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This from All Access:
CAMERON CRAVEY has closed on the sale of K236CA/TACOMA, WA (now K248DD/PORTLAND, OR) to CRAWFORD’s KPHP RADIO, INC. for $27,500. The buyer is moving the translator to rebroadcast Religion KKPZ-A (1330 AM THE TRUTH)/PORTLAND.
The translator is now on the air. 97.5. Read the story and see a nice picture here:http://crawfordbroadcasting.com/Local_Oscillator/November%202016%20Local%20Oscillator.pdf
Probably little chance of logging it here on the N Coast as I see the pattern is “very” directional to the SE, little signal going NW. Plus I have 97.5 co channel (Lincoln Beach) that is quite good here.Most of the fare on Otter Rock booms into the North Coast. I do get a fair number of FM translators relaying their AM’s, like KXRO Aberdeen WA, 2 or three out of Longview, plus a couple locals. Those 250w translators are everywhere.Seattle also has a bunch.
Mt. Scott to Swan Island has line of sight even though it is the back of the pattern. Distance is about 17 km.
We thought we could make an 11 gHz microwave hop work between Swan Island and Mt. Scott. Couldn’t pan it in. One of the Fremont Bridge supports was in the way.
I’m picking up K248DD in Goose Hollow with a so-so but listenable signal. Until today, I used to receive K248CN Ariel WA (a translator for Northwest Public Radio’s KSWS 88.9 Chehalis WA) on 97.5 MHz.
I can receive K248DD from my location in Hillsboro, but I have to do all of the following:
1) Position the Yagi very slightly north of due east
2) Mistune the Signal Sleuth preamplifier by about 1 MHz (either above or below 97.5 MHz)
3) Carefully set the gain on the Signal Sleuth to null out K248BSIt puzzled me why deliberate mistuning of the RF preamplifier is necessary to make K248BS dissapear. I came up with the hypothesis that mistuning the amplifier creates just the right amount of phase shift so that the residual amount of K248BS picked up by the antenna and downlead can cancel out the K248BS signal that leaks into the tuner and the coax connecting the tuner to the amplifier.
Interesting! I suspect that you are correct that the mis-tuned amp with variable gain provided sufficient out of phase signal to null out K248BS. In the past, I have used a signal from an attic mounted FM-6 combined (through a variable attenuator and phase network) to null out unwanted co-channel signal from my main antenna (APS-9). Works pretty well most of the time.
As an experiment, I will try inserting a short length of coax before the amplifier and paying close attention to how the tuning “sweet spot” moves.
KISN-LP sounds like a blowtorch (with full quieting) compared to K248DD from my location.
My delay line (extra coax) experiment caused the “sweet spot” to disappear completely.
More recently, I drove into Portland on 26, and I started hearing K248DD as soon as I exited the tunnel. The reception was laden with multipath, and it continued to be this way as I headed southbound on I5, despite that I could see some tower beacons that I think were the Mt. Scott towers.
K248DD is not receivable in the area near the Burlingame Fred Meyer, as it is covered up under IBOC hash. Heading south toward Tigard on Barbur Blvd., K248DD returns, but there is a hill after which K248BS (Newberg) dominates the frequency.
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