Get Bitten by the ATV Bug!
With the advent of Digital TV, we now have the capability of sending and receiving broadcast quality video streaming.
Getting started in ATV can be as simple as hooking up a suitable preamp to your cable-ready television set and hooking up to your TV aerial (if you didn’t trade it in for one of those silly little dishes…) Although not optimum, this path is often the first step taken by many budding ATVers. It turns out that our AM repeater output of 421.25 MHz falls on cable channel 57 (not to be confused with UHF broadcast channel 57). Unfortunately, many of today’s television sets designed for cable TV reception lack the sensitive front end to make this the best choice for on-air reception of AM ATV signals. However, if you have line-of-sight to the repeater and live within about 10 miles or so, then this will probably work fine. Another popular method is the set-top converter box, which does nothing more than down-convert the 421.25 MHz signal to either channel 3 or 4, depending on availability/interference in your area.
The next thing you’ll need to contemplate is your station antenna. Keep in mind that the W8BI ATV repeater sends and receives all video signals using horizontal polarization. This orientation helps us keep interference from other hams and band users to a minimum. So don’t expect to see a great signal using your 440 FM rig’s 5/8th wave vertical unless you live within a mile or so of Beyers Road. On the other hand, a small 10-15 foot yagi antenna cut for 421.25 and elevated to about 20-30 feet should do fine, as long as you don’t have any major obstructions between you and the repeater. Our repeater tower tops out at 165 feet and is located at aproximately 1000 ft MSL, so signal coverage is fairly good to the greater Dayton area and surrounding suburbs. For a look at some predicted gain patterns of our dual slot antenna used on 421.25, click here. There are relatively few manufacturers of ATV gear, but gear is available.
For Digital ATV, continue to read the articles on this web site. To give you a glimpse of how our Digital ATV works, continue to read the following.
23CM FM ATV Repeater Information
The 23cm receiver and transmitter at the repeater site allows for a 23CM/70cm crossband link, both forward and reverse. In other words, if you transmit a 1280 MHz FM video signal to the repeater, it will crossband repeat into both the analog AM (A5) and Digital DVB-T (D2) 70cm transmitter links at the site, so you or others can see the incoming 23cm FM video on the outgoing 70cm outputs. Alternately, any 70cm DVB-T signal (QPSK @ 2 Mhz bandwidth, video PID 641, and audio PID 642) that the site receives will be outputted into the 1258 FM ATV transmitter at the site, allowing you or others to see the 70cm A5 and 70cm D2 on the 1258 FM ATV output. Note that the 23cm FM ATV repeater at the site does not have an in-band repeat function on 23cm. In-band repeating only occurs on the A5 and D2 70cm links.