Brian's Brain

The latest in a series...

10 days ago, when I last held forth on this particular topic, we'd figured out at least one reason why my VHF reception was so poor...my supposed 'consistent gain through the entire DTV channel spectrum' Antennas Direct ClearStream 2 was in fact fundamentally a UHF-only unit. The Winegard YA-6713 VHF antenna that KTVN had brought over is unfortunately out of production, and its YA-1713 successor is undesireably oversized for my diminutive abode. However, I also discovered AntennaCraft's Y5-7-13, which is still available for sale and has YA-6713-reminiscent dimensions and specifications. The Y5-7-13 arrived yesterday, and I installed it today.

As a reminder, here's what my home looks like:

The ClearStream 2 is mounted to the horizontal beam to the right of the front door, as you're facing it from the outside:

And, after consulting with AntennaCraft's Valerie Needom and with KTVN's Jack Antonio, I decided to directly attach the Y5-7-13 to the horizontal beam to the left of the front door:

A splitter/combiner merges the two antennas' signals, ahead of the coax cable that enters the dwelling. I've gone ahead and re-pointed the ClearStream 2 directly at KRXI's UHF tower on Peavine Peak (~30° compass heading), since the Y5-7-13 in its mounted position conveniently points directly at the ABC (KOLO). CBS (KTVN) and NBC (KRNV) towers on Slide Mountain (~90° compass heading).

Based on my recent measured results, I was hopeful I'd finally be able to reliably tune in KOLO's broadcasts. And indeed, KOLO's NTSC reception on VHF channel 8 is much better than before; I'd rate it somewhere between 'good' and 'very good' now. But I'm still not able to tune into KOLO's ATSC signal on VHF channel 9, as the following Windows Vista Media Center screenshots point out (sorry, I no longer have the Sencore AT1506 on-site):

Note that when I captured the screenshots, my laptop's HP ExpressCard tuner was directly attached to the output of the splitter/combiner (thank goodness for battery-operated portable gear); as such, the measured results don't even incorporate any potential incremental attenuation caused by the home's internal coax wiring topology.

At this point I'm baffled. Admittedly, KOLO's ATSC signal had previously measured 8 dB mV lower than either KOLO's NTSC signal or KTVN's digital beam (and 14 dB mV lower than KRNV's ATSC broadcast, for that matter), using the Winegard YA-6713. And admittedly I'm using AntennaCraft's Y5-7-13 directly mounted to a wood beam, not Winegard's YA-6713 mounted to a pole. But given that I was previously able to reliably tune in signals less than -28 dB mV in strength, and given than I now have an 'official' VHF antenna at my disposal, I don't know why KOLO's ATSC beam still eludes me.

Industry scuttlebutt suggests that KOLO's tower was designed for channel 8 and is sub-optimal for channel 9, and that KOLO will therefore move its ATSC signal from channel 9 to 8 after next February's NTSC sunset date. I'm cautiously optimistic that this migration will finally lead to reception success on my part, although given that the ATSC broadcast signal will still be ~150 kW weaker at the source than its NTSC predecessor, there are no guarantees. And it'd sure be nice if KOLO's engineering team was as supportive as Jack Antonio and his counterparts at KTVN...KOLO doesn't even bother responding to my emails and voicemails. Then again, though, neither did KRNV when I inquired as to why they weren't broadcasting the Olympics in surround sound...