard of, but I haven't located info about yet. A 434/1277/2441.5 MHz feed would be ideal. Each band needs to be fed separately since we like to transmit and receive at the same time.

Next month, Saturday April 8 from 9am to noon, we'll do some serious (and fun) construction. Of course, you're welcome to construct your project before that meeting. If you do, we can check it out at the meeting and tweak it up for you.

There's a lot happening in Santa Barbara on ATV. Come and be an active part of it!

73s, Rod

P.S. Don't forget to check out the Amateur TV page on the SBARC website at www.sbarc.org. It has all the info for the Tuesday night ATV Net and I'll be adding more info soon. The website links to the Amateur Television Network website, too, which has links to ATV websites all over the world!

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Contact

If you have any questions or comments regarding the ATV SIG or the ATV NET, send an email to Rod Fritz at wb9kmo@sbarc.org.