September 17, 2018 at 10:12 pm #39407
Checked the spectrum later than usual today.
KOXO-CD (RF 15) is back on the air tonight. First time I have seen it up since September 7th.September 25, 2018 at 7:11 pm #39524
KOXO-CD (RF 15) is essentially off the air this afternoon. There is a signal 35 dB below the normal amplitude on that channel with a pilot frequency within a fraction of a Hz of KOXO’s former frequency (*). So, I assume that the station may have had a power amplifier failure of some type. In any case the exciter’s signal seems to be getting through to the antenna.
(*) I have a good GPS disciplined 10 MHz reference standard plus a HP synthesizer. I use this combination to zero beat and measure the pilot carrier of DTV signals. KOXO-CD has been notable in that its pilot frequency has been within a 1/2 Hz of the correct value any time I have checked. For the moment, I assume that KOXO is using a GPS disciplined exciter. In any case, it has been very accurate, perhaps more accurate than I can measure.September 26, 2018 at 8:47 am #39529
Interesting! Indeed the signal that I observe dropped from S-8 down to zero (indicated S-1) on the tiny meter under the dx cat’s right paw.
41-1, 41-2, 41-3 and 41-4 (all rebroadcasting KWVT-17) are missing on my tv.
What is the correct frequency for the reference signal? I get a decent beat tone 0.310 to 0.311 mHz up from the lower edge of each digital channel.September 26, 2018 at 10:31 am #39531
Clause 8.5.1 of the ATSC document A/54B gives the nominal frequency of the pilot signal as 309.440,559 kHz above the lower channel edge. This is a “Recommended Practice” value, not a spec.
There doesn’t seem to be any firm specification for the pilot frequency. In the years when analog was still on the air, the FCC itself required a value different from nominal when there was a lower adjacent channel analog station. The ATSC still recommends small offsets under certain situations.
I wrote the IEEE Recommended Practice for measuring DTV mask compliance and the DTV measurement sections of the NAB and SBE engineering handbooks. After a good deal of study, I concluded that the only firm FCC frequency spec for DTV transmitters is that they stay within the emissions mask.
The DTV standard has very few firm specifications and many, many “Recommended Practices”. Yet, it seems to work well.September 28, 2018 at 12:08 pm #39551
Thank you! That also explains why the pilot frequency for OTA 33 (ch 32) was found to be at 584.332 mHz years ago.
Do you observe a waver in frequency and intermittent transmission of the pilot of ch 36? (602.312 mHz)?September 28, 2018 at 8:38 pm #39553
1) When the analog TV transmitters were on the air, the DTV pilot had to be frequency locked to the lower adjacent analog TV’s visual carrier with a precise offset. Analog TV transmitters themselves operated with two offsets: 10 KHz low, and 10 KHz high as well as on nominal frequency (these offsets alleviated interference issues in the deep fringe area). All told then, affected DTV transmitters operated with a 12.7 kHz or a 22.7 KHZ or a 32.7 KHz positive (higher) offset from the normal pilot frequency depending on the analog transmitter’s offset. Channel 33 at that time apparently was operating with a 22.7 kHz offset. My last close look was on last June 15th when I found channel 33 to be 9 Hz high from the normal pilot frequency.
2) The notes from that June 15th measurement session say that channel 36’s pilot was “irregular”. I looked at it again tonight. From what I can tell it has an irregular FM modulation of about 10 Hz peak to peak with an irregular period of about 0.8 seconds. Both the deviation and the period seem to vary somewhat. I made its nominal pilot frequency as 602.310,125 MHz.October 1, 2018 at 9:47 am #39561
I “measure” 602.311,79 with my Icom… so I guess it reads almost 2kHz high at this frequency.
The station is still intermittently turning on and off, which can’t be good for listeners. Verified that the tv reception of KEVE does stop when the pilot abruptly quits.October 3, 2018 at 5:15 pm #39592
KOXO-CD is back up to full power this afternoon for the first time since Sept. 25th.October 10, 2018 at 3:18 pm #39713
I definitely do not understand.
KOXO-CD, KORK-CD and KORS-CD have not been on the air since last … what ever (their story is Feb 17, 2018). Yet today Watch TV files a Children’s Programing Report with the FCC that states these stations have been transmitting 4.5 hours of children’s programming a week.
How does this work? Some sort of legal oddity? Can anyone explain?October 10, 2018 at 3:34 pm #39714Andy BrownParticipant
Not necessarily in order of being asked, but here’s my guess:
“Can anyone explain?”
Sure. Watch-TV can but they won’t be asked to because
“How does this work?”
The F.C.C. is so understaffed that checking much of anything that doesn’t deal with interference complaints (and I don’t mean just radio and T.V., I mean everything including satellite, terrestrial microwave, cellular, etc.) is probably not going to be done. The public can read a lot of stuff because it’s automatically uploaded to their on line databases, but not necessarily read by anyone at the F.C.C. which also means connecting the dots between STA’s and ongoing filings of a nature such as what you are writing about.
“Some sort of legal oddity?”
Exactly. The big telecoms are the champs at gaming the system. They can afford the fines if they get caught.
Sorry. I know you were looking for a better answer, but when you only have two field agents for the entire west coast, you can imagine the ghost town atmosphere on 12th Street. A lot of the smaller stuff falls between the cracks and the big money players didn’t just start abusing the rules nowadays, it’s been a 70 year hobby of theirs.October 10, 2018 at 6:12 pm #39717lastdayParticipant
Someone help me out.
What in the heck is WatchTV? Never heard of it. Google points me to an AT&T streaming service with the same name WatchTV.October 10, 2018 at 6:39 pm #39718ScreamerParticipant
‘Watch TV’ is the name of a company that owns several low-power/class A TV licenses in Portland and Eugene. Many, if not all of them have been dark for a significant amount of time. However, the group received testing authority for the ATSC 3.0 TV standard and may be trying to resurrect themselves with that testing authority, perhaps with the hope of being added to the local cable and satellite.October 10, 2018 at 6:57 pm #39719lastdayParticipant
Ok, thanks. It took a little digging but I found this archive of a website.
Whoever or whatever they are, apparently they can’t afford an online presence. And if ATT has grabbed the name “WatchTV”, well, good luck with that.
Wikipedia refers to it as both “WatchTV” and “Watch TV”.
A foreign business entity registered in Texas. President and Secretary are Gregory and Wendy Herman of Southlake TX.
Registered Agent in OR: Michael J. Bragg of Lake Oswego.
Thank you Internet.October 10, 2018 at 7:35 pm #39720
Actually the FCC rescinded WatchTV’s experimental ATSC3.0 STA on April 18, 2018 and told WatchTV to get all the stations on the air in ATSC1.0. At that time, a Silent STA was granted that was to run out on August 17th. In the April action, the FCC frowned on WatchTV and said not to ask to extend the silent STA beyond August.
However on Aug 15th WatchTV did apply for an extension to its Silent STA citing the lack of delivery of the new combiner required for their post repack channel assignments. Never mind that when WatchTV petitioned the FCC for an early move to its new channels, WatchTV said there was no problem with moving rapidly ahead. The second Silent STA is still “pending”.
Like Andy Brown noted, enforcement is often lax.October 13, 2018 at 12:19 am #39744washnotoreParticipant
KWVT future weather channel is now being Quadcasted on KOXO-CA.
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