April 28, 2015 at 12:52 pm #10094radiogeekParticipant
OK, that helps a lot. Class A to become primary service is an issue of physical distance to secondary adjacent channels, and total power to the translator as a fill in is limited to 99W, even if a directional antenna is used to protect KLVU.
I wonder if there is a tower K296FT could move to to get rid of the distance to secondary adjacent channels issue and become primary serivce? But of course if it were technically possible there still would have to be a filing window.April 28, 2015 at 1:26 pm #10095
The minimum spacing for a new Class A to a second adjacent existing Class C (106.7) is 59 miles, to a second adjacent existing Class C0 (107.5) is 53 miles. 73.207
The minimum short spaced distance in this case is 55 and 50 miles, respectively.
Clearly, with KLVU to the southeast and KRQT in Castle Rock to the north as nearby co channels, 107.1 will never be anything more than it is, secondary service.
These co channels are the reason why even at 99 watts you can only squirt out about 28 watts worth to the north and southeast (as shown on the contour map by the non directional 28 watt and directional 99 watt contours being the same in those directions). To the west you have another co channel translator in Seaside and to the east there is one being built in Parkdale. There is also an application for an LPFM on 107.1 in Madras.
107.1 in Portland could support an LPFM and originate its own programming, but in order for that to happen is a long and convoluted process which would entail lots more money than it is worth and would also mean the present license holder would have to give it up with no assurance they would get it back as it would become a new opening and anyone could compete for it.
So as I said, forget it. It isn’t going to happen. It’s just a bargaining chip for MetroEast should they prevail or partner up in the remaining LPFM MX for 100.7 MHz. MetroEast would not have to give up the translator, as their application for LPFM meets the requirements for not having to divest the translator (60 dBu’s overlap) provided they run the 100.7 LPFM programming through it. I don’t know when KXRY’s lease runs out with MetroEast and it is also unlikely that MetroEast will win the 100.7 LPFM outright, as there are 6 applicants on the docket.April 28, 2015 at 1:41 pm #10096radiogeekParticipant
Wow. Less than 3 miles to more than eighty is quite some jump. Got it.April 28, 2015 at 3:05 pm #10097
Oops. Got that switched. I listed first adjacent distances. Second adjacent is a little less but still results in the same problems.
2nd adjacent numbers are 59 and 53 miles.
maximum short space numbers are 55 and 50 miles.June 1, 2015 at 4:45 pm #11178Jeffrey KoppParticipant
This afternoon my cabbie was listening to Xray while we drove from downtown to Milwaukie.June 16, 2015 at 12:22 pm #11653
Well they’ve been on the air for quite a while and I’m amazed that there are still some operators at KXRY that don’t know how to do a legal ID at the top of the hour. Sure, the chances of getting fined are pretty slim, but still.
Also, I have yet to hear them properly ID the translator (required three times a day), but that could just be my listening patterns haven’t caught one yet.
There must be a pretty low barrier to entry to get on the air at XRAY, or at least whatever the requirements are they aren’t based in speaking ability, programming fluidity, or board operating skills. Some of these people are pretty good. Some of them are amongst the worst I have ever heard on the air. Sorry, no names or time slots. Just a general observation made over months of listening.July 29, 2015 at 12:05 pm #12644
I was listening to Thom Hartman’s program on 107.1 Tuesday on my trip out to Hillsboro. I was quite disappointed in the signal quality coming out of the tunnels on US 26 and heading through Sylvan and beyond heading towards SW 185th. The signal never really became listenable, even out by the intersection of 217. I would imagine a stationary receiving situation would remedy the noise, which was quite objectionable, but mobile reception is the life blood of FM radio these days if not forever.
I would think the signal would be more cooperative going out Barbur Blvd, at least it has the few times I’ve listened in. Haven’t checked on the Beaverton-Hillsdale Highway, but both of those routes are more in the heart of the major lobe. U.S. 26 is close to the null created by topography to the northwest of the antenna where the ridge rises in elevation, becoming higher than the translator’s transmitting antenna. So I shouldn’t be surprised but I was disappointed.
Antenna: Dual diversityJuly 29, 2015 at 12:25 pm #12645semoochieParticipant
I didn’t realize they still made diversity antennas.July 29, 2015 at 12:37 pm #12646jr_techParticipant
How is the selectivity of your vintage Alpine? I’m guessing that some of the noise might be caused by close proximity to the Sylvan site (106.7 IBOC and 107.5 IBOC)… just a WAG, however.July 29, 2015 at 3:08 pm #12655
I was up way past my bedtime yesterday, and I noted that the programming on K296FT ended, but the carrier never dropped.
The signal strength of K296FT heading out west over TV highway and to my house leaves something to be desired. I wonder whether it is possible that one of the tower legs partially shadows the signal in this direction.July 29, 2015 at 3:16 pm #12657
“I didn’t realize they still made diversity antennas.”
My car is a ’98, semoochie. Before shark fins, etc.
Alpine C43 OEM. Can’t find the specs, but I never have much adjacent channel distortion. It’s more likely to pick up weak on channel signals and you end up hearing multiple signals on one channel. But I don’t know if your guess is correct because through the canyon, there’s a lot multi path and let’s face it, the 107.1 signal isn’t propagating well to the NW along that rising ridge, so the tuner is just blurting out what it’s getting on 107.1.July 30, 2015 at 10:09 am #12682
I had been curious about what is inside those “shark fin” antennas. Photos that I have seen of tear-downs of these antennas show that they are microwave antennas designed for satellite radio and GPS reception. I have noticed that cars with the shark fin antennas also have rear windshield antenna elements; this is what is being used for terrestrial radio reception.July 30, 2015 at 12:01 pm #12683
That’s precisely what I’ve got. The rear in-window wiring supports AM/FM/WX/keyless entry and defrosting. This diagram is not exact, but close.August 4, 2015 at 12:43 pm #12813
About 20 years ago, Electronics Now ran a construction article on a “Diversity FM Adapter” that was designed to connect a standard FM car radio to two antennas. The adapter circuit used a PLL tone detector to detect the presence of the 19 kHz stereo pilot in the received audio. Any dropout of the pilot into the noise floor would cause the PLL to lose lock, and that would make the circuit switch antennas. Of course, this system would not work with monophonic broadcasts.
Do you know, did commercial diversity FM systems like the Alpine work in the same way? Or, did they actually have two complete FM receivers, with received signal strength and/or noise levels being used to select which receiver ended up playing through the speakers?August 11, 2015 at 4:14 pm #12978
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