[mythtv-users] OT: OTA HD

[Brian Wood]

On Thursday 25 December 2008 11:48:14 Daniel Kristjansson wrote:

> No, not really. Or, at least not without spending thousands of
> dollars on filters and remodulators. You can't combine the signals
> with a simple Y filter because then you will then be broadcasting
> the cable signal over-the-air. Cable companies are under strict
> FCC rules to make every effort to catch and disable any such
> leakage transmissions because they interfere with broadcast
> licensees use of the spectrum. That is if you do it all your
> neighbors stop getting OTA reception which tends to upset both
> them and your local broadcasters.

The real potential problem is that cable systems utilize frequencies that in 
the real outside world are used for aeronautical navigation.

Back in the day, we installed a new Ampex ADO-2000. Some genius of an engineer 
had chosen 40.5 Mhz. as the clock frequency. The third harmonic is 121.5 
Mhz., which just hapens to be the international distress frequency. We 
discovered this when a few very unfriendly types in Air Force uniforms showed 
up at our door a day after we put this unit into service. Square-wave clocks 
make a lot of third-order harmonics.

Turned out it was actually a Russian satellte that had first detected the 
radiation from the ADO, and they reported the fact to the USAF, which really 
hates to look silly.

The fact that we were about midway between Newark International and 
Teterborough airports didn't help the situation much either.

>
> If you have power and ethernet in the attic you can place a network
> based ATSC device such as a HDHomeRun next to the antenna. Even if
> you just have power there you can set up power-line networking to
> reach the device.

I agree this would be the best solution, for several reasons.

Having the HDHR set up for PoE would be a good deal as well.
-- 
beww
beww at beww.org