In the process of doing this, I also tidied up the FCC's M3 sequence file, which defines the distinct areas of ground conductivity across mainland U.S., Hawaii, Canada, and Mexico. Missing Great Lakes summer conductivities were also ferreted out from other sources. With that in hand, I created a nice Google-based HTML map of U.S. ground conductivities and thought I would share it with you. It's fully zoomable like all Google maps.
It can be downloaded from the link at the upper right of this blog. It's self-contained like my pattern maps. Unzip the file and click on the HTML file to view.
Hope you enjoy it.
 |
| Static rendering of the FCC's M3 ground conductivity map. |
30 comments:
This is definitely much better than what I've tried to do. Somewhere on the FCC's site is an option to download a large wall-sized version of their ground conductivity map. It's cut into multiple JPG sections, and when i try fitting them together, they don't fit well. (That's including trying to trim off the white space arond the edges.)
Now if only I could use the google maps measure tool, search for my QTH and transmitter sites, & see the path between me & other stations.... :)
73, Stephen
I guess no one has specific conductivity data for Salton Sea and Great Salt Lake, though?
I see you've included Mexico. Could this be a start toward maybe finding a way to include Mexican stations in your other programs/lists/patterns? :)
Speaking of ground conductivites outside North America, have you seen this?
https://www.itu.int/dms_pubrec/itu-r/rec/p/R-REC-P.832-2-199907-S!!PDF-E.pdf
I've noticed that they state the MF ground conductivity of the Dead Sea as 27,000!
Hi Stephen,
Glad the map is useful.
The Greeat Salt Lake is shown as 15,800 in some reference I have. I have not included it yet.
Actually, Mexico was already in the FCC database. Generally, I found many segments that didn't meet perfectly and have corrected them.
The rest of Latin America is in the R2.seq file, but they have changed the way they detail the information. Have not found it usable yet.
Bill
Hi Bill,
Yesterday I took a few radios and went around a few places in east San Diego county, and also around the Salton Sea, to check some signal strengths. I recorded some videos, but need to do some editing and decide which portions I'll upload. (Also I have a newer camera with a larger (1”) sensor that can record 4K (the Panasonic FZ1000), but for today I set it to just 720p.)
The first place was in Pine Valley, at 32.822203, -116.529171, and I was there at around 8:57am. Some signal strengths on the Eton Traveler III were:
540 xesurf ~ 32 dBµ
600 kogo ~ 35 dBµ
640 kfi ~ 26 dBµ
690 xeww ~ 36 dBµ
760 kfmb ~ 43 dBµ (but noisy probably from the camera)
800 xespn ~ 27 dBµ
860 xemo ~ 35 dBµ
910 xeao/kecr ~ 18 dBµ (but wildly swinging due to co-channel)
950 xekam ~ 25 dBµ
990 xecl ~ 22 dBµ
1000 kceo ~ 21 dBµ
1030 xesdd ~ 24 dBµ
1040 kurs ~ 16 dBµ
1050 xed ~ 22 dBµ
1070 knx ~ 26
1090 xeprs ~ 28 dBµ
1110 kdis ~ 14 dBµ
1130 ksdo ~ 23 dBµ
1170 kcbq ~ 28 dBµ
1210 kprz ~ 21 dBµ
1230 kxo ~ 18 dBµ
1240 knsn ~ 22 dBµ
1270 xeaz ~ 25 dBµ
1300 krop ~ 18 dBµ (but hit by some noise source)
1310 xec ~ 19 dBµ
1360 klsd ~ 29 dBµ (but noise)
1390 xekt ~ 33 dBµ
1420 xexx ~ 30 dBµ (with the camera about 6 inches away it was 36 dBµ & swamped by noise, but I had to have the camera that close to read the display outdoors)
1450 kfsd ~ 14 dBµ
1470 xercn ~ 33 dBµ
1490 kgba ~ 12 dBµ
1550 xebg ~ 16 dBµ
1630 xeut ~ 20 dBµ
1700 xepe ~ 30 dBµ
Next, I started heading toward Salton Sea via routes CA-79 and CA-78, and stopped at a couple spots on the way there to check some signal strengths, looking to try to find places where the weakest “strongest pests” were.
The next spot I quickly stopped at was on CA-79, at 33.889515, -116.576031, around 9:28am. Signal strengths:
1700 xepe ~ 34 dBµ
1470 xercn ~ 30 dBµ
1390 xekt ~ 27 dBµ
1360 klsd ~ 31 dBµ (but some noise source)
1280 kfrn ~ 11 dBµ
1240 knsn ~ 24 dBµ
1210 kprz ~ 28 dBµ
1170 kcbq ~ 32 dBµ
1130 ksdo ~ 30 dBµ
1090 xeprs ~ 18 dBµ
1070 knx ~ 26 dBµ
1050 xed ~ 22 dBµ
1040 kurs ~ 23 dBµ
1030 xesdd ~ 31 dBµ
1000 kceo ~ 27 dBµ
990 xecl ~ 20 dBµ
910 kecr/xeao ~ 19 dBµ (varying from co-channel)
860 xemo ~ 34 dBµ
830 klaa ~ 26 dBµ
800 xespn ~ 30 dBµ
760 kfmb ~ 44 dBµ (with some local noise from my equipment)
740 kbrt ~ 14 dBµ
690 xeww ~ 35 dBµ
640 kfi ~ 31 dBµ
600 kogo ~ 38 dBµ
540 xesurf ~ 32 dBµ
Next was also on CA-79 just south of Cuyamaca Lake, at 32.976589, -116.581515, around 9:52am.
540 xesurf ~ 32 dBµ
600 kogo ~ 37 dBµ
690 xeww ~ 37 dBµ
760 kfmb ~ 42 dBµ (with equipment noise)
910 kecr ~ 28 dBµ (here KECR was dominant over XEAO due to KECR's day pattern which throws a little lobe to the north/northeast.)
970 knwz ~ 34 dBµ
1000 ~ kceo ~ 34 dBµ
1090 xeprs ~ 28 dBµ
1130 ksdo ~ 30 dBµ
1170 kcbq ~ 31 dBµ
1210 kprz ~ 36 dBµ
1240 knsn ~ 22 dBµ
1360 klsd ~ 31 dBµ
1390 xekt ~ 28 dBµ
1470 xercn ~ 35 dBµ
1550 xebg ~ 22 dBµ
1630 xeut ~ 31 dBµ
1700 xepe ~ 32 dBµ
The next spot was several miles east of Julian on CA-78, at 33.090295, -116.579846 around 10:25am.
1700 xepe ~ 26 dBµ
1630 xeut ~ 26 dBµ
1550 xebg ~ 12 dBµ
1470 xercn ~ 27 dBµ
1450 kfsd ~ 20 dBµ
1390 xekt ~ 17 dBµ
1240 knsn ~ 18 dBµ
1210 kprz ~ 26
1170 kcbq ~ 29 dBµ
1130 ksdo ~ 25 dBµ
1090 xeprs ~ 22 dBµ
1050 xed ~ 27 dBµ
990 xecl ~ 25 dBµ
970 knwz ~ 28 dBµ
910 kecr / xeao ~ 14 dBµ
860 xemo ~ 22 dBµ
830 klaa ~ 16 dBµ
800 xespn ~ 18 dBµ
760 kfmb ~ 36 dBµ
690 xeww ~ 36 dBµ
640 kfi ~ 22 dBµ
600 kogo ~ 33 dBµ
540 xesurf ~ 25 dBµ
There was also a utility pole here, so I started to quickly check inductively coupled to that…
600 kogo ~ 70 dBµ
690 xeww ~ 70 dBµ
760 kfmb ~ 75 dBµ
1070 knx ~ 57 dBµ (barefoot it was 16 dBµ but practically inaudible due to noise from my equipment.)
But, the utility line was quite noisy, such that KNX was hit pretty hard by noise, and I probably could have heard traces on the 70+ dBµ signals. :/
Then, on my way to Salton Sea, I checked a little in the car while I was on CA-78, somewhere around a few minutes after 11am. I think I was approximately south or southeast of Borrego Springs, based on the time at my next stop (and I think I was probably going around 70+ or so on the wide-open highway or something like that.)
Anyway, I noted that 700-KALL was weak, but audible, on the stock radio-cassette in my '02 Civic LX. It was, iirc, a little better than 720 KDWN and 840 KXNT. I don't think I heard SF, although there might have been a chance I heard a carrier or something on 810 but I'm not sure. I tried KALL later by the Salton Sea, and wasn't able to hear it again for some reason. (I also couldn't get it at all on my PL-606 or Eton Traveler III. I didn't try the PR-D15 although I think I had it with me, partially due to not wanting to take too much time at each site.)
Anyway, next, my main purpose for the trip – to note the signal strengths for several stations whose signals cross the Salton Sea. The hope is that maybe noting the signal on one side vs the other could get some idea of its ground conductivity.
About 2pm, at 33.157915, -115.648894:
970 knwz ~ 54 dBµ (main target for this spot)
920 kpsi ~ 38 dBµ
1300 krop ~ 64 dBµ
1070 knx ~ 23 dBµ
830 klaa ~ 30 dBµ
640 kfi ~ 28 dBµ (but noisy from electronics)
This was the last spot I was able to check around Salton Sea. (There were several more I was unable to get to.)
Unfortunately I wasn't able to get to several of the exact spots I wanted to go to due to travel restrictions (like private property that Google maps showed as actual roads, or park land that I'd have to pay to get in, etc), but I did get several readings. I'd been using the Traveler III, but I switched to the PL-606 due to extreme difficulty in reading the Traveler III's display outdoors in bright sunlight.
About 11:42am, at 33.405951, -116.036815:
910 xeao ~ 33 dBµ
970 knwz ~ 64 dBµ
1230 kxo ~ 41 dBµ
1300 krop ~ 51 dBµ
main target: 640 kfi ~ 19 dBµ (18 on T3; it was near threshold on the PL-606 so I checked the T3 due to it being able to read lower and the numbers not being affected the same by desense)
About 11:50am at 33.416951 -116.049892:
main target: 830 klaa ~ 18-22 dBµ on PL-606 (with a trace of co-channel underneath, likely KFLT Tucson but it was essentially inaudible.)
About noon, at 33.498825, -116.090125:
830 klaa ~ 27 dBµ
970 knwz ~ 69 dBµ
957 desensing at 37 dBµ on PL-606
650 desensing at only 15 dBµ, so checking KBLU (main target this spot) is okay here.
560 kblu ~ 15 dBµ on PL-606 (13-16 on Eton Traveler III, checked due to bottoming out PL-606.)
About 12:24pm, at 33.532902, -116.028708:
main target: 1300 krop ~ 46 dBµ on pl-606
About 12:30pm, at 33.527450, -116.017776:
1270 kfsq ~ 41 dBµ on pl-606
About 12:38pm, at 33.535882, -116.008832:
970 knwz ~ 64 dBµ on pl-606
About 12:44pm, at 33.534077, -115.981175:
1230 kxo ~ 47 dBµ on pl-606
About 12:52pm, at 33.490172, -115.903294:
1430 kwst ~ 42 dBµ
About 1:24pm, at 33.292094, -115.584420:
main target: 640 kfi ~ 28 dBµ (why was it stronger on the far side of the Salton Sea, even though I was approximately on the same heading from the transmitter?)
About 1:35pm, at 33.263734, -115.562857:
600 kogo ~ 25 dBµ
760 kfmb ~ 27 dBµ
830 klaa ~ 28 dBµ (no noticeable trace of KFLT even though I was on the closer side of the Salton Sea, and the far side from KLAA.)
My last spot to check was across from the Subway & Chevron just south of I-8 near Jacumba Hot Springs, at 32.635405, -116.165685, around 3:54pm. Signals noted on the PL-606:
540 ~ 27,08
560 ~ 16,10
600 ~ 19,12
640 ~ 24,20
690 ~ 34,25
760 ~ 28,12
790 ~ 30,25
830 ~ 20,15
850 ~ 31,25
860 ~ 28,24
910 ~ 29,25
950 ~ 23,18
990 ~ 36,25
1050 ~ 34,24
1070 ~ 17,10
1090 ~ 25,20
1120 ~ 22,17
1130 ~ 17,08
1170 ~ 15,01
1230 ~ 29,23
1300 ~ 19,16
1360 ~ 20,05
1390 ~ 28,21
1420 ~ 21,01
1430 ~ 26,08
1460 ~ 20,17
1470 ~ 28,25
1490 ~ 26,25
1550 ~ 15,08
1630 ~ 27,21
1700 ~ 26,25
Unfortunately I was able to get a complete set of Salton Sea signal data, but hopefully there's enough (like for example signal strengths on the “far side” of the sea on some stations) to get some vague idea of its ground conductivity. Having a couple stations be stronger on the far side (830 KFLT and 640 KFI) though would pose a challenge. Also I'm still wanting to find a good site to do some DXing. I liked hearing KALL on CA-78, but I think KNWZ would be too much of a pest to be practical on portables. :/ Hmm….
73, Stephen
I just noticed a typo, in one of my stop points, instead of 33..... it should have been 32.889515, -116.576031 :)
Hi Stephen,
Thanks for the all the detailed signal strength reports. I would guess the Salton Sea is pretty high but somewhat less than the Great Salt Lake.
I'm traveling right now and for the next two weeks. Will be back in Rochester around the first of the month.
By the way I bought an Eton Traveler 3 on the way out of AZ. I like it a lot so far. It has a couple of little annoyances, but for the most part it is very sensitive and built reasonably well. Will do more testing soon.
73s,
Bill
Hi Bill,
Just wondering how things have been so far this spring/summer, primarily with radio-related things like the signal strength maps, DXing, etc. How's that Traveler 3 working for you? Were you ever able to receive stations like WNAX, CBK, etc. on your trip east (on any radio)?
I just missed an opportunity a couple days ago to get a CC Radio SW for $80 on ccrane refurbished, normally they're $140. There were a couple available and I got a message on the IRCA mailing list to their presence, but by the time I went to buy one on my computer, they were gone. Hopefully I can find a similar price-to-performance deal soon.
I recently replaced the stock radio in my Civic with a Pioneer DEH-X9600BHS. It has a CD player, HD radio, bluetooth, smartphone connectivity, satellite radio compatibility (although I'd need a tuner for that and a subscription which I didn't get). I'm for now a little disappointed with the performance on AM though, although I'm for now giving my installation the blame. For example, it's only marginally more sensitive than the stock radio. (I was hoping it'd be a much bigger difference, kind-of like what happens when you put a 3 or 4 foot loop up to something like the Sangean DT-400W or Sony SRF-59 or another similarly-small pocket radio.) Also it's no better on selectivity on first-adjacents. I was hoping I'd be able to hear 770-KCBC (5.3 µV/m) next to 760-KFMB (46.9 mV/m), 1180 KERN Wasco-Greenacres, CA (25 µV/m) next to 1170-KCBQ (123 mV/m), but all I get is splatter. Also I get a lot of engine noise covering up weak signals, and when I rev it it's even audible in the background of KCBQ.
Otherwise, if it wasn't for the splatter or engine static, I think I might be able to hear 700-KALL (6.1 µV/m) next to 690-XEWW, which is about a dB stronger than KOGO and a dB or two weaker than KFMB here. (I was able to hear it on CA-78 south of Borrego Springs with a weak but readable signal a couple months or so ago.) On the other hand, if I'm away from electrical interference and have the engine off, I sometimes get HD lock on 1070-KNX which according to your chart you sent me last fall for my location, is about 3.3 mV/m.
Here's a couple videos I put together, comparing the stock radio vs the Pioneer.
https://www.youtube.com/watch?v=BwL47Y_WjMI (530 to 1310)
https://www.youtube.com/watch?v=vLxWKFhfxuU (1320 to 1710)
They total about 41 minutes or so, because of doing a detailed comparison, and staying a bit longer on a few frequencies. Originally it was 1 video, but an error caused by the occupant of the chair in front of the computer resulted in there not being sound above 1310 kHz so I had to redo that portion.
Speaking of the chart ... would it be possible to obtain an updated chart for daytime for all signals (not just ones over 5 µV/m) for 32.76063889, -116.94583333? And would it be possible to include CPs and applications (and maybe the Mexican listings from FCC too, although it'd be nice to have a way to correct known errors, like transmitter sites, frequency, patterns, power, etc, after I have the list), maybe on a separate list? Btw that's the spot specified on the chart you sent last fall, which includes groundwaves over 5 µV/m plus skywaves. I'm especially interested in all groundwave signals.
Speaking of weak signals, I remember reading a post somewhere about someone who was able to hear some fairly distant station, using a Superadio III and a several-foot loop, at midday from Lubbock, TX, like 720-WGN, 750-WSB, 850-KOA, etc. I wonder what signal strengths might have been involved there? (Some of the stations he mentioned were over 1000 miles away. This was the same person that recommended a Pioneer car radio.)
I'm hoping to make another rural trip this summer somewhere in southern California (preferably in San Diego county but I might be able to branch out a little) to try some daytime DX at a time of year when skywave would be minimal. I'd like to find a place where the incoming semi-local signals are at their weakest, but I'm not sure how best to find that. Ideally I'd like a place where nothing is over 50-100 µV/m, but I think I'd have to go like way out into like central Nevada for that, so if I can find a place where the strongest signals are below 0.5-1 mV/m that would be good.
At one time I was working on a post / reply with some other radio-related things, but life got in the way and now I've forgotten where I saved it on my computer.
73, Stephen
Hi Stephen,
Good to hear from you. Nothing much to report on the trip east this spring. One day I tracked KFI-640 out of L.A. one day from Flagstaff, AZ far to the east of Grants, NM (almost all the way to Albuquerque). Their signal dropped out about noon. That's 600+ miles. Did not hear any of the other stations.
Okay on your new car radio, and thanks for the videos. I've gotten rid of my tired 2006 Ford Ranger truck (and unfortunately the great dash radio went with it) and bought a 2011 Honda CR-V. Its radio seems pretty good on AM, though a little less sensitive. It's definitely quieter with less spark noise. I'll do some comparing on the trip out west later in the summer. No external whip antenna. Not sure how they gather RF but will look into it.
I did a huge amount of work on the radio database program just before I left Arizona. I spent about 6 weeks almost full time working on improvements and new stuff. That was the final big push. All that remains is some sort of checkbox mechanism to turn on/off plots in the web browser. I'm hesitant to dive into that one for a couple of reasons. One, it won't scale well for tablets. Two, it's always been a simple matter of just creating a map with less stations during the creation process. Seems like a lot of work. And it's tedious code, outputting generated HTML. We'll see if I get a spark to start it at some point. For the map sets, I can just create either single station maps or group them in 5's or 10's. Only certain frequencies are a problem, like the graveyard ones, etc.
I am liking the Eton Traveler 3 very much is some respects. It has great sensitivity, better than any small (ultralight) radio I have used. The absence of soft-mute and channel change muting makes it tune like a real analog radio does. The dial lighting is atrocious though. Almost impossible to see in high daylight when outdoors. I found it couples very poorly to a loop too. But these DSP chip radios all have that characteristic.
I'll work up some charts for you for that latitude-longitude.
Bill
Stephen,
Okay on the 1000+ miles daytime AM reception. I think I have seen the same comments. I would definitely like to see (hear) that! Chances would definitely be better in the dead of winter for those circumstances.
Bill
Hi Bill,
You must have a pretty hot car radio then, or, the PR-D15 I used in AZ on my trip there with my parents in March was a dud. (I returned it.)
https://www.youtube.com/watch?v=9vTn3VaCJgo - Vail, AZ - PR-D15
https://www.youtube.com/watch?v=iH_kOzFSb4o - Gila Bend, AZ - PR-D15
In Vail, I was unable to hear 700-KALL, 660-KTNN, or 640-KFI.
In Gila Bend, I may have had a trace of 720-KDWN, I definitely had 700-KALL, possibly 660-KTNN, and a weak 640-KFI. These were a lot weaker than I would have expected them to be, though. (What surprises me is hearing KTNN in Gila Bend, but not in Vail, even though Vail is a little closer.)
I'm tentatively planning another one-day mini-DXpedition for this Wednesday or Thursday or Friday with my car radio and maybe a few others. A few spots I may want to check signals at could be Jacumba Hot Springs, CA (near I-8 across from the service station and Subway), highway 78 at Yaqui Pass Rd (south of Borrego Springs), Desert Center, a few miles or so east of Twentynine Palms (there's a restaurant on highway 62 that's just outside the 0.5 mV/m zone on the map you sent me), and maybe Quartzsite, AZ, or Mesa Verde (just west of Blythe). If I go as far as Quartzsite, I'd try to be there sometime during noon to 3pm window, and if so, what would be some suggested sites to check? (The main part of town itself is just over a 3 + 1/2 hour drive from me.)
My car uses, I believe, some wires in the windshield, I think the rear one. I'm considering possibly in the future putting a whip antenna on, as Bruce Carter on some other radio boards (the one who's gotten 1000 mile daytime reception in Lubbock, but with radios like the GE Superadio III and a 4+ foot loop) has said that whip antennas in his experience are much better. Also I've heard of cars that have like a little shark fin type thing on the back of the car on the roof, that houses the antenna. (From what I understand, Bruce is even less impressed with that.)
I look forward to seeing what you've done with the maps. :) I wonder if it'd be possible to have a separate version for tablets and a separate version for PCs?
I agree on the ET3's dial lighting being terrible.
https://www.youtube.com/watch?v=FIYAEn-OPf4
I'm wondering if maybe an e-ink type display might be better for these radios? (But then how do you light it up when it's dark...)
I don't have the Traveler 3 anymore (I returned it), but it did have a little bit of channel change muting or something going on. You do start to hear something right away on a strong signal, but on weak ones it takes a couple seconds for the volume to come up. Also, I think while flipping rapidly through the band, it might "miss" sound sometimes, or something like that, I forget now.
https://www.youtube.com/watch?v=ZUMkHt50Qwo
Also there are some frequencies that I notice some noise on (often coinciding with the signal strength display refreshing), and audio pumping (like 1280 maybe, also sometimes 1030, 910 and 620 even though it's not apparent in the videos). Also, I call it "soft muting" when the volume is reduced as a signal gets weaker. Pretty much almost ALL radios I've ever used have it, it's just that on some of the Tecsuns they have a step-down volume change. On my PL-398bt there was a sequence of keystrokes & things I could use to disable that, but it'd still have some audio pumping.
https://www.youtube.com/watch?v=4SbWavMLxm4 (The video is of my dead PL-398mp. The bt now also has a broken ferrite bar, which has reduced sensitivity about 65-70 dB or so.)
Also in https://www.youtube.com/watch?v=Eqvk51HyIXE - I had the PL-398bt (after the ferrite broke) and PL-606 in my car's back window, and did a drive-by of the KFMB site on highway 52, then turning north on 67 for a short distance. It was done during heavy rush hour traffic, so the first few minutes is slow. If you observe the signal displays, you can see that the PL-606 is changing its desense levels periodically. (When I stopped by the tower, I should have taken the radios and turned them to face the station, but by leaving them in the window the nearest tower which was about 60 or so feet away was nulled.) Then, toward the end of the video, you hear the noise level increasing and the signal getting weaker until it pretty much disappears.
I generally find these DSP radios do couple to at least my Select-A-Tenna though. I generally get about a 20 dB increase in signal strength or so, unless it's being swamped by a nearby strong signal. (And, a strong signal would be one that's over 60-70 dB or so, with above 80 dB especially getting bad, and getting into the territory of desensing the radio such that it reads lower than it otherwise would.)
73, Stephen
HI Stephen,
I always felt my truck radio was pretty hot (sensitive), especially with the 24 inch extension to the whip. I was in the truck on the trip back. That morning, I started out in Flagstaff at 6 AM and drove for 6 hours east on I-40 until I lost KFI just about noon. I was some miles east of Grants, NM, east of the continental divide and within an hour or so of Albuquerque. Of course at 6 AM their signal was full skywave strength as the sun was just coming up in Flagstaff. As the sun rose, it faded through steadily decreasing peaks and nulls till about 10 AM when it entered into this sort of echo-y nether-world where the signal was just barely above the noise, then would fade for longer and longer periods nearing 30 minutes between fades, in and out of the background noise. Audio would be readable for a few minutes, then enter a long fade again. Then it vanished in the noise.
I just got the Honda here in NY so it'll be interesting to check out the receive on the trip back out west. It seems to be slightly less sensitive, but also I've noticed it suffers from more desense here at the house than the truck did. My test station, WWKB-1520 (50 KW) in Buffalo at 60 miles seems to suffer from desense due to the 5 KW WXXI-1370 outlet a mile from here. The truck radio didn't so that. Anyway, that won't matter much on the open highway away from strong signals.
Quartzsite is pretty small, only about 2 miles across, and sparsely populated. Anywhere outside of town is BLM area. Just follow any of the desert tracks off the frontage road on the south side of I-10 (going west toward Blythe), or you can drive a couple of miles north of town and get off into the desert there. It will be hot though. Take lots of water and don't take chances getting stuck. You will die in 115 degree heat without water. You should hear KLPZ-1380, Parker, AZ (35 miles north, 2.5 KW) and KBLU-560, Yuma, AZ (60 miles south, 1 KW) nicely. Phoenix is 120 miles east of you. Look for KFYI-550 and KTAR-620. A good weak signal test for Phoenix is KPHX-1480 (5 KW). Also look for KMIK-1580 (50 KW), Tuscon.
I'm not sure there is any way to optimize the HTML maps for a tablet or phone. There's just too much data. Their little processors just tend to choke. You would have to create maps with less stations. Anyway, I'm done with any more development on the program. 5 years of my life is enough. I'm fixing bugs as I find them, but there aren't many of them left.
73s,
Bill
Hi Stephen,
An e-ink display for a radio would be novel. Nice during the daytime, huh. Need flashlight at night!
Yes, the Eton Traveler 3 muted briefly when tuning between stations. Not sure why they designed that in. That hurdle has been crossed and fixed in digital radios a long time ago. Mine (as others did) also skipped channels often when slow tuning up or down the band, or didn't change the channel at all. The tuning encoder appears to be very cheap. Mechanical, and a cheap one at that, I'm sure.
Soft-mute is that lowering of received signal audio when you tune off channel frequency to make your listening experience "better". Ha! Not good for the DXer! Your pumping audio could be inadequate AGC. Some of these little radios don't have very well designed AGC. Or, your desense might be acting up! :-))
I love it that the Eton Traveler 3 has a full range dBu scale. From 0 to 100+ (127 is possible I think). Great for signal measuring.
Loop coupling just seems to be a little weird in my experience. You can get it to work, but it is touchy to find the sweet spot. It doesn't seem to be that way with my analog radios.
Back to the map plots, unfortunately each plot layer overlays the last and further masks or covers what is underneath even more. That's just a characteristic of Google Maps poly fill function. I'll try lowering the opacity a little. I think it's set at 30 % now.
I'll work on those station lists for you, too.
73s,
Bill
Hi Bill,
I'm finding that another important concern is selectivity and overload rejection. All the sensitivity in the world won't help if a first-adjacent local is stepping on my DX target. For example, where I am, I can't hardly hear 590-KTIE & 610-KAVL (600-KOGO+IBOC), 680-KNBR & 700-KALL (690-XEWW), 750-KOAL & 770-KCBC (760-KFMB), 900-KALI & 920-KPSI (910-KECR), 1120-Mexicali & 1140-KNWQ (1130-KSDO) or 1160-XEQIN & 1180-KERN (1170-KCBQ), just to name some examples. Some other places I've been have even stronger local pests, and I'm not just talking about the times I go to transmitter sites. (My foster grandma is about 1/3 mile southeast of 1300-KAZN and 1430-KMRB, and those render much of the upper band un-DX'able.)
If KFI gets out practically to NM, then maybe I could get KNX in Quartzsite? One thing that's interesting to me, is KNX has a slightly stronger signal than KFI at my house in spite of being 12 miles farther away. It's about a dB or two out in the open, or sometimes in the house it can be several dB or something like that.
Since you're in NY right now, what signal readings do you get on the Traveler III on some AM stations in the daytime, especially the strong local pests and a few DX targets maybe?
I was looking on Google maps, plotting a possible route to go on the DX trip. (I was planning to go today but am bumping it back to tomorrow or Friday cause I haven't slept at all this past night.) My tentative plan is to go east on I-8 from El Cajon, make a stop in Jacumba to check signals there, then stop in El Centro to eat brunch at Golden Corral (I haven't eaten there in a few years, last time was when I was in VA in 2012 I think and it'd been several years before that). I don't expect a lot of DX as there's a few local signals but I may check for a few stations, noise and splatter permitting. Then, on to Quartzsite via CA-78. I'm probably looking at stopping at the Subway / Dairy Queen near Pilot Travel Center and McDonalds, and probably check signals in the parking lot. (Unless you can suggest a better location that's not really far out of town, so if I need to, it'd be just a couple minutes to go to a store & get whatever I might need if necessary. I do plan to take plenty of water anyway.) I'm hoping to be in Quartzsite sometime between noon and 3 pm or so. Then, after that, west on I-10, making a brief stop at the Wiley's Well Rest Area between Blythe and Desert Center, then on west to what may be a Foster's Freeze location near Chiriaco Summit, then southwest around the west side of Salton Sea to Borrego Springs, probably having dinner hopefully around 5 or 6 pm or so at an Italian restaurant on the east side of Borrego (after I check the dial, as it'll be cutting it close for skywave to start coming in), then back home.
My first place to check signals would be Jacumba, and the last would be Borrego Springs, with Quartzsite generally in the middle. If I could try to do it all between, say, 8 am and 5:30 pm, would that reasonably minimize skywave this time of year? (I find that in summer, skywave is less of a factor closer to sunrise/sunset than in winter.)
Ahh, so not much more new things with the program? What's your next plan with it then? Let it waltz off into the sunset? :( or ... would the working out bugs be toward making it available somehow? (I've sometimes thought it'd be interesting to try some things with it myself.)
What you mentioned about the Traveler 3's tuning reminded me of a Radio Shack radio I briefly had. I think it was an analog dial with one of those DSP chips or something. It definitely was "digitally tuned", not smooth analog, and I really didn't like it.
I think a lot of my portable radios seem to be acting up in various ways. :) Many of them refuse to hear stations I'd like to be able to hear. (I have yet to find one that's sensitive and selective enough to get a listenable noise-free and splatter-free signal, with degradation being due to co-channel interference not lack of sensitivity, on every single AM band channel anywhere in North America at noon on the summer solstice during solar maximum.)
I briefly had a Traveler 3, and when I had it about 50-70 or so feet from KFMB's center tower at night, it was reading 99 dBµ so I think that was max. I think it may be possible to get it to read higher for a split second (I've done it with my PL-606 and PL-398bt I believe, but my PL-606 is hard-capped at 63 dBµ), if the signal gets stronger at the moment it refreshes the display or something like that.
Another thing on the map plots ... I remember some of the older ones had spoke lines drawn from the transmitter site to the contour's edge. I think they made it easier to see the contours and see which was for which station, although I don't know that it'd work that well when there's a ton of them layered on top of each other. (For example, what might it look like if you did the 1 µV/m - 1% skywave plots on the graveyard channels...)
73, Stephen
Hi Stephen,
Interesting. I can receive KFI-640 very handily in AZ. It comes in wonderfully on the truck radio, and weakly but readable on the unltralights. Distance is 217 miles. Not sure I remember looking for KNX-1070. I plotted both and even though the output power is the same and they are both monopoles, KNX's signal is vastly weaker than KFI. KNX is only 20 miles farther away, too. It has to be mostly the frequency difference. KFI=0.12 mV/m. KNX=0.03 mV/m.
I did a band scan yesterday morning using the Eton Traveler 3 (530 - 1000 KHz). I'll post the results soon. I'm still impressed with that radio's sensitivity.
Yes, you are right, great sensitivity is useless if the selectivity is so poor that pests override the weak stuff.
I usually allow 2.5 to 3 hours either side of sunrise/sunset to be pretty safe from skywave, especially in the summer. To be really safe, listen between about 11 AM and 3 PM. I have read claims from various technical sources that say winter skywave signal levels at mid-day may at times be only 20 dB less than groundwave. Something to think about!
I still have the ability to draw spoke lines on the plots last I recall. Yes, at times that does make it easier to see what you're looking at.
I'm still doing minor bug tweaks to the program now and then when I see a small adjustment that can be made. That's about it. Not sure about the future. Maybe you'll inherit it at some time. :-))
73s,
Bill
Hi Bill,
When I was in Quartzsite, KFI was easily readable (about 32 dBµ) on the PL-606 with the SAT, but when I removed the SAT it all but vanished into the noise (15/00-02 or something like that). It was also a fair signal on the Superadio III, and fairly good on the Pioneer. Also KNX is weak but readable on the Pioneer, and barely detectable on the Superradio.
When I had the Traveler 3 I did a couple video bandscans in my back yard one day. Here's the one taken inside a small shelter which is now a storage shed but used to be a chicken coop. (It's primarily wood construction with a little chicken wire so it doesn't really attenuate signals.)
https://www.youtube.com/watch?v=ZUMkHt50Qwo
I still need to take my Pioneer out to this place and do a bandscan, and see if it does any better at letting some DX targets through.
https://www.youtube.com/watch?v=XnMRZ2G_3PI
One target that I would hope to be able to hear is 1160 XEQIN. I was able to hear it with a listenable signal at approximately 33.14503, -114.87321 on the Pioneer. (In Quartzsite on the car radio there was some noise covering up its signal, and on the Superradio was at best a ghost.)
I'd really prefer to do my daytime radio tests when there's virtually *no* skywave, at least not detectable without Divine assistance. (For example, a signal above 1600 kHz that would overload a radio on its way up should be undetectable on its way back down.) I don't know how easily that can be achieved, though. :/ There's been days in the summer when I'm monitoring 1670-KHPY around midday, and I hear some fading in its signal which tells me that some skywave is present. And, in winter, on some days pretty much every frequency above around 1300 or 1400 has something on it. On some occasions I've had KMIK overpower KBLA on 1580 at noon, also sometimes KFBK comes in on portables at noon in winter now and then.
Also my bandscan on the car radio in Quartzsite just finished uploading, so here it is.
https://www.youtube.com/watch?v=1uMF7_awQYs
How would you say it compares to what you remember on the truck radio?
Btw I'm thinking that my camera may have put some noise on some frequencies. I had the camera sitting in the rear window, and I believe that's where the antenna is. (I would have used a tripod but as I said previously it broke, and I haven't gotten a new one yet.)
How hard would it be to make an elevation/terrain-style map that shows general contour levels of the strongest station in a given area? Instead of trying to layer each station's coverage map on it individually, it'd show one set of contours for where the strongest signal is maybe 3.16 V/m, another for 1 V/m, 316 mV/m, 100 mV/m, 31.6 mV/m, 10 mV/m, 3.16 mV/m, 1 mV/m, 316 µV/m, 100 µV/m, 31.6 µV/m, 10 µV/m, and below 10 µV/m. (Those are, I think, 10 dB steps.) I picture it looking kind-of like a terrain map, or some other kinds of maps you may have seen overlayed on Google on some sites where there's some color coding / contours going on, or something like that.
I think I've showed you this - https://plus.google.com/photos/118228966367965758611/albums/5484707295038138721/6121203122195899682?authkey=CIer0efojpPg8AE&pid=6121203122195899682&oid=118228966367965758611 - previously, but it's a rough idea of the concept I'm thinking of, except in the pic I just drew random contours, very roughly approximating transmitter sites, signal patterns, etc, but I think I only went up to about 20-100 mV/m or so and kind-of randomly drew contour lines without regard for the actual interval. But hopefully you have a rough idea of the concept I'm thinking of.
73, Stephen
Hi Stephen,
Let me amend my statement slightly about KFI-640 reception in Quartzsite. Not all the ultralights receive it with a readable signal (I'm talking barefoot, with no passive loop). Surprisingly the one which has the best signal is the Sony S10-MK2. As I recall, the little Sony M37V was next, with signal just readable. The SRF-59 was probably third, with very low and hardly readable audio. I'm anxious to get the Eton Traveler 3 out there. I'm sure it will equal the Sony S10-MK2 or even better it. Of course the truck radio was "armchair" copy as they say. I'll also look for KNX.
Your Quartzsite bandscan on the Pioneer was very similar to my truck radio. What's always surprising to me is how weakly 1 KW KBLU-560 in Yuma comes in. Calculated strength indicates a much better signal should be there. It's only 69 miles distant, and over pretty good ground conductivity. There are mountains in between though. And highly mineralized mountains at that. Maybe that makes the difference. KMZQ-670 out of Las Vegas was doing nicely. That is all but unreadable on the ultralights as I recall, unless a loop is used. Their pattern pushes north in the daytime. KPHX-1480 had a readable signal too. Nice. That's a little weak for me usually. KMIK-1580 had a pretty decent signal. Good. The other usual Phoenix and Las Vegas suspects were in there at good strength - KFYI-550, KTAR-620, KDWN-720. KFI-640 was decent too, about the same as mine.
I'll do some more thinking on the terrain style maps you have mentioned. But, I'm not sure how you could merge all the patterns into a gradient. The calculations would be huge. You might be able to calculate strengths based on every few kilometer points (north, south, east, west), but again the calculations would be huge. Google maps requires you to define filled polygons with enclosed latitude-longitude points, so that is what you are calculating.
73s,
Bill
Hi Bill,
I wish I'd had more time in Quartzsite to check my other radios. It probably would have helped if I'd been better prepared with setting up the equipment, if that was possible. Also I had a lot of problems with the camera stopping recording cause I inadvertently pushed on the lens or did something. I need to get a tripod soon, and I'm not sure yet what I'm getting. I've been looking at a few articles and reviews, and some people are recommending tripods upwards of a thousand bucks or more! I can't justify spending that much on one unless my camera body (by itself without the lens) is like $8000+, or I'm making several hundred to a few thousand bucks a day doing photography fulltime. (I'm hoping to find a decent one around $150-250 or so. My last one was about $70 or so and lasted me about 7 years, although it had its shortcomings.)
I think the IBOC hash from 550-KFYI negatively impacted 560-KBLU reception. On the Pioneer you can see it puts the KFYI callsign on the display, but is still too weak to actually switch to HD mode.
Also, I think KBLU is better received in Jacumba, even though it's farther away (about 89 miles). I need to check the video I recorded to be sure, and check whether I even checked that frequency. (In Jacumba I only checked a few frequencies as I had limited time and wanted to allow as much time as possible in Quartzsite.) I wonder also if it's possible KBLU could have been using their night pattern?
I wonder how much a difference winter reception would make compared to summer in Quartzsite....
73, Stephen
Hi Stephen,
Odd, I can't remember ever having IBOC hash problems off of KFYI-550. I see it shows as an IBOC station though. It must be if it showed on your digital display as HD. Maybe I just don't remember the hash. That could be the KBLU problem.
I do remember KBLU being pretty regular on switching from day to night. Their nighttime pattern puts in an extremely poor signal to Quartzsite at night as it's off the back end. I can hear co-channel stations underneath.
Daytime signals seem a little more vibrant in the wintertime in Quartzsite. Conditions are a little quieter too.
73s,
Bill
Bill,
Quick question. I have a need to use the M3_SEQ data that you started with from the FCC, but I can't find any reference to the format of their text file. Do you have any information on that?
Thanks,
David
Hi David,
Yes, I had to figure it out myself, also, as I couldn't find any reference data on it.
A sample line:
9015 29.9100 108.5300 29.6400 108.3600 4.00 2.00
Fields, left to right:
1. Assigned number of line segment.
2. Latitude-longitude of start of segment.
3. Latitude-longitude of end of segment.
4. Immediate ground conductivity east of this segment. (north conductivity for exact east-west lines)
5. Immediate ground conductivity west of this segment. (south conductivity for exact east-west lines)
Hope this helps.
Bill
thanks, that is helpful (if not a bit weird)
Hi Bill,
This map is simply great. I'm working on a project for which I need conductivity by US county and I am completely lost about how to proceed. Do you by any chance have an idea on how I could import this on QGIS?
Thank you very much and again, amazing work!
Caterina
Hi Bill,
Amazing website.
I have the same question as Caterina.
How did you go from the weird data on ground conductivity to the beautiful map in google maps?
Thank you,
Gianluca
Gianluca,
Thanks for your comments.
The ground conductivity map I produced in Google Maps is created by another program of mine called Radio Data MW. It has been in development for about 10 years and produces groundwave and skywave field strength contours on maps directly from the FCC's medium wave database, along with many other data charts. It's some 70,000 lines of code at this point, but not available for distribution. It's tedious to use to say the least!
Bill
Caterina,
I am so sorry I seem to have missed your question.
I don't know how you could import the file into QGIS. A special program would have to be written.
I'm glad you like the map and web blog.
Thanks!
Bill
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