Need help getting started with ATV

[VK3OHM]

Thought I might play around with ATV. Have good access to VK3RTV here in Victoria, and it's seems reasonably cheap to get on air. Would like some suggestions.

1. I'll need a 70/23cm Yagi. I have no real interest in hand crafting one, unless it's in kit form - not real interested in metal work. Where can I buy one?
2. Receiver - all I need is a commercial set top box, that allows for manual tuning to 446.5MHZ?
3. TX - Might be fun to build a Mini-Kit (although the SMD components are a concern). Is the EME23TX-ATV what I need? Which audio sub-carrier do I need, 5.5,6.0 or 6.5 MHz ?

[VK2GFR]

Marc,
My first 23cm ATV Wide-band Tune-able Rx was a kit & although it was a little challenging, very rewarding to say "I built that".
As for antennas, a loop-yagi is the way to go, however an 8 over 8 is also a goer ( H plane antenna).
As we do not have any Digital ATV Repeaters in Sydney, the STB's in the cheapies I've come across do not allow for anything below 500Mhz.
Mind you if there is a way around the pre-set tuned circuits & hacking the pre-programmed band plan, then it's open season on pre-fab STB's.
Good luck with your project.

[ADMIN]

Admin note: this topic moved into the (relatively new) ATV sub-forum

[VK2XSO]

You should be able to fine a "cable ready" VCR which is able to tune to 444MHz on it's tuning display.
There are also plenty of analog flat sceen TV's which also tune to 444MHz.

Then there are still plenty of old VCR's and turret TV's floating around. You can tune their UHF right to the bottom and they usually tune below 444MHz.
The old Beta Toshiba's used to be renoun for tuning down to 426MHz without modification.

For 444MHz receive, go with Low Noise Pre-amp. As low as you can go. A Gladesville GaAsFET pre-amp will easily give you a good 0.6dBNF.
If you're not up to building one, then you can buy a store bought masthead preamp. But do not settle for anything more than 1dBNF. Most pre-amps are wide band and crapola. Some as high as 3dBNF.
You'll have to search heard to find one lower than 1dBNF, so sometimes it's easier to build it yourself.

Antennas, most 70cm yagi's aren't much good for ATV, they have lousy frequency response across the band from 420-450MHz. Good for 432-434MHz and not bad for 438MHz, but often too narrow for ATV.
There may be some home made antennas out there that are ok. Commercial antennas like an RFI stainless steel yagi are wide enough for the task.
The high gain bow tie, (cross) yagi that places like DSE sell are ok. The '99' element antennas were suitable but expensive.
You can't go past the store bought phased array antennnas. These used to be $49, but now I noticed Jaycar selling them lately for $149. >:(
Go down to Bunnings, buy some coat hangers and some chicken wire and 1 inch PCV pipe and make your own for $5. Copy the design from the catalog, or print the elements on some PCB.

An 8 over 8 is also suitable, though I tend to think they're a little wide on the beamwidth. They're perfect antennas for repeaters, and a reasonable compromise for home use.

For 23cm TX, It's hard to go past the minikits kits. The 23cm transmit antenna. I've used dishes, loop yagis and yagis.
In that order, dishes are the easiest to construct from surplus, and yagi's the hardest to build.
Dishes are harder to mount up high, while yagis are very easy.

Height is might. I used to use a 1.5m dish at roof height. It worked for a long time, but when I replaced it with a 32 element yagi 10 metres above the roof, it kicked a***.
Loop yagis are easier to construct and much more tolerant that yagis.
Quagis are also fairly tolerant in their construction and can be made using stacked PCB's.

There's lots of little tricks you'll learn along the way. Receiving a picture from a repeater is the biggest challenge.