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Winter reception better?

Schroedingers Cat said:
pianoplayer88key said:
I remember being about 5 km east of 1170 KCBQ's transmitter a few weeks ago, and I could hear what sounded like skywave fading on their signal.

In the daytime?

Were you in a null? Were you driving near high tension towers?

I was at 32°53'4.86"N 116°51'57.6"W. Also it was around 5pm or so. (The station does its 50kW-to-2.9kW powerdown Nov & Dec at 4:45pm.) According to the monitoring points specified in their authorization (scroll down to the last couple pages, assuming it loads - if not try http://licensing.fcc.gov/cgi-bin/ws.exe/prod/cdbs/pubacc/prod/app_det.pl?Application_id=1342067 and click from there), I was at the location described as their 102.5°, 5.68 km, 0.63 mV/m point.
It was actually more like 5.7 km / 3.5 mi distant, at a bearing of 102° from KCBQ (282° to them). Their 100° field @ 1 km is 10.36 mV/m Theoretical, 20.93 Standard and 24.34 Augmented. (RMS is 583.3 mV/m Theoretical and 612.9 mV/m Augmented at night.)
Also, I was on a bike - not driving. :) I can't make out any above-ground utility services nearby, unless I'm looking for the wrong clues.
KCBQ shares towers with 910 KECR - according to the FCC their electrical height is 90° at 910 kHz and 115.7° at 1170 kHz.
 
One thing I noticed (re: KCBQ's monitoring point) was that using various online distance/azimuth calculators, vs. what the FCC said the monitor point location was, didn't exactly agree.  Is it possible that seismic activity could have shifted things (this IS southern California, after all), or are there different types of coordinates used? (I've seen references to NAD27 and NAD83, IIRC, on FCC's site.)  This was for other monitor points as well.  Also I've noticed that when I put in FCC's coordinates on Google Maps, they aren't where it seems they should be.  For example, KCBQ's "coordinates" show up as being toward the southeast end of the property, and coordinates for non-directional stations are rarely right at the base of the tower.
(ran out of edit time; this should have gone with the previous post)
 
I think the calculator sites may use decimal degree equivalents vs. DMS for the FCC coordinates. But small amounts just may be GPS imprecision.

In any event, you are in a deep null. 3.5 miles to the 0.63 mV/m contour is pretty deep. In deep nulls you may have phase distortion that sounds like fading.
 
Schroedingers Cat said:
I think the calculator sites may use decimal degree equivalents vs. DMS for the FCC coordinates. But small amounts just may be GPS imprecision.

In any event, you are in a deep null. 3.5 miles to the 0.63 mV/m contour is pretty deep. In deep nulls you may have phase distortion that sounds like fading.

Yeah I can see that. :) Also there was a little co-channel interference noticeable there, as well. BTW I was only briefly visiting that site, so I "WAS" ;) in a deep null. Here I'm about 9.3 miles at 187° heading from their transmitter, and it's a much stronger signal. The only "fading" is a ~72-74 Hz or so flutter caused by their carrier being off-frequency with the co-channels under them (the strongest being KLOK San Jose) when I null them.
Speaking of deep nulls, I'm quite sure that's not even close to the deepest null a station has. :) I was thinking ... are there any 50kW (or more powerful for out-of-USA) stations with nulls so deep that you could use a sensitive communications receiver with a 50-foot-per-side tuned box loop, be completely unable to detect anything even with QRSS CW and an all-saltwater path, and yet be close enough so that if you were using a beverage the other end would be physically touching one of their towers?

Interesting about the GPS coordinates. Also I wonder if I'm sometimes trying to be a little too precise? For example, if I go to 32°53'43.568027"N 116°55'33.149326"W on Google Maps, it's supposed to put an indicator at the base of the 3rd tower (counting from west) in the 4-in-line portion of the array, which it does. (Google's satellite view at that location isn't high enough resolution for me to be able to tell which side of the tower base the pointer is on, or whether it's in the exact center of the guyed tower's base, though, and when overlaying adjacent coordinates I can only go to about 2 or maybe almost 3 decimal places on the seconds before it lays the indicators on top of each other.) However, it also puts a marker a whopping 249,661 millimeters away (according to the Google Maps measuring tool) at an address up the street. When I try to pull up the coordinates on my Android phone's Google Maps app, it ONLY pulls up the address - it will NOT give me the exact location of those coordinates.

And speaking of field intensities ... I noticed you apparently have a FIM. I don't know if you by any chance have one of those newer Si4734-based DSP Tecsun radios, but I was thinking ... Any idea what the approximate field might be at a location where, for example, a high-end comm receiver like a Drake, Collins, Icom (or something like a military unit that can handle relatively strong signals without overloading, intermodding, desensing, etc) would behave like this (start ~0:51 or ~2:01) or this (start ~1:04 or 0:45) WITHOUT any antenna connected at all? :) Or do most FIMs not read field intensities that high? ;) (I was about a hundred meters from KCBQ's nearest tower right in the middle of their main lobe, using a Select-A-Tenna plus an inductively-coupled makeshift "beverage" disguised as an overhead utility line.) It's interesting how patterns can be set up so you don't have to go very far from having your radio being totally overloaded to having a weak signal. :)
 
A couple of engineers have let me borrow their FI meters for extended periods when they weren't using them to keep all the switch, potentiometer, and other contacts clean and keep dust deposits and metal whiskers from shorting out the variable capacitors. I've thought about buying a used one online, but you never know what you are getting and the thing would probably need an overhaul and professional recalibration which would be expensive. Another engineer offered to give me one that had a problem with the meter spring which made it nonlinear in one place and couldn't be repaired. I wish I'd gotten it anyway, but he left the company and has since passed away.

Unless you are going to make some money with one, an FI meter is a pretty expensive toy.
 
Sounds to me like you are going through most of the motions you would need to assist an engineer with proofs of performance, conductivity studies, etc. There are some rigorous things you would need to be taught, especially if you used the older FI meters. But I know someone with much less technical knowledge that worked as an assistant to a top tier consulting engineer for some new 50 kW complex directional antenna proofs. If you didn't go off on too many tangents and what-ifs, I think you could do it now.
 
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