There has been a lot of discussion recently about the need for a decent antenna in order to receive DTV. However, from time to time we make compromises in our personal lives that we’d never tolerate in our professional environments. Witness the following description of my own poor practice of engineering excellence:

I live in Chatsworth, roughly 28 miles line of site from the antenna farm on Mt. Wilson. I subscribe to Time Warner cable, but I don’t have easy access to put a cable drop in my kitchen. When we moved into this house a few years ago, I put a small color TV on the kitchen counter so that no one has to miss a moment of Desperate Housewives or The Bachelor. I won’t elaborate on that.

There’s no easy way to get an outside antenna to this TV, either. To get some sort of RF into the TV (and keep peace), I connected a short piece of RG-59 to the TV and added a 75 ohm/300 ohm transformer to the other end. I attached the spade lugs of the transformer to the #6 screws that hold the cover plate to the outlet box on a nearby lightswitch. This provided a tolerable, although somewhat snowy, picture with good sound on the upper VHF analog stations in LA. Lower VHF analog had barely watchable video, and adequate sound. War in the household was averted. Analog UHF was not strong enough to be discovered during the auto channel scan, but, thankfully, this wasn’t an issue to anybody.

This winter I finally gave in and faced the DTV conversion. I had a couple of the government coupons for DTV converter boxes, so I went to Best Buy on Feb 17, the original D-Day, and bought a $50 box. I didn’t do much research beforehand, I bought the more expensive of two boxes that I had seen advertised. This particular box was sold out at my local Target. I took that as a good recommendation.

I stuck the converter box in series between the existing coax and the TV. Now my antenna system consists of: Y-shaped 3” 300 ohm antenna, with both ends tied to the same piece of steel that connects to all the conduit in my house (which, or course, is tied to earth ground), then coupled to 75 ohm unbalanced....this goes through a 3 foot piece of RG-59 to the DTV box, which goes through another 3-foot piece of RG-59 to the 75 ohm input of the TV. I wasn’t expecting to get anything.

I should point out that my entire house is covered with stucco. If you’re not a building materials expert, stucco is a little like light concrete, smeared across a framework that resembles chicken wire. So the entire house is sort of a floating Faraday Shield. I honestly don’t know if the chicken wire ever sees ground, but it’s possible that an outdoor light fixture or two has an electrical box that is in contact with the mesh, so there’s probably a resistive path to ground in a few places. Also, the TV in question is on the west side of the house, and Mt. Wilson is to the east. No signal sneaking through windows unless it’s bouncing off a lot of stuff to the west of me. I’m not expecting anything at all.

I turn on the converter box and set the TV to channel 3. The box wakes up in Setup Menu mode. Time to fish out the AAA batteries and the remote so I can control the box. I tell it to scan for channels, and hey....it’s finding something!

The results astounded me. My notes reflect the pseudo channels that the box reported to me....I didn’t sit down and look up what UHF channels I was really seeing, and I think all of these are UHF. Here are the channels that give me solid picture in DTV; no freezing, no pixilated blocks in the middle of the screen:

2-1

4-1 4-2 4-3

5-1 5-2

7-1 7-2 7-3

9-1

28-1 28-2 28-3 28-4

30-1 30-2

44-1 44-3 44-4 44-6

54-1

56-1 56-2 56-3

58-1 58-2 58-3 58-4

Several other channels were found during the DTV scan, including channels 18, 30, 34 and 57, where the reception was marginal....video would freeze frequently, or pixilated blocks would hang on screen. Some of the subchannels on several stations, including the ones I list above, were silent, with solid black video. I don’t know if these subchannels were dormant at the time, or if there was a reception issue.

It’s also a bit ironic that the stations that gave me the best analog reception, 11 and 13, did not provide sufficient signal to be decoded in DTV. Perhaps the performance will change when analog really goes away, and the final antenna/frequency schemes are put into place.