Hi all...
Over the last couple days I've recorded a few clips from KBRT, as heard within 1/8 mi (0.2 km) of 32.761°N 116.947°W, with my Tecsun PL-398mp. All but one use the Select-A-Tenna, the other one is using only the radio's internal loopstick.
https://www.youtube.com/watch?v=mHRYXyvAzL8 - Feb 26 sunset signoff announcement. The transmitter is switched off about 32 seconds after the music ends. KCBS is also heard through much of the clip, getting clearer when KBRT is switched off.
https://www.youtube.com/watch?v=M7JxaM0eYfQ - Feb 27 sunset signoff. Unlike the previous day, the signal seems to fade its way out over several seconds to a certain point, THEN gets switched off.
https://www.youtube.com/watch?v=GtqR3TJPAOg - Feb 27 night/day pattern change ~6:53 am. After the switch, KBRT is easily on top, but KCBS can still be heard underneath. Before the switch, KBRT is still audible, but competes with KCBS, with KCBS sometimes on top especially at the beginning of the clip.
https://www.youtube.com/watch?v=hQrnpMrfCcM - Feb 28 signon (on night pattern from Catalina). KBRT, even at low power, CAN be heard here just south of El Cajon, about 92+1/3 mi E/SE of the Catalina site. KCBS is also heard simultaneously.
So, since I could still hear KBRT from here on night pattern, how much closer would one need to be for it to be a listenable signal for most non-DXers - maybe 3 or 4 times closer? Or, am I underestimating how far stations can still be detected beyond their clear-signal zone?
I do realize it's not a sudden cliff - if a $500k military radio with a beverage array can't detect QRSS CW or PSK31 (whichever one works with fainter signals) at 200.000000 km, a Coby or other terrible brand radio (one that can't get KNX at Columbia Park's softball field, and with which KLNV is wiped out by KOGO, even with IBOC off, at Emerald Hills Park's tennis courts) won't get a perfectly clear signal at 199.999999 km. How quickly do they drop from noise-free to undetectable even with a BFO, assuming same radio with stock built-in antenna, constant ground conductivity (like 15 mS/m) and constant noise level (nearest population density greater than 16 km^2/person is so far that two 50kW 540's with 180° antennas will fit between you and there, at least daytime)?
Aaaanndd... I recorded the location switch from Avalon to Costa Mesa at noon.
https://www.youtube.com/watch?v=UMyhL0rdu3Y
This one was recorded using only the Tecsun's built-in ferrite antenna - the SAT was not used. When KBRT was transmitting from Catalina, they clocked in at about 48 dBµ on the Tecsun. After the switch to Costa Mesa, they're at about 32-33 dBµ, and noticeably noisier.
(I would have been interested in trying, with the SAT, for KCBS at noon while KBRT was off, but I wanted the switch recorded barefoot to show typical normal reception. I wonder if there's some way I might get that chance anyway sometime soon?)
KBRT was just barely edging out KNX as the strongest L.A. area station heard here midday, but now they're approximately competitive with KLAA, making KNX the current strongest L.A. groundwave signal here. KFI is typically a few dB, give or take, behind KNX, in spite of being 12 miles closer. Interesting to mention, also, is KDIS - they're about 22-25 dB weaker than KNX, in spite of being about the same distance, close on the dial, and sending effectively 80 kW toward me, based on their RMS field vs field in my direction.
Sometime I hope to record several of the L.A. area legal TOH IDs as heard in the daytime here, and maybe post a compilation video for comparison of their signal strengths.
Over the last couple days I've recorded a few clips from KBRT, as heard within 1/8 mi (0.2 km) of 32.761°N 116.947°W, with my Tecsun PL-398mp. All but one use the Select-A-Tenna, the other one is using only the radio's internal loopstick.
https://www.youtube.com/watch?v=mHRYXyvAzL8 - Feb 26 sunset signoff announcement. The transmitter is switched off about 32 seconds after the music ends. KCBS is also heard through much of the clip, getting clearer when KBRT is switched off.
https://www.youtube.com/watch?v=M7JxaM0eYfQ - Feb 27 sunset signoff. Unlike the previous day, the signal seems to fade its way out over several seconds to a certain point, THEN gets switched off.
https://www.youtube.com/watch?v=GtqR3TJPAOg - Feb 27 night/day pattern change ~6:53 am. After the switch, KBRT is easily on top, but KCBS can still be heard underneath. Before the switch, KBRT is still audible, but competes with KCBS, with KCBS sometimes on top especially at the beginning of the clip.
https://www.youtube.com/watch?v=hQrnpMrfCcM - Feb 28 signon (on night pattern from Catalina). KBRT, even at low power, CAN be heard here just south of El Cajon, about 92+1/3 mi E/SE of the Catalina site. KCBS is also heard simultaneously.
So, since I could still hear KBRT from here on night pattern, how much closer would one need to be for it to be a listenable signal for most non-DXers - maybe 3 or 4 times closer? Or, am I underestimating how far stations can still be detected beyond their clear-signal zone?
I do realize it's not a sudden cliff - if a $500k military radio with a beverage array can't detect QRSS CW or PSK31 (whichever one works with fainter signals) at 200.000000 km, a Coby or other terrible brand radio (one that can't get KNX at Columbia Park's softball field, and with which KLNV is wiped out by KOGO, even with IBOC off, at Emerald Hills Park's tennis courts) won't get a perfectly clear signal at 199.999999 km. How quickly do they drop from noise-free to undetectable even with a BFO, assuming same radio with stock built-in antenna, constant ground conductivity (like 15 mS/m) and constant noise level (nearest population density greater than 16 km^2/person is so far that two 50kW 540's with 180° antennas will fit between you and there, at least daytime)?
Aaaanndd... I recorded the location switch from Avalon to Costa Mesa at noon.
https://www.youtube.com/watch?v=UMyhL0rdu3Y
This one was recorded using only the Tecsun's built-in ferrite antenna - the SAT was not used. When KBRT was transmitting from Catalina, they clocked in at about 48 dBµ on the Tecsun. After the switch to Costa Mesa, they're at about 32-33 dBµ, and noticeably noisier.
(I would have been interested in trying, with the SAT, for KCBS at noon while KBRT was off, but I wanted the switch recorded barefoot to show typical normal reception. I wonder if there's some way I might get that chance anyway sometime soon?)
KBRT was just barely edging out KNX as the strongest L.A. area station heard here midday, but now they're approximately competitive with KLAA, making KNX the current strongest L.A. groundwave signal here. KFI is typically a few dB, give or take, behind KNX, in spite of being 12 miles closer. Interesting to mention, also, is KDIS - they're about 22-25 dB weaker than KNX, in spite of being about the same distance, close on the dial, and sending effectively 80 kW toward me, based on their RMS field vs field in my direction.
Sometime I hope to record several of the L.A. area legal TOH IDs as heard in the daytime here, and maybe post a compilation video for comparison of their signal strengths.